Energy Ltd. News #48
Copyright 2012 Craig Carmichael - February 1st 2012
Month In Brief (Summaries)
Electric Hubcap System - No report
(still no circuit boards for the motor controller!)
Magnetic Impulse Torque Converter Project
* Version 2 tests
* Modified operating principle: magnetic impulse + mechanical hammer
generates short pulses of high torque
* Version 3 construction
Weel Motor - no report
Car Conversion Project - no
report (see Torque Converter project)
* 1100 lumen cold white heatsink drill template; CNC machine
setup/mods/two drills idea
* No word from Energy Star (E-mailing now)
DSSC Solar Cell
Project - Potential
* Found iodine electrolyte to enable DSSC cells.
* Applied as a 'pebbly' skin on cover glass, my nanocrystalline
borosilicate glass mix appears to
offer ~30-45% daily energy performance gain over smooth, flat glass,
* Good gains on cloudy days!
* Commercial panel proves unsuitable for experiments. (Back to DSSC)
Battery Project - No report
* Pourbaix Diagrams: better electrochemical info
* Ni-Mn battery experiments
* Salty cell pH 12.3 with calcium hydroxide
* Alkaline Ni-Mn takes KOH pH from 14 to 13 via permanganate ion.
* Pourbaix diagrams show that pH 12-13 has better chemistries than
either 7 or 14
for ALL the active elements under consideration. (Including it
apparently eliminates zincate ion, making zinc into a long life
* Mn(OH)2 with stibnite charges to Mn metal
in pH 13 alkaline cell - high self discharge, but it may be due
to poor mix with coarse stibnite powder.
* New battery cell constructions to make better cells easier.
* Making new cell with new construction & better mixed stibnite
(but I'm still not confident it's really well mixed).
Construction Manuals and information:
Electric Hubcap Motor - Turquoise Motor
Controller - 36 Volt Electric
- Nanocrystalline glass to enhance Solar
Cell performance - Ersatz 'powder coating' home process for
- Electric Hubcap Motor Kit
- Sodium Sulfate - Lead-Acid battery longevity/renewal
- NiMH Handy Battery Sticks, Dry Cells
- LED Light Fixtures
...all at: http://www.TurquoiseEnergy.com/
(orders: e-mail [email protected])
January in Brief
Solar Cells: big performance gains are possible from any panels
For DSSC solar cell electrolyte, after all this time, I
found a solution of pure iodine and potassium iodide in pure water for
sale at a drug store. The bottle was labelled "Lugol's Solution", a
certainly doesn't betray the contents.
More importantly, in talking on a chat list, reflection
collector glass was mentioned. It seems that about 35% of the total
light energy may be reflected over the course of the day, since much
sunlight and diffuse sky light often strikes the collector at shallow
angles where reflections are as high as total. I then realized that a
great application of the
nanocrystalline titanium oxide glaze I developed would be to sprinkle
it as a frit on the cover glass, and semi-melt it in, to give the glass
a 'pebbly concrete' texture. The little bumpy convex 'lenses'
would reflect much less of the light that strikes at oblique angles,
and the high refractive index of the nano TiO2 would bend it down to
strike the active surface more squarely, making for a good performance
over the day, especially on cloudy days. Daily increase in energy
be as much as 45%, but with only a little more at peak collection times
(sun straight in front) when an increase might overload or overheat the
This would be a good project to get back to,
but I don't know when. [more details: DSSC Solar Cell project report]
Torque Converter: Magnetic and Mechanical
By the third, it looked like the magnetic impulse torque
converter was definitely going to move cars.
Test version 2 showed (virtually by accident) that the mechanical
slack in the mechanism with a consequent twist of the "hammer rotor"
and a hammering of the output shaft
the end stop is reached - can and should play a major part, making very
high torque pulses with just a minimal scale of electromagnetic
components. This led me to a design change with a modified 'theory of
operation'. The revised unit took the rest of the month to make...
still without a cover. Initial tests revealed that the return spring
arrangement didn't work very well, and that a change from rubber to
steel hammers would doubtless be needed. [MTC project report].
Turquoise Batteries - Electrode Compactor Press, CNC Milling
Machine, New Construction Ideas, Manganese Negatrode Tests
For making batteries, I borrowed an antique Book Press
with a "steering wheel" handle to try out - it seemed like it should be
able to exert very heavy pressure. But first I had to make a new
electrode compactor to work with it. This proved tedious work with a
file and I wished I
had a CNC milling machine. Next thing I knew, we were setting a very
one up in my machine shop, borrowed. But just as that was happening,
person came along with an even better plan for an economical CNC
mini milling machine, using a low cost hand milling machine and a kit
turn it into CNC that
could be ordered off the web. It looked like I could be adequately set
up for a little over 1000$. Wow! I'd also like to make injection molds
to make battery cases and other parts, as well as motor and torque
converter parts machining. The first machine will probably go back to
at some point.
I also discovered "Pourbaix diagrams", which give a much
better idea of what to expect from an element at different pH'es. These
suggested that a pH of around 10 to 13 was optimum for all the
electrode substances in question, rather than either neutral salt or
fully pH 14 alkaline. I also found that using salt with calcium
hydroxide gave pH 12.3, and that KOH with a manganese negatrode gave pH
13, as some Mn(OH)3- dissolves, hits the positrode, and goes to KMnO4
and turns the water purple if the pH is above 13.
I also did various experiments with manganese negatrodes
with stibnite to raise the hydrogen overvoltage. I think it's working,
but it's still bubbling, and I suspect the Sb2S3 powder needs to be
ground finer and dispersed better through the electrode at small scale.
In connection with that, I've been considering
modifications to the construction to make the cells easier to make, and
got a new cell half made by month end. [battery project report]
The circuit boards still didn't come. Communications and customer care
don't seem to be on the top of the list of this guy's talents. I
finally e-mailed again on the 29th.
Solutions in Waiting - Internet Shutdown Bills
The more you look, the clearer it is that solutions are
all around us, and are
being kept from us by the greed of the people at the top of the
economic food chain. On the 21st I went into an auto parts store for a
rubber piece. It was quiet and just before closing. I mentioned the
new 'shockwave' rotary turbine (last month's TE News), and this got the
young clerk talking about suppressed engine designs. He soon had names
and videos of several much superior automotive engines on his
computer screen, some of which have been around quite a long time but
aren't in use:
- a "5-stroke" engine with 'water' as one stroke. These are the clean
burning ones getting the great mileage with added water that you may
have heard of. (Without looking into it, I think the heat in the
cylinders turns water into
pressurized steam, helping to drive the pistons with the waste heat of
combustion - that's where the extra "free" energy comes from - it's
energy that usually goes to waste through the cooling system.) I've
heard the engines rust early, but if the designers really wanted fuel
economy, one expects solutions would surely have been found.
- an "exhaust cylinder" engine where the still pressurized exhaust
gasses are decompressed through another cylinder on their way out. He
said this gives double the power of a regular engine.
- a "miller cycle" engine is supposed to be better. We didn't look at
that one (unless it was actually the name of one of the others).
- a "rotor piston" engine where the crank on the bottom of the piston
arm turned a gear running inside a ring gear. I didn't quite follow the
purpose, but it
seemed it eliminated friction.
- an "Atkinson engine". Again we didn't look at it unless it's the name
of one we did look at.
- He said Mazda's rotary engines never had the kind of engineering
went into piston engines - in principle they should be substantially
That people can find and see these sorts of things on the
internet is of course
the real reason the corrupt are trying to have it more or
less shut down. "Know the truth, and the truth shall set you free."
"The truth never suffers from honest examination.: - Jesus. "Freedom of
the Press" so that we may know the truth has long been one of the
hallmarks of a free, democratic
society. Since the mainline press is now controlled by the corrupt,
people are turning increasingly to internet sources to learn what's
going on - it's the new "free press". If it gets shut down, what
happens to our "free countries"? Is our controlled press any better
than the Soviet Union's "Pravda"? Do our votes still count for more
than they did there? Will our democracy be any better,
people more free, than in that benighted state whose demise we all
But people with outdated attitudes die off, and a new
generation of Russian leaders
starting with Gorbachev had a change of heart. We
too will sometime have political and economic leaders that can and will
lead, inspired by love for the brotherhood of mankind instead of fear
and selfish greed. We await them.
A friend says he ordered an electric Mitsubishi i-MiEV
car. It was supposed to arrive in December. Then January. Now February.
And they're changing the terms as time passes. They said he had to get
a 5000$ 240 volt charging station built into his house. He pointed out
that for his driving he doesn't need one, that a regular wall plug-in
is fine. His wall plug-in had to be inspected. Was it inspected? ...Are
these proper demands and questions for people who are just supposed to
be selling a car? (Can you imagine the gas equivalent?: You have to
sign a contract with Shell oil. No? Are you sure other gas stations
have the proper fuel? It might void your warranty if you buy gas at
Texaco. Maybe we'll have the car we promised you last month next month.
Maybe.) He'd better hang onto his
converted electric Sprint until he actually has had the Mitsubishi in
his possession for a few months and is sure there are no strings
Then I heard second-hand that one company was recalling
their electric cars. The person couldn't remember which company.
Obviously, just as in the movie "Who Killed the Electric
Car", they are still trying to delay and frustrate as long as possible
and to get people so annoyed that they decide they won't deal with them
and hence don't buy an electric car. Then they'll turn around and say
the public doesn't want electric cars. (I considered that line in the
movie to be the most outrageous piece of lying
effrontery I had heard since the collapse of the Soviet Union.) I'm
sure it's the same everywhere. If anybody has had a simple,
straightforward time purchasing a new factory made electric car, please
let me know and prove me wrong.
I received a
disquieting phone call
on January 26th (from "Blainco Enrgy V", a 403 Alberta phone number per
my phone display) asking me to verify Turquoise Energy's address and
phone number. When I asked, it was "on behalf of oil companies in
Calgary". It may mean
nothing. But why should they be so interested in other companies
affairs? - I've never had such a call from, say, a wind power company,
or anyone else, and I can't imagine making such enquiries myself.
It's obvious that "big oil" reaches far to eliminate
alternatives to "big oil". I try to stay off their radar
screen, but I must put my work out there if others are to make use of
I visited an ex employer earlier in the month, the retired Facilities
Greater Victoria School Board. He said I
should switch to doing scooters or wheelchairs or something
instead of cars, "or you might come home one day and find your house
burned down." Best not to dwell long on such morbid thoughts.
Magnetic Impulse Torque Converter Project
Experimental Version 2: Copper wedge on motor rotor,
and 'wedge' of 5 supermagnets on output "rotor".
Version 2 was just a bench test version. Per photo, the copper wedge
was on the motor rotor and 5 supermagnets making 4 magnetic polarity
reversals were screwed to a piece of black locust wood on the output
shaft assembly. A torque wrench
on the output shaft measured the
Even at very low motor RPM, this made around 10
foot-pounds of torque whenever the copper and magnets crossed. The
motor slowed visibly or even stopped. It picked up speed over the other
4/5ths of its rotation. Of course, the faster the motor turned, the
more frequent the torque pulses were, and the more acceleration there'd
be. As per previous findings, the strength of the torque pulses didn't
increase with speed beyond a certain low RPM point; I'm not sure they
hit 15 foot-pounds. The motor rotor was very unbalanced with the heavy
copper on one side, so no test went above about 200 RPM.
Some play in the torque wrench attachment lead to the
discovery that if the magnets could pick up a bit of the motor's
rotational speed and then suddenly be stopped at the end of the play,
the force, tho shorter duration, was doubled and more: readings shot to
over 20 foot-pounds even with just a couple of degrees of free play
helping each rotation. With the 4 to 1 chain reduction following,
80 foot-pounds at the wheels should definitely have nudged the Sprint
into motion on level ground - all with a motor just turning over and
using under 150 watts.
This led to a modified design incorporating free play
rotation, more akin to the first plan in December. The magnetic
coupling could be reduced somewhat rather than substantially increased.
For version 3, four magnets on the [1/4" steel] motor rotor would
with a [1/4" thick] copper wedge on the [aluminum] hammer rotor.
The lighter hammer rotor would start to spin, accelerating towards the
motor speed for about 45º, then hit the end stop, hammering the
output assembly with a sudden hit of high torque. In the 4/5 free time,
the motor would speed up again as before, and the hammer rotor would
spring back to its center. In this design I hoped for 50 or more
foot-pounds, to give the wheels 150 or more with a 3 to 1 chain drive.
Even more might well be attained, in which case some rubber or springy
steel might be added somewhere to spread the torque pulse out over more
time with less of a sharp peak. Another idea is to put two supermagnets
at each end of the travel to repel each other as they closely approach,
eliminating any physical hit. This could also eliminate the need for a
For this new working version, different parts and layout
were required, so most of the unit had to be rebuilt, which took until
the end of the month. First tests on the 31st and February 1st showed
the unit to be stiff, and the torque low. Evidently the motor got one
too many spacers inside, putting pressure against the bearings, the
return springs didn't bring the rotor back near center, and the rubber
hammers should be replaced by steel ones. February awaits.
Version 2 Tests
On Jan. 2nd I made a wooden block "wedge" to hold 5 magnets to
"complete" (just for test purposes) the second version converter.
Next day I got it mounted and tried it out on the bench.
The counterweight on the motor rotor attracted the magnets so strongly,
in spite of the additional 3/16" gap, that the wedge managed to pull
over sideways and
clamp onto it. I finally took the counterweight off so that I could
run tests at all.
I tried it with three magnets, and got readings of perhaps
7 or 8 foot-pounds of torque at about 120 RPM. Each time the motor spun
to the engaged position, it lost most of its speed. Testing was tricky
- if the off-balance motor got up to about 200 RPM, the whole bench
(okay, it's not Victoria's most solid, heavy workbench) began to shake
so violently I couldn't read the torque wrench.
Then I put on all five magnets. This tended to bring the
motor to a complete stop (great low speed force coupling!), and I had
to increase it from 12 to 18 volts. I got readings somewhere around 10
foot-pounds. That would be 40 at the wheels, 'move car on level ground'
torque. That was within the target range, but somewhat low. It seemed
that even magnets with copper wedges on both faces might still be
underpowered for decent vehicle performance, and that two rows of
magnets and three of copper wedges would be needed.
The motor was only using about 7-8 amps at very low RPM
and quite a low 'throttle' setting, hence using only a little
electricity. 8 A * 18 V = 144 watts, 1/5 of a horsepower input. That
would be to get moving on level pavement - power needed would increase
with RPM, ie, as the car gained speed. Still, it seems to show the
ultra-efficiency I've been after.
The motor could be seen speeding up and then rapidly slowing down with
Then a strange thing happened. When I got the torque
wrench handle just right, right angled from the unit, it seemed to be
really getting hammered, and the torque readings went as high as about
25 foot-pounds. At any speed where the motor didn't stall, the reading
was over 15 foot-pounds. 25 would mean 100 at the wheels, well up
towards putting the Sprint on the street.
Part of my original plan was for a mechanical springyness
to assist the magnetism. The output arm would start to turn freely with
the input as it flew past, then hit a slightly springy 'end stop' which
would transfer both the electromagnetic pull and the kinetic energy of
the moving weight suddenly to the output shaft. I had to bend the
slightly springy arms around to fit the wooden magnet wedge holder on,
and now they wouldn't have much spring to them.
I had also made the hex shape on the shaft to fit the 22mm
wrench socket quite closely. However, the factory made 1/2" square
wrench end and the hole for it in the socket weren't such a good fit,
and if they were square on, the arm could pivot freely about 1/2 inch
before it hit the 'end stop' of the slack in the wrench connection.
Thus the torque wrench itself was providing the slack needed to gain
the mechanical assistance, and evidently about doubling the peak
torque. If I held the arm so it didn't bounce back after each hit, the
torque dropped back to the lower levels. The torque wrench was designed
for steady readings - the needle bounced wildly with the pulses. I'm
understating the actual readings hoping the figures are more in line
with the actual case, but there's a lot of room for error.
Of course without
the "assist", the
output "gradually" rose to 10 foot-pounds and fell again over the
time the magnets and copper were crossing each other, while the 25
lasted only "an instant". The motor was drawing only 7 or 8 amps either
Now if the slack
were increased to maybe 3 or 4 inches, the arm would have more time to
pick up the motor's speed, and the effect should be still greater -
again, or even more. With this mechanical hammer assist built into the
output rotor mechanism, the 6 inch wedge of copper with 3 or 4
supermagnets (plus a 3 or 4 to one chain or gear reduction to the
wheels) really seemed it should have enough force to put a car on the
street. I reduced it to 3 magnets and still got up to 20 foot-pounds or
so. I decided to go with 4. It seemed that a fair
gap, eg 1/10" or more, would work fine - no need to get it to
an inch with the precision that would call for.
Another way to give the mechanism more slack - on the car
but not on the bench as set up - would be to loosen the chain to the
differential. It would be suddenly jerked tight every revolution as the
output rotor started to turn. Without a spring there'd be nothing to
actively push it back to "start" position again, but it bounced back
and forth in the first test at propitious RPMs, as it did with the
torque wrench on the bench. Notwithstanding the several deficiencies
of the construction, I decided to try it out on the car.
But the next morning it was pouring rain. Perhaps instead
it was time to make that lexan cover to enclose the unit to keep road
dust and water out, and so that if anything flew off, it wouldn't hit
me, or later, end up lying on the road somewhere. I really like the
transparent cover idea, since everyone will want to see how it works
once the car is running, and lexan, while it looks the same as
plexiglass, is supposed to be able to take rocks thrown at it without
getting more than scratched.
I went out and bought the plastic, but got no further, and
I didn't try the unit on the car. The wet soon turned to bitter cold
(for Victoria... -6ºc) and snow for a week, so I took the unit
apart and picked away now and then at making version 3 in the chilly
Gluing PP strapping onto magnets
Pieces of the torque converter: 'anvil' arm on output rotor, copper
block side of hammer rotor,
input rotor (before refinishing)
"Finished" V3 converter. Left to right:
- magnet rotor on motor shaft with wedge of 4 supermagnets
- hammer rotor with copper wedge, hammer assembly with rubber cylinder
'hammers', springs to output shaft assembly
- output shaft assembly with anvil arm, the other end of the springs
- chain drive to differential, then bearing hub for output shaft
A question was how heavy to
make the hammer rotor. It should be lighter so it doesn't
slow the motor rotor down as much as it itself speeds up. Banging the
output arm with a one pound
hammer made 20-30 foot-pounds of torque, and a 2 pounder made 40-60.
(Naturally it varied with the swing, and I don't really know how that
compares with motor speed. Also the needle arm of the torque wrench
bounces so much it's hard to decide what it really reads.) The latter
was the desired force range, but
the rotor was bound to be over 2 pounds, so I decided the lighter the
better. So the rotor is 416 grams of 1/8" aluminum and a
1/4" thick copper block weighing 407 grams replaces the original 1/2"
piece. The copper will of course have to be counterbalanced, making
over 1200 grams already. Since epoxy doesn't stick to aluminum, the
copper and other attachments will be bolted on. I decided to go for
rubber 'hammers' to hit the 'anvil' arm with.
I'm concerned the 416 gram 1/8" aluminum rotor may bend
under the forces. If it does I could add some steel bracing, or I have
a 3/16" piece of aluminum to try, but weight would
1. The wedge of  magnets goes back on the 10" diameter 1/4" steel
motor rotor. Counterweight opposite the magnets.
2. A 1/8" x 10" round aluminum hammer rotor.
3. The hammer rotor turns on a single bearing on the motor shaft.
Putting it on the motor shaft keeps it aligned with the motor rotor.
Alignment of the hammers with the anvil arm doesn't need to be very
4. The copper wedge (facing
and a counterweight/hammer assembly (other side) are mounted on the
hammer rotor. Near the
edge on the outside the forward and reverse 'end stops' are two rubber
"hammer" blocks, and there's a light spring assembly to
return the hammer to center.
5. The output shaft assembly has
a stiff 10" steel "anvil" arm matching the rotor diameters. The rubber
block strikes one end of this arm to turn it forward, and the other end
Note that everything now mounts on the motor except the
'anvil arm' on the output shaft.
On the 21st I talked with a brother (a biochemist) by
phone and described the torque converter. He didn't like having pieces
that hit each other that would make noise and would wear out. He
suggested having two supermagnets with like poles facing each other,
that would repel each other more and more strongly as they approached,
and presumably would never quite touch. This would probably also
eliminate the need for the return spring, since the rotor would center
between the forward and reverse pairs of magnets. Two concerns are:
(a) that the magnets might hit each other if the torque forces are too
strong and the magnets not strong enough. That can be addressed with
sufficiently large and powerful magnets.
(b) that the magnetic cushioning effect will spread the stopping force
over too gradual a time and distance, making the torque pulse longer
but too weak. To address that, one could use thinner magnets with less
depth of field... but that's likely to cause problem (a).
But if the concerns prohibit a totally magnetic solution,
perhaps one could put in enough magnetic repulsion to handle weaker
forces, but still have the rubber end stops for when loading is high.
And the magnets could still replace the return spring. I like the sound
of using purely or at least partly magnetic 'hammers'.
I had just completed the hammer rotor unit with rubber
'hammer' pieces when we talked, but assuming that works okay, I'll
certainly try out the repelling magnets idea later. (Then it'd be a
'magnetic impulse' torque converter in two ways, instead of 'magnetic
How Much Torque?
I've been guessing that 130 to 160 foot-pounds of torque
would be sufficient for the Sprint. I watched a video about the
Mitsubishi i-MiEV and evidently it has 180 newton-meters - that's 132
foot-pounds - making it "pretty quick and powerful", the fast starts
impressing drivers. And it was
doubtless heavier than the Sprint - it had enough batteries for a 90
Sounds like 100 foot-pounds might make it quite driveable.
If I can get 40-45 from the converter and reduce it 3 to 1 with the
chain drive, that's 120-135. That sounds doable. 2.5 to 1 or 100-112
foot-pounds would improve top speed from under 60 to about 70 KPH.
(With the 4 to 1 reduction I'm using for testing, it'll be under 50
KPH. But it gives 100 foot-pounds at the wheels with only 25 from the
Of course, intermittent pulses of torque aren't going to
give the same acceleration as continuous torque. It's still "try it and
see" in many respects - the final effect isn't readily seen in advance
of experiencing it.
Magnetic Impulse Torque Converter Theory (Modified)
1. The motor has a 10" diameter rotor on on its shaft, the input shaft
to the converter. This rotor
and the motor's internal magnet rotor act as a flywheel to store up
kinetic energy as the motor rotates.
2. The rotor has four supermagnets arranged in a wedge shape on the
side facing out, N-S-N-S, to
rapid transitions from null to north to
south to north to south to null as the magnets spin past a given point.
3. A hammer rotor is mounted on a bearing on the motor shaft. It can
thus turn independent of that shaft, but only for a small angle
relative to the output shaft, about
30-45º either direction, then its hammer hits an end stop on the
output shaft. When there's no
force acting on it, it returns to center between the end stops on the
output shaft via a
4. This hammer rotor has a 6"
long (O.D.) by 2" wide by .25" thick wedge of
copper, oriented so that its flat
face almost touches
the flat face of the supermagnet wedge as it spins past, with a small
5. This is the magnetic impulse part: As the 6" copper wedge spins past
especially at their sharp north-south magnetic transitions, the magnets
electricity into it. The electrons looping though the fat copper
short circuit create an equal and opposite magnetic field*, which
resists the motion of the magnets across the block. The hammer rotor
with the copper wedge is strongly pulled and starts to speed up towards
the motor speed. At the same time the motor is being slowed by the same
force, but the hammer rotor is lighter. Before the magnets reach the
end of the copper, the two rotors
are traveling at almost the same speed.
6. This is the mechanical hammer part: The hammer rotor, now going at
the same RPM as the motor, slams into the end stop. For an instant, a
very high torque is generated, similar to a hammer hitting a nail, and
the output shaft is given a twist; driven around.
7. If the load is heavy, the output may move a fraction and stop.
Facing uphill with a low motor speed, it may even turn back again. If
the load is light, or else as the motor speed increases, the output
shaft won't stop turning between hits and will accelerate with each hit.
8. As the motor magnets pass the end of the copper wedge, the output is
'disconnected' from the input: no force or motion is transferred. For
the other 4/5ths of
rotation, the motor spins freely and picks up its lost speed, until
magnets and copper wedge cross each other again.
9. As the output accelerates, the motor
will likewise pick up speed. When providing torque, it will always be
going a little faster than the output, by perhaps 50 to 400 RPM,
depending on the torque required. This provides a variable transmission
ratio based on speed and torque.
10. If, as seems likely, the torque converter output torque isn't high
enough by itself to properly propel a vehicle, the output shaft feeds a
fixed ratio reducing gear to divide the speed and multiply the torque
instead of turning the car wheel or drive shafts directly.
* Callisto, a world the size of Mercury,
has a weak and fluctuating
magnetic field induced the same way - by Jupiter's strong field,
its conductive salty water mantle. Callisto also gets speeded up
(so slightly) in its orbit as "the motor", Jupiter, and its magnetic
field, rotates every 10 hours, much faster than Callisto's 16 Earth day
orbital speed. According to scientists, airless Callisto (in common
with Ganymede and the leading hemisphere of Iapetus) has a dark, fluffy
surface of polycyclic aromatic hydrocarbons - the stuff of life.
LED Lighting Project
On the 4th, seeing what might be good
markets, I decided I should get going on a system to produce LED
light fixtures more rapidly. I made a drill template for the 1100 lumen
"cold white" (slightly bluish light) fixtures, and the next day I
bought a piece and made an attachment to hold the plastic bases (3" PVC
plumbing pipe caps) on a stepper motor from the CNC drill router.
With that, many small vent holes, the globe attachment
holes, and the power socket hole can be drilled with good, even
placement. Of course, the holes will all have to be drilled the same
size, and the power adapter hole will be drilled out to full size
I had the machine make the first set of vent holes -
worked nicely - and put
together a new 1100 lumen cold white globe fixture with that base and
the new heatsink drill template, but I was more excited by battery
chemistry and torque converter developments, so there things sat for
the rest of the month except for a couple of LED fixture parts
A CNC Machine Improvement?
It would be good to make the vent holes bigger than the
globe attachment holes, and indeed on more than one part it would be
valuable to have at least two different size drill bits. To stop and
change bits is a hassle, and has to be done by swapping two CNC drill
programs back and forth, with much delay and all the dangers of
something going wrong and things getting misaligned. I was starting to
think that a way to change tools or drill bits within a CNC program
would be valuable, but it seemed it would be very complex. Then I got
the idea to mount two drills side by side, farther apart than the size
of the workpiece, eg, 12" would do for these and for up to, eg, 12"
motor parts as well. They would both run, and when the other drill size
was wanted, the drill position would simply be shifted 12" to place the
other drill over the work.
It would take some setup work and a couple of new, matching, drills -
but it would be
a big help.
Those holes are around the rim. The holes in the back
still need to be done first, by hand with a template. The 'keyhole'
holes for hanging the fixture on a wall
increase the requirement from 4 to 6 holes (two large ones for the fat
part of the keyholes) and filing down from the small hole in the
keyhole to the large one.
It's worth it - in no other way is it possible to install a light
fixture simply by hanging it up, without even opening it. The days of
immobile wired-in light fixtures may be numbered!
I must next consider whether a switch might not be a good
option for lights on the wall that are easy to reach. And if a switch
is going to be added, whether that might not b a 3 position switch:
I've heard nothing from Energy Star. At the moment I'm
assuming Turquoise Energy has been registered in the program. On the
31st I e-mailed and asked how to submit the lights for testing.
DSSC Solar Cell Project - Potential Revival
Two things happened to renew my interest in this project.
The first was finding the electrolyte for DSSC cells, I2+KI
in pure H2O, in a
bottle at a drug store. It was labelled "Lugol's Solution", which name
disguised it quite effectively from anyone looking for iodine.
Second and more importantly, there was an e-mail list
a 3-D solar collector, which could capture more solar energy from
a given surface area. One of the claims really surprised me: that
since the collector cover glass reflected about 35% of the light, light
reflecting off one panel could feed others within the 3-D structure.
This uncovered a significant potential value of the nanocrystalline
titanium dioxide borosilicate glaze mix I created in summer 2010.
At first I thought they must be exaggerating to make the
3-D system sound better. I'd guess that when the light is beating
straight down on the collector, there's surely much less reflection
than that. However, as the angle of
incidence decreases, eg, in earlier morning and later afternoon, the
glass would indeed have very high reflection if not total internal
reflection, so it might very
well be that 35% of the total light is reflected away from the cells
course of a day, and hence 35% of the potential energy is wasted. And
much of the diffuse light coming from all over the sky, including on
cloudy days, must also go to waste.
Furthermore, most of this loss would occur when there's
less light energy per unit area, at which times the cells wouldn't be
overloaded or overheated by getting more light. So the effect of lower
reflection would be to increase the average daily output, potentially
up to 35%, without adding a lot to the peak collection when the cells
might potentially overheat.
With this background, it can be seen as very significant
that nanocrystalline surfaces with nano-scale surface
irregularities, reflect less light than flat surfaces. Moths'
nanocrystalline eyes are virtually
non-reflective, unlike almost any other creature's.
But why not expand on this? Why have flat glass at all? A
good plan might be to
grind the "glaze mix 9" (TE News #29) nanocrystalline titanium dioxide
borosilicate glass into a
frit, sprinkle it on a piece of
regular window, greenhouse, or borosilicate glass, and heat it until it
spreads but only partly melts in,
leaving a pebbly surface texture of 'random' little convex lenses to
collect oblique light and transmit it through. Perhaps the dust could
be suspended in water
and sprayed on the main glass with an atomizer.
Much oblique light would hit a convex glass
surface facing it, at a steeper angle than flat glass, again reducing
reflections. The high
refractive index of titanium dioxide would help the 'lenses' bend the
a straighter course through the glass, to strike the collecting surface
more steeply. This might especially benefit polycrystalline or
amorphous silicon panels. Thus more of the 35% would be transmitted
instead of reflected, boosting the energy collection of the same panel.
If 25% of the normally reflected 35% was
transmitted to the cells,
they'd receive 90% of the day's light instead of 65%... a 38%
On cloudy days when light
is diffuse and
striking the collector from "everywhere", low and high angles, the gain
should be considerable, catching the most of the scant available energy.
nano TiO2 glaze surface is the important part. Only a
glaze on existing glass is needed - much simpler than making whole
sheets from scratch!
Trying a commercial solar PV panel
My first thought was to simply buy a small panel, remove
the cover glass, and work with that. I bought one at Canadian Tire for
17$. Sure enough, with the unit held at oblique angles, the collector
surface was dimly seen or not visible - mainly external reflections
be seen in the glass.
But when I disassembled it, I found that the cells were
some sort of film on the back of the glass, not separate items as I had
expected. Obviously the solar cells would be destroyed by the heat of
Then I was told that was the case for amorphous
silicon, but not for polycrystalline or monocrystalline. It
that I might either find the right type of silicon cells, or make DSSC
cells. But I might not find a silicon panel that could be separated
the glass small enough for the mini-kiln. At a solar collector store
that proved to be the case.
The glass of the one I bought seemed to be cheap greenish
"window glass", not
a good borosilicate ("pyrex") glass for maximum transparency. (What did
expect for 17$?) "35% reflections" seems more and more likely to be a
pretty good estimate.
Evidently the first step, then, will be to grind some frit
and try making a piece of pebbly surface glass. Then I'll probably need
to make a DSSC solar cell to test it with.
Turquoise Battery Project
I found and borrowed a "book press" and made a new
electrode compactor to work in it. I crushed some of the
quartz/stibnite rock with a hammer and made a manganese negatrode with
stibnite additive in it to increase hydrogen overvoltage. The stibnite
is likely to form keresemite (Sb2S2O), "the least oxidized" such
compound of antimony, in the reducing electrode.
I made a cell. The monel positive electrode could be seen
to convert to blue-green nickel and copper oxides/hydroxides and to
swell into every possible niche inside the cell. The conductivity
became poor. I came up with the idea of wetting the positrodes while
they were held compressed and leaving them a day or two, to keep them
from swelling before they hardened up some.
I discovered "Pourbaix diagrams" that plot compounds
formed by a metal that predominate at different voltage potentials and
pH'es of solution. This added both insight and complication. For
example, it appeared that at neutral pH, the Mn(OH)2, or perhaps some
unspecified amount of it, would dissolve as Mn++ ion. This suggested
that a somewhat - but not strongly - alkaline solution would be best.
But then, a nickel Pourbaix diagram showed that nickel should dissolve
to Ni(OH)3- ion at pH 14, which it clearly doesn't do to a notable
extent in all those
Ni-Xx alkaline batteries. (But then, maybe that's why they don't have
unlimited, indefinite cycle life?)
I discovered that my salty electrolyte was in fact rather
alkaline, evidently 12.3 from the calcium hydroxide layer in the
At least the grafpoxy seemed to be working - the cell
work without the meager specs degrading or the electrode grills falling
The next cell is to incorporate these findings and
techniques. It is for considerartion whether to use the Ca(OH)2 and
have a "somewhat alkaline" cell, or leave it out and try a neutral pH.
The "somewhat alkaline" is more likely to have the desired hydroxide
whereas the really neutral cell may discharge the negative to chloride
rather than hydroxide, which would be a dissolved ion form as
indicated in the Pourbaix diagram.
Then I decided to make a Mn alkaline cell pocket negatrode
with the remaining MnO2/graphite/1% stibnite mix, and put it in with
the nickel positrodes from a nickel-iron cell. Would the Mn in
alkali (a) dissolve, (b) bubble hydrogen, or (c) charge and work?
I put it in a perforated brass screen pocket - pretty coarse compared
to the original pockets - wrapped it in zircon coated watercolor paper,
and put it between 2 of the original NiOOH pockets in the NiFe cell
case. This one was pretty well enclosed on all sides. It seemed to be
part of (b) and (c). In some ways, the performance was excellent, but
it didn't charge well or hold the charge very long. I eventually
decided the stibnite probably wasn't very finely dispersed, so not all
of the electrode substance was getting its overvoltage raised. Possibly
also the brass metal was a problem. On the
26th my new stibnite powder arrived.
This month I also posted an unfinished preliminary version
to Make Economical, Green, High Energy Batteries" in response to
e-mail queries. It would be better to wait until I have working cells,
but after 4 years I felt I had learned enough to put it down in case I
got run over where the city refuses to put in a crosswalk for us where
it's most needed.
New Compactor & Book Press
I went to a new years eve party/music jam. I noticed the hostess had a
couple of heavy looking presses in the hallway with big "steering
wheel" cranks to tighten them. I wondered if they might be suitable for
electrode compacting, instead of doing up 14 small bolts around the
edges of the compactor box.
She said they were called book presses, and I
borrowed one to
try out. Then I realized it would be tricky to use the existing
compactor box - it depended on the side bolts to hold the side walls on
during compaction, and the bolts would be in the way in the press.
So I spent several hours making a new compactor box with 3/4" thick
walls around the box, all one piece. After hacking out the 1.5" x 3"
electrode size a bit undersize with the angle grinder/zip disk and
drills in the corners, most of the time was spent filing out the hole
to smooth, exact size with files.
I couldn't help but think the compactor would have been
far easier with
a CNC milling machine, and it would have done a better job - a couple
of zip disk cuts still showed in the finished piece where it had cut a
touch too far, and the angles weren't exactly 90 degrees.
I've been vaguely thinking a CNC milling machine would be
a great thing to have to create precision steel parts. In particular,
electrode compactors, and injection molds for battery cases & lids
and for filler caps/one-way vents might be helpful. I know a place that
does plastic injection molding - perhaps I'd make the molds to create
my shapes and suit their machine requirements.
It can have uses for other things as well, eg, cutting key
slots in motor shafts, cutting out copper wedges and perhaps other
parts for torque converters, but salable merchandise for the battery
project was my main thought.
The short story is: I got one for a little over 1000$.
Unless you just like stories, or want to know how to get a low cost CNC
milling machine, I suggest skipping from here down to the next heading.
On the 7th I went to a group brunch at a restaurant, and
came home at 4:30 with a CNC milling machine. My friend who had sold me
the CNC drill & wood/plastic router, had purchased the milling
machine just prior to that, but hadn't even set it up in a year and a
half. He suggested we set it up at my place, and so we spent the
afternoon packing, transporting, and assembling it. I figured having
someone else's machine in my shop couldn't be a lasting arrangement,
and considered mortgaging my house to buy it from him and have money
for the rest of the year (and for LED light fixture parts if I got a
But as we set it up, another friend happened along. He
mentioned that the new Princess Auto store had a mini milling machine,
with hand cranks, for 600$. Then you order a kit off the internet for
another 600$ that turns it into a mini CNC milling machine.
I went out there and looked, and the machines were on sale
just 420$, complete with beefy looking precision drill chuck and a
heavy collet chuck with 8 collets - surely a couple of hundred bucks
to buy separately, and the big machine didn't have them. I bought it.
It's much smaller and lighter, with a
more limited work size (4" x 8" instead of 8" x 8"), but it seems
decent and is probably sufficient for
my milling needs. There appeared to be about three different kits
available to turn it into a CNC machine, and the one that sounded best
to me was also cheapest at 465$ [StirlingSteele.com].
These kits are just the mechanical parts and don't include
stepper motors or computer interfaces. I can probably buy a couple of
used stepper motors, and as long as I only use the milling machine
occasionally, I might just unplug the stepper motor cables from
the drill-router and plug them into the milling machine, and hence use
the same computer and setup for both. That technique worked well for
the LED light fixture vent hole driller, where I unplugged one axis and
plugged it into another motor that rotated the fixture base.
Amazingly then, it seems I'll soon be set up to mill steel
for not much over 1000$. If the second friend hadn't payed me a rare
visit right while we happened to be in the middle of setting up the big
machine, after the impulse decision to do so that morning at brunch,
the subject would never have come up and I'd never have heard of the
mini-mill and CNC conversion kits. Kudos to the angels for managing to
set up this remarkable convergence!
Manganese Negatrode (take 3)
A Pourbaix Diagram for Manganese suggests that pH 8
to 13 would
usually considered to
have the highest usable
negatrode voltage, -1.05 volts in salt solution. Manganese is perhaps
the next voltage up of
the usable elements. I was
guessing that its potential in salt was
the average of acid and alkali, -1.37 volts. I knew that was risky but
had nothing else to go on.
be good for a battery using it, as it has no dissolved forms
anywhere below around a volt at those pHes.
Recently I found (for the first time) something called a Pourbaix
diagram (first ones were by Pourbaix, 1966), showing the
predominant forms a substance is most likely
to take at different pHs as well as at different voltage levels, and I
found one for manganese.
As can be seen, the potential for the Mn (0) to Mn (+2)
reaction is about -1.18 volts from acid to neutral pH. That's only
about -.13 volts higher than zinc at pH 7.
Nevertheless, in previous attempts, my Mn electrodes have
bubbled hydrogen and wouldn't stay charged very long.
Furthermore - and this was unexpected and disconcerting -
at neutral pH (7), the discharged state of the Mn appears more likely
to be a
dissolved ion (MnCl2?) than solid Mn(OH)2. This suggests that cells
Mn negatrodes should be somewhat alkaline, at least pH 8 but not beyond
Here we also see
perhaps why no one has used Mn negatrodes for alkaline cells, even if
the -1.56 volts permits: it would seem it forms a soluble ion, Mn(OH)3-,
at such high pH (14).
The page that I got the Mn Pourbaix diagram from,
Diagrams That Provide Useful Oxidation-Reduction Information; www.wou.edu/las/physci/ch462/redox.htm
, had other diagrams I hadn't seen before
and seemed to be a fine treatise on the whole subject.
Pourbaix diagrams seem to have limitations. Those from
different sources don't all seem to agree with each other or with some
known battery reactions. One set of Mn ones suggests the pH should be
at least 11 or 12, that 8 to 10.5 would be Mn++ instead of Mn(OH)2, a
considerable discrepancy. It's probably not that one or more is wrong,
but for example the condition of the those diagrams was "very low
concentration" of the element in question, as pertaining to its
transport through the water table - hardly the conditions in a battery.
It may be that only a bit will dissolve as Mn++ even at pH 7 owing to
limited solubility, and then the rest will be solid Mn(OH)2 in the
electrode. And many of the diagrams only go to about ±1 volt,
even just -.8, which leaves out the most interesting battery reactions
of charging to elemental iron, zinc, cadmium, and even hydride. For
high energy batteries we're most interested in about 1.0 to 1.5 volt
Hydrogen voltage at pH 14 is -.833, the voltage of metal
hydride cells. Various electrode substances prevent it from forming
until a higher voltage is reached. Zinc (-1.05V in salt, -1.24
alkaline) works as-is, but its
performance can be enhanced by
raise the hydrogen generation voltage. Iron (-.93V in alkaline) has a
lower hydrogen overvoltage. It works but tends to bubble hydrogen. Work
in India in 2004 used 1% bismuth sulfide to raise the overvoltage, and
a platinum-rare earth catalyst to recombine O2 and H2 into H2O,
permitting sealed NiFe dry cells for the first time. Manganese (~-1.56
@ pH 14) won't
The electrode bubbles hydrogen instead.
A year ago and more,
manganese could make a higher-energy negatrode, provided the
electrode's hydrogen overvoltage could be increased by whatever small
was needed to charge Mn(OH)2 to Mn
metal particles instead of generating hydrogen.
Others have used
transition metals - tin, mercury, bismuth, gallium and indium - or
their oxides to
raise hydrogen overvoltage for zinc. "Traditionally" (before the
1970s), about 2.5-4% mercury oxide was used. When the other transition
metals mentioned were tried (probably because of the toxicity
of mercury), it was found that only .05-.5% had to be added to get the
From reading other results, I thought that cheap antimony
- to the right of tin and above bismuth on the periodic table - tho
untried by others, would probably work best. First I
tried antimony oxide. That didn't quite seem to do the trick.
On looking at the web, I found a 1962 research article
abstract that indicated egg albumin (main ingredient of eggwhite)
should raise it, seemingly more than enough.
Unfortunately both additives left the manganese with too
high a self-discharge rate to be practical. I planned to try antimony
sulfide, but finally quit trying without getting hold of any.
I'm finally trying it. I got hold of a quartz rock with
"stibnite" (antimony sulfide mineral) in it as a source. I broke off a
piece and put it in water, and some yellow-bronzy colored stuff
appeared. At first I thought it was sulfide turning to oxide, then I
decided it was most likely some other 5A element "impurity" - a
phosphorus or arsenic compound. I scrubbed it with a toothbrush and got
some of it off.
I only want maybe 1% antimony sulfide in the electrode,
and the quartz should be pretty inert. But things that leech out of a
rock in water probably aren't the best inside a battery!
The stibnite (Sb2S3) may form
"the least oxidized" derivative, in the reducing negatrode environment.
Both forms are virtually insoluble.
With the rock in my possession, I then magically ran
across a US company [americanpyrosupply.com] that sells antimony
trichloride for pyrotechnics (12 $/#) and ships to Canada (and
via the post office). I ordered
a couple of pounds, which arrived before month's end.
I considered that if I used the Mn metal powder, it would
be likely to have particles that were too large (even tho it was
<320 mesh sieved), and wouldn't get adequately mixed with the Sb2S3,
and so the electrode would again have high self-discharge as well as
low amp-hours for the amount of manganese. (In fact,
maybe that was the problem, or part of it, before.) The 1969 book Alkaline
Storage Batteries noted that in all cases, zinc electrodes from
zinc oxide worked better than those made from zinc metal powder. And
the zinc powder was surely finer than my manganese powder.
If I used MnO2, it would be likely to shrink and
'de-compact' itself as it lost oxygen atoms. And if I used MnO2 from a
dry cell, it would probably have more graphite than was good or useful.
MnO2 from the pottery supply might not be very pure.
I decided to put some of the metal Mn powder into water
and let it discharge itself to [presumably nanoparticles of] Mn(OH)2
(or MnO), and then dry it and crush it in the mortar with the pestle. I
would mix that 50-50 with some MnO2 from a battery and add the 1%
antimony sulfide. That would reduce the graphite concentration and
start the electrode from a 'less overdischarged' state.
I put 30 grams into a small beaker and added water. A
little stirring brought the bubbles of hydrogen up and turned the water
grey with Mn [hydr]oxide. The strongest reaction proceeded over a few
minutes in cold water without noticable heat. The water would clarify,
but for several hours, each time it was stirred, tho decreasingly, more
bubbles would rise, perhaps showing it was fairly close to not self
even without any additives. I wasn't sure all the powder converted -
perhaps a skin of oxide formed on the outside of each grain, protecting
the interior. (Aluminum does that in neutral pH, and even in air.) Oh
well, close enough?
Monel or nickel powder would have made no bubbles; zinc,
few to none; magnesium (~ -2.5 V) might have frothed violently (as does
aluminum in alkaline solution (-2.33 V), making a lot of heat); sodium
(~ -3 volts) would have virtually exploded when the water hit it.
But after this supposed 'conversion' to oxide, the powder
still weighed 30 grams. Losses of material in pouring and handling were
minor. Obviously MnO or Mn(OH)2 with the same Mn content should
have weighed more than the original Mn (38 or 48 grams), so the
conclusion is that not much of it reacted and it's still mostly Mn
powder. Probably the skin of oxide was formed on each particle,
preventing interior oxidation. Either that, or the stuff just wasn't
self discharging... but why would some do it and not all of it?
I tried grinding it in the mortar and pestle, but when I
added water again, there were few bubbles. I suspect it wouldn't give
1/10th of the theoretical amp-hours rating because, small tho the
grains were, only their skins would react. So I decided to go with
straight salvaged dry cell MnO2/MnOOH despite the excess graphite
(probably totally unnecessary) and the 'overdischarged' initial state.
(So much for the pricey tin of Mn powder.)
So I measured out 40 grams of salvaged dry cell MnO2. It
bulkier and probably was about 35% graphite, leaving 26g of MnO2 or
16.5g of Mn. At 951 AH/g of Mn, that's a theoretical 15.7 amp-hours.
(I'll be extatic if it gets 5. Of course, I'll be extatic if the
battery works properly at all!)
1% Sb2S3 would be .4 grams. That's more than 1% of the
MnO2, but some will be next to the graphite instead of the Mn, and it's
not very fine powder. Now the
rock is maybe 2/3 quartz, so that's 1.2g of finely pulverized rock to
add. Maybe 1.5 or 2 for good measure. The piece I pulverized made 1.65g
so that's what I used.
I also decided to add 2% (.8g) "vee-gum" (a bentonite clay
mix, sometimes used to thicken lotions and creams) to act as a
binder/glue (having no PTFE or PVA). I don't think there's any binder
used in dry cells.
I ground this mix with mortar and pestle. I continued
quite a while as I could hear particles being ground finer.
Finally the visible white bits (vee-gum) in the black mix became tiny,
and few and far between, and I figured the antimony must be about as
ground down and spread around as it was going to be.
Well, it had graphite, so I used diesel-kleen to wet it
down, 2 grams. When this was well mixed in, I put 1/2 into the
compactor, inserted the the current collector screen with terminal
wire, then the other half of the mix.
I finally got to try out the book press for compacting
electrodes. It was probably about as good as the "bolts around the
edges" compactor, and somewhat less work, tho I certainly had to crank
it hard. (It was tempting to use a pry bar, but I didn't want to risk
breaking it - it's not even mine.) The electrode measured around
100-120 Ω or more between any two
points. A clump of salvaged dry cell measured around 30+... at least 3
times more conductive. They may get better compaction at the factories,
but it's also possible conductivity gets better after sitting a while,
after electrolyte is added, or when the cell is in use. Certainly
rechargeable electrodes seem to harden up with a few cycles, and the
manganese should also conduct better as it charges to a lower oxide and
then to metal.
However, the punch jammed in the die and I had to hammer
it through. This broke up the electrode, the top half separating from
the grill, then breaking into 3 pieces. I would have tried again, but
even the bottom half plus the screen was 4+mm thick, so I decided to
use that as it was. Graphite sure adds bulk!
And the grill must have scraped against the side of the
compactor - bare copper was showing. Since it was at the bottom on the
far side from the terminal connections, and since it was the negatrode,
which would corrode much more slowly, I decided it should last long
enough to tell if the manganese worked properly or not. The leftover
grafpoxy in the freezer wasn't quite hard yet and I managed to touch it
up a bit, but there's no guarantee it's fully covered.
Hmm... Diesel Kleen contains trimethyl benzene... toluene is
methyl benzene. Am I doing the same thing twice, first using the one
during compaction, then pouring a little of the other on to soak into
the finished electrode?
For a positrode, I used a slight variation on the mix that
gave the rather successful nickel-zinc battery in October (TE News 45).
15g monel mix (AEE monel)
3.0 diesel kleen
This one gave resistance readings in the 20's of ohms
range. It would probably go up as the monel charges to nickel hydroxide
& copper oxide.
Ni (L) & Mn (R) electrodes as compacted
After painting Ni with Ca(OH)2 and torching
The water of painting brought out KMnO4 purple color
As the 'trodes were drying in the toaster oven outdoors, I
realized there was no way I could torch them with the grills exposed,
even underneath. I'd be bound to burn off some grafpoxy around the
edges. But they both came loose from their grills... Ugh! So I torched
the front face of the loose briquettes.
I've been looking for finer grilles - maybe I should be
looking for coarser so the briquettes don't split apart at them. On the
other hand, the 3/8" wide foil section with the rivets at the top is
probably the real culprit that got the splits started.
I did the separators and put everything into the acrylic
case. Then I slid a piece of plastic behind the positrode to take up
some of the remaining slack space.
I filled the cell and left it to sit overnight. In the
morning, the purple permanganate color in the water at the positrode
had been replaced by solid green-blue of nickel and copper oxides: the
monel, oxidized - and hence swelled up - by the permanganate.
Resistance had increased to over 1 K Ω to the terminal - ugh!
At 2 PM I added a bit more water as the level had dropped
a bit, and put on a 15mA charge. After 10 minutes and with the cell at
only .7 volts, I decided that was too timid and doubled it.
The voltage drop when the charge was removed suggested
that the overall internal resistance was about 15 ohms - ouch! (.45 V /
.03 A = 15) 1% that high would be nice. Perhaps it might improve with
charging... but I've hoped that before in vain. (It didn't.)
Certainly having the briquettes split in half and coming
loose from the grills can't be good. I think a finer grill and wire
that I can tack weld should be better than rivets and the copper foil.
Then, mashing them into place with no spaces left over at all should
prevent them from swelling up so much. The most successful cell was the
one where the positrode had the least space to swell into before it was
In fact, maybe what I need to do is wet them while held
together, and leave them for a day or two before trying to insert them
into the cell at all. Then they should start to harden up and should be
less prone to swelling once inserted.
After 24 hours the cell was still only up to 1.4 volts on
charge, up from 1.0 initially, and dropped quickly (~1 minute) to about
3/4 of a volt when the charge was removed. Well, that would come with
starting with both electrodes in an "overdischarged" state and charging
The 'idle' and 'load' voltages were read when the voltage
drop decreased to less then 1mV/sec.
10m 1.0 volt on charge (14th)
24h 1.4; Idle: .75; 100 Ω Load: .67v
48h 1.7; Idle: 1.09; L: .77
56h 1.84; I: 1.28 ; L: .94
72h 2.29 (66Ω); I: 1.51 ; L: 1.12; pH 13
96h 2.19 (82Ω); I: 1.59; L: 1.19; pH 13
120h: 2.29 (66Ω); I: 1.62: L: 1.24; pH 9 or 10 (19th) - it went back up
to, um, probably it was 12.3
After that only minor voltage changes were seen. Like some
of my other cells with high resistance, it wouldn't hold anything like
the expected voltage, but it would deliver small currents for hours at
voltages below a volt. (The voltage of NiOOH + Mn(OH)2 is +.49 - -.25 =
.74 volts, with the Mn(OH)2 discharging to Mn2O3.)
After 3 days, it finally occurred to me to check the pH of
the electrolyte of my neutral salt solution. The bubbling Mn- was 13!
Let's see... I put in Mn in the '+' side as KMnO4. That would reduce to
MnO4, leaving K- and 2O--. The spare K would "obviously"
form KOH, making the mix alkaline. I added a few drops of HCl to change
the KOH to KCl - my salt. The bubbles 'instantly' vanished. It went
down to pH 8 or 9, apparently the desired range from the pourbaix
Then I checked the other side of the separator, where I
had also dripped a few drops of acid. pH was 1! Let's see... pH 1 on
the positrode side, and 8 on the negatrode. But that was just dripped
into the surface water above the electrodes. After a while they were
coming back into balance. The next morning it was back to 13, on both
sides. I added a couple more drops of acid, but in a couple of hours it
read 13 again. I did it again in the afternoon.
On the 19th I figured out the likely answer: calcium
hydroxide is only very slightly soluble, but the bit that dissolves
imparts an alkalinity of 12.3 in clear water. That must be reading as
"13" to my broad range pH paper test strips. Thus, the pH is bound to
stay at 12.3 until the Ca(OH)2 is all converted to calcium carbonate by
atmospheric carbon dioxide or other reactions.
But what did I want? The idea of putting in calcium
hydroxide was to have it set like cement as calcium carbonate to make
the surface of the electrode hard, not to have it make the electrolyte
But according to the newly found Pourbaix diagrams, All the chemicals
should definitely be
solid at pH 11-13. It should be better than either neutral 7 or
'totally' alkali 14. Perhaps I should want
a "somewhat alkaline" battery? If I want the cells to be pH 12.3, I
should add the lime. If I want them at neutral pH, I should leave it
out, or be sure the calcium turns to carbonate before putting the cell
into the battery. Either way, I'm sure the cells definitely should be
as sealed or as separated from atmospheric air as possible.
Let's see now... at pH 12.3, it looks like the Mn should
be about -1.4 volts, and the nickel +.6, total 2 volts. At pH 7, the Mn
should be about -1.2 and the nickel +1.1 or so, total 2.3. After 5
days, the cell didn't seem to want to charge to either of these figures
and both electrodes were bubbling. Perhaps it was time to make a new
case with a good lid, and a new cell, trying out the "wetting while
compacted" to prevent the positrode from swelling and losing
I must say working with salt electrolyte is more involved
than just O.D.ing everything with acid or alkali, pH 1 or 14. Put the
right things in potassium hydroxide, they just work, and they seem to
hold a charge. The oxalic acid cell worked. No wonder earlier
researchers went along those lines - to them, getting something that
actually worked, in a reasonable time frame, was the main goal.
Salt... It's hard to get it going and hard to get things to hold a
charge, and the pH is a big variable. But there's a wide field of
potential chemistries... and standard ammonium chloride dry cells
obviously do work. (A friend who once experimented with them says
they'll recharge once to about
70% of original capacity. After that they leak.)
So, Alkaline experiments...
I'd been thinking for some time of a couple of
experiments with zinc and manganese in KOH solution, for which I could
use some of the nickel electrodes and the case of the nickel-iron cell.
With the zinc, the experiment would be to wrap the electrode with paper
painted with zirconium silicate as an ion shield and see how it holds
out over time. With the manganese, it would be to try out an Mn
electrode with Sb2S3 as the overvoltage additive and see if it works in
an alkaline cell.
The first one to try was the Mn - also with the zircon
wrap. If that worked well, future Zn alkaline electrodes might be
rather pointless since Mn is higher energy (both volts and amp-hours),
just as cheap, and long lasting. According to the dual alkali &
acid electrochemical chart, the Mn would maintain solid forms at all
points of charge and discharge. According to the Pourbaix diagram it
would form Mn(OH)3- instead of Mn(OH)2, and dissolve. If it worked with
the zircon, next I'd try it without, since according to the first chart
it shouldn't need it.
(R) Pocket electrode from nickel-iron battery, some iron filler behind
(L) Replacement brass pocket with Mn electrode for test
On the 22nd I tried to dig the
iron out of an iron pocket
electrode to replace it with the manganese, but it was tough going.
Probably it was charged to iron particles that would be sintered -
electroplated - to the pocket walls. Fully discharged to Fe3O4 it
should have been easier.
So instead I made a new 'pocket' from perforated brass.
The holes are huge compared to the originals and I hope the stuff
doesn't leak out. It was also much heavier - the original metal pockets
are almost as thin as a foil, so they didn't add a lot of weight. My
opinion of pocket cells as a battery construction went up a notch or
two. I remixed and compacted the Mn that had fallen off the Mn with
stibnite electrode made above. If my calculations above are right,
it should have 6 or 7 amp-hours of juice. But the nickel electrodes I
coupled it to were only 5, and I was only filling the cell half full
since this electrode was half height, so it would be lucky to have
three, limited by the nickel.
The cell started with a very low voltage. The Mn was
'overdischarged' MnO2 and had to be charged first to Mn(OH)2, then to
Mn metal - twice as much as a regular charge. The nickel would be
bubbling O2 before the Mn would start to bubble hydrogen! The reaction
MnO2 to Mn2O3 is +.15 volts. Mn2O3 to Mn(OH)2 is -.25 volts. Mn(OH)2 to
Mn(0) metal powder is -1.56 - the high energy reaction. The initial
voltage was around .3 or .4 V: +.49 - +.15 = .34 V. Then it would be
higher voltage: +.49 - -.25 = .74 V. I figured the charge voltage would
climb gradually from around .55 to .9 volts, and then climb rapidly to
the 2.05 V area, as .49 - -1.56... if it worked. At 50mA charging
voltage did rise over the hours from about .5 volts in late morning to
.7 at bed time. At that point it would already supply a steady .55 A
into a 1 Ω load.
In the mirror I had noticed a tiny spot on my nose
bleeding. It didn't look like a bug bite and wasn't inflamed. I
couldn't remember anything hitting me on the nose. Hours later I looked
and it was bigger. It then dawned on me that a tiny drop of potassium
hydroxide must have splashed up and hit me on the nose, little tho I
was using and carefully tho I'd poured it. (I did have safety glasses
on.) A small drop - what nasty stuff! This is a good reminder why I
make salt electrolyte batteries.
The next afternoon, the cell voltage was still rising
(.85v), but it didn't seem to supply current as well. I opened the cell
and saw the purple color of permanganate in the water. The pH had
dropped to 13 or less. The most likely scenario would seem to be that
the Mn(OH)3- ion shown in the Pourbaix diagram had indeed formed,
zirconium ion shield, touched the positrode, and formed KMnO4, reducing
the level of KOH until the pH dropped to 13, whereat the Mn(OH)3- ion
ceases to form.
The question was whether the cell could work well like
that or not. The nickel plating and then the metal underneath on the
positrode pockets might well dissolve - it certainly would at pH 10 or
11 or less. This could be solved by a new cell with grafpoxy electrode
structures. I hoped the cell would last at least long enough to see how
the chemicals worked and if the 2.05 open circuit volts would appear
and not discharge itself within minutes or a few hours.
The nickel Pourbaix diagram shows nickel also working best
at pH 8.2 to 12.6, and again this isn't indicated on the simpler
That would mean that except for the potential dissolving of the
electrode structures, the chemicals at the lower pH should
charge and discharge indefinitely. It might also mean more weakly
alkaline cells would have
substantially lower self-discharge than at pH 14. The current capacity
for a while seemed reduced with the drop in KOH electrolyte
concentration. But by late evening the cell crossed the 1 volt mark and
capacity was improving - over .7 amps into a 1Ω load.
The third day I found it would start supplying over an amp
and then continually drop until it hit about .74 volts, where the
voltage became steady. That
should mean that the Mn was now pretty much fully charged to Mn(OH)2,
-.25 volts. That would be NiOOH-Mn(OH)2 = +.49 - -.25 = .74 volts. I
found it would drop to about this same voltage with either a 1Ω or 2.2Ω
resistor, suggesting quite good current capacity. The initial higher
voltage was presumably from the small portion charged to Mn metal. As
the day went on and the voltage rose, it seemed to take longer to drop
from the rising voltage to .74V - but not very long. I increased the
charge to about 65mA. The pH remained around 13 and the water color
slightly purple. The nickel plated positrode pockets didn't seem to be
dissolving. Still no bubbles were visible - good signs!
By three days charging about 4 amp-hours should have gone
into the cell. Since the voltage was well above .75, some of the MnO2
must have passed the Mn(OH)2 state and charged to Mn metal. So the capacity of the Mn is somewhere below
4 amp-hours. A few bubbles were seen. It was hard to tell, but I
thought they were from the nickel side. Specific gravity of the electrolyte was about 1.22, so the
permanganate hadn't notably diluted the KOH. The charge voltage seemed to stop rising at
about 1.65 volts... surely it should get closer to 2? Notwithstanding
the slight pH shift, nickel-zinc charges to 1.8, and Mn should be about
1/4 volt more.
It then occurred to me that the perforated brass 'pocket'
containing the manganese might be a problem. The brass had no
overvoltage additive, and might well bubble hydrogen at that voltage. I
suspected I had a good cell with a bad exterior pocket material.
no guarantee that the original steel pockets would work at this high
negative voltage, either... except that evidently they do work with
The battery seemed to run perfectly, except at the .74
volts level instead of 2 volts. After about 10
hours discharge into 5Ω, well over an amp hour, it was still going
great. Internal resistance as discerned by the voltage drops at
different loads, might be estimated at around .1Ω.
Obviously the next try should be a Mn electrode with a
grafpoxy grill to eliminate the brass piece. I took the previous cell
apart and used that one. The first result was quite clear: the
conductivity of this electrode was crap, whereas the one in the brass
cage had been excellent. It had expanded within the first cell.
Conductivity is the first thing that needs to be made repeatably
reliable, irrespective of chemistries.
The second result also seemed quite clear for a while: the
voltage rose about the same as the first cell, to around 1.6-1.7 volts,
and started bubbling. I didn't really understand this, because zinc
charges to 1.8 volts, and Sb2S3 should be a good overvoltage raiser.
Even if the Mn wouldn't charge to metal or discharged too quickly to be
of use, I thought it should go over 1.8 volts or so before it started
One idea was that the pH could be further
lowered, as the Mn voltage drops from -1.56 to about -1.15 volts as pH
goes from 14 to 7.5. Hydrogen voltage drops too, but not so rapidly.
But one last thing to try first was to up the charge and
let it bubble. After all, I expected that the antimony was likely to
convert to keresemite, which might have a higher hydrogen overvoltage
than the stibnite, so the test wasn't fully complete until a long
charge has been made, to either have that happen or be sure it won't
work. I dropped the series resistor from 56 to 27 ohms. The voltage
went up to 1.84 (and stayed at about that level), and I found the
current was only 61mA - so actually I'd only restored the charge to
around its original current, at the higher voltage. (I probably should
be using the lab power supply for charging instead of an old power
adapter and resistors. For that I need a bigger counter space to work
In an hour it was holding higher voltages from 1.7 V down
much longer, but not really stopping and stabilizing anywhere. After
another hour I dropped it from 27 ohms to 10, and 115mA current. The
voltage hit 1.9. In another hour it was down again to 1.82, and when
disconnected dropped still more slowly from about 1.8 volts. It also
stayed up longer and higher with a 10Ω load. Increasing conductivity as
well as increasing voltage pretty much meant the manganese had to be
charging from hydroxide to metal. In another hour the charge was back
to 1.9, but it held 1.82 volts open circuit, and almost 1.75
discharging at 175mA for about a minute.
On the 28th I disconnected it for a couple of hours.
Voltage dropped to 1.38 volts and it had little energy left for
discharge. I tried upping the charging current to 710mA. The charging
voltage rose to over 2 volts, and it started discharging from 1.9+ with
good supply. So it would charge if driven hard enough, but it had the
usual rapid self discharge. But the voltage stayed higher more easily.
Perhaps the keresemite was still forming. However, the boiling had
partially broken up the electrode, and the water was black with
manganese oxides. pH was back to 14.
Another possible reason for
high self discharge occurred to me: the Sb2S3 was simply mineral ground
from a rock. It might well be that on a milli- or micro-scale, that
there were 'chunks' of it in one place and other places where it was
missing. The missing spots would continue to have the spontaneous self
discharge, gradually dragging the whole cell down.
I decided that in spite of considerable bubbling and self
discharge, the cell probably was essentially working. The stibnite
powder had arrived on the 26th, so the next step would be to make
another new Mn negatrode with fine stibnite powder in it.
Envisioning a Production Battery Construction
New idea battery case with next Mn electrode installed.
Separator paper goes on top.
This would be molded piece #1.
imagining a number of possible
molded plastic shapes, lightweight "pocket" cages with the vertical
perforated sides, or a grid lattice holding in paper sides, to hold the
electrodes and prevent them from
expanding once inserted into the cell, which appears to be my ongoing
main problem. These, or perhaps even a bezel, might also make handling
and inserting the electrodes simple, including for DIY production. And electrodes with internal grafpoxy coated
grills - or even nickel plated grills - should be cheaper to make than
nickel plated pocket cells. This construction could be applied to any
fillings chosen, so it should be
worth it for somebody to set up some sort of production line to make
batteries in that form without waiting for any other battery success in
my research. (Making a mold(s) for this seems like a fine job for my
new milling machine!)
With paper, and vertical bars glued around edges (where paper might have
a gap). Ideally bars would be a four-sided frame, taller than the
and with finer, closer spaced bars.
consideration, I decided that maybe making the
cases to exact 'bezel' size but leaving one side off might be the
simplest. The bottom electrode, exact size separator paper, a frame of
bubble path bars (glued around the edge), another separator, the top
electrode, and something springy if any space remained, would all be
layed gently into place without the likelihood of breaking the
electrode briquettes, then the
other side would be clamped on top and glued. Then it would be set
upright and the top glued on. The more of the four plastic pieces that
were pre-molded, the
easier it would be, but it could all be glued flat pieces.
Known reliable chemistries like nickel-iron or nickel-zinc
should work without issues and provide perhaps 40-70 or 70-100
watt-hours per kilogram. If battery lids were made to screw on, with a
rubber gasket, the cells could be opened and the zinc electrodes
cleaned off or replaced when necessary.
Of course nickel-manganese will be a better choice if it
works - I'm optimistic that it will if done right, and that they'd get
90 to 120
WH/Kg. That's not as high as lithium ion, but it's better than
lithium-iron phosphate (60) and better than NiMH dry cells (70-100). I
would use the watercolor paper separators, but (borrowing from pocket
electrode batteries) put in a plastic frame having about 4mm spaced
vertical bars and no cross members except at the top and bottom, between and (maybe) behind the electrodes, thus creating small liquid filled vertical
spaces beside the bars, to allow bubbles to rise to the surface in the
event of overcharging. In fact, that would be the only place there'd be
straight liquid except to have enough over the tops of the electrodes
to immerse them.
If steel pockets work okay with manganese,
nickel-iron battery makers could simply put an Mn(OH)2+1% stibnite mix
their cells in place of the Fe3O4 - then they'd
be making about 1.8-1.9 volt
cells instead of 1.2 for about the same cost and with no real changes
to their assembly lines. 60%
more energy would yield 50 to 80 watt-hours per kilogram batteries
instead of 30 to 50. That's within present electric vehicle
and the current capacity with manganese seems notably higher than with