Turquoise Energy Ltd. News #53
Victoria BC
Copyright 2012 Craig Carmichael - July 2nd, 2012


http://www.TurquoiseEnergy.com = http://www.ElectricHubcap.com = http://www.ElectricWeel.com

Hilights:
- The Mushroom Electric Outboard Motor [Design]
- 3D plastic printing to revolutionize home battery making

Month In Brief
(Summaries)

In Passing (Miscellaneous topics and editorial comments)
- War on Greed - Mercy & forgiveness - How to stop the Peace River Site C Dam

Electric Hubcap System
* Improved Outboard From Scratch Design: The "Mushroom Outboard"!
* U-joint 90º Drive - socket wrench U-joints - tests show it works fine.
* Sprint Car: Torque converter is ready; needs motor, controller, batteries.
* New motor plate drill templates: from hand calculator to... spreadsheet G-code.

Planetary Gear Torque Converter Project
* Planetary gear torque converters are already in use! - Toyota Prius & more.
* Sprint 'clutch' linkage installation.

Solar Electricity Project
* Modules of the "DC Grid Tie" unit.
* Solar Hot Water addition (doubles electricity savings) - plastic/rubber mat collector, & Pump Control Module.

Turquoise Battery Project
* RepRap: 3D printing of plastic parts will create battery making revolution
* Conductive carbon fiberized ABS printing plastic for positive electrodes ("posodes")
* 3D electrode pockets from Camosun College/VICAMP
* Next Mn negative electrode ("negode") with latest everything
* Mn negode doesn't work in KOH electrolyte (pH 14) - discharges spontaneously
* Mn negode does work in KCl electrolyte (at moderately alkaline pH)
* Cells need seal to keep O2 out to prevent self discharge

No Project Reports on: Magnetic Motion Devices, Weel motor, LED Lighting Project, DSSC solar cells, Pulsejet steel plate cutter



Newsletters Index/Highlights: http://www.TurquoiseEnergy.com/news/index.html

Construction Manuals and information:
Electric Hubcap Motor - Turquoise Motor Controller
- 36 Volt Electric Fan-Heater
- Nanocrystalline glass to enhance Solar Cell performance - Ersatz 'powder coating' home process for protecting/painting metal

Products Catalog:
 - Electric Hubcap Motor Kit
 - Sodium Sulfate - Lead-Acid battery longevity/renewal
 - NiMH Handy Battery Sticks
, Dry Cells
 - LED Light Fixtures
Motor Building Workshops


...all at:  http://www.TurquoiseEnergy.com/
(orders: e-mail craig@saers.com)



June in Brief

   I can hardly believe that I've taken on yet another project, a 'novel' solar electricity system, following so soon on starting to explore magnetic systems, and with quite a number of unfinished or not quite finished projects still on the go... and when I seem to be waking up every morning with a boundless supply of lethargy, then tiring out by mid afternoon. (Perhaps a holiday would help? ...Hmm, B vitamins seem to help) Yet all these fields seem so ripe for the harvest, and the workers are so few, that the temptations are irresistible.

   With western quasi-democratic civilization apparently being ripped to pieces by ever more heinous financial and political crimes, I spent considerable time trying to make sense of it all and encapsulate my view of the big picture in an editorial (below), "War on Greed".

   I hoped I could get the solar collectors mounted in a week, and then pick away piecemeal at the electronic and electrical aspects of the project while I got back to finish or at least to progress on other things. But safely mounting them on a south facing roof with a 45º slope 26+ feet above ground would be no trivial undertaking, and the prep, pursued at first part time and then only occasionally, drew out for an extended period. Finally on the last day of June I finished a scaffold-ladder to hook over the peak and lie on the roof of the house. Most people with shorter houses and flatter roofs, or a ground area to place solar panels, would have a much easier time of it. My south roof is an excellent location and angle, but putting the collectors at the base of the house in the tree shadows was looking very attractive. On July 1st I climbed a hill and overlooked many homes... none with solar panels. It needs to be made easier and cheaper. The panels are good enough: The things that go around them need work, and need to be affordable.
   The hot water tank "dump load" idea meant there'd be a hot water preheater tank, which I decided could go in the upstairs bathroom next to the regular water tank as part of remodeling that bathroom. In for a penny in for a pound... I bought a dual 2' x 10' (4 square meters) plastic mat "swimming pool" hot water solar collector and DHW circpump for a bill of around 500$. The hot water tube panels should heat the tank at least as well as all four electric panels if not better, doubling the electricity saved for 1/4 of the price. Other motives for this addition were to cover up the shingles coming apart at the far edge of the south roof (the first PV panel does the other edge) and stave off reshingleing a few years (10?), and to create and test an optional "module" for the DC Grid Tie box: a differential temperature pump switch module.
   Of course, getting the panels up will just lead to more work to get everything running.

   Meanwhile there was the unfinished new motor for the stripped Honda Electric outboard. But it didn't look like a new Electric Hubcap motor would fit readily under the Honda hood. I could make a new hood... ugh! Then I thought up a "U-joint" design to mount the motor at a 30º angle... and then I thought: maybe U-joints could be used to transit the shaft rotation from vertical to horizontal down at the prop, eliminating gears or pulleys with belts or chains. A test with socket wrench U-joints showed it was likely to work smoothly without much friction. (Contrary, as is often the case, to all advice on the matter.)
   With this exciting design idea, I decided it would be better to do the "outboard from scratch" which could then be replicated, and forget putting time and energy into the "one off" Honda. Unfortunately, this meant calling the fisherman to say things couldn't be ready this season, so I was delaying or perhaps defaulting out of a promising sounding contract - rats! Making a mock-up of the design suggested a name - the Mushroom Outboard. I concentrated on getting the U-joint 90º drive working nicely and figuring out how to mount its pieces.

   In a period starting around the middle of the month, I did much shopping at odd locations, mostly for the projects. I made several visits to Camosun college's VICAMP facility where they 3D printed me some 'perforated' ABS plastic electrode pockets, and in general somehow I seemed to spend my days driving around rather than getting any work done. The second batch of pockets on the 15th looked quite usable, so with zinc and grafpoxied carbon fiber current collector plates, I was ready to try making a decent test cell. Camosun's bill however came to 325$ and I was glad I had ordered my own 3D plastic printer (and some ABS printing filaments in several colors). By the time it arrives and I get it assembled, I'll be wanting to make electrode pockets, cases and pressure seal/relief caps.

   Having the electrode pockets, I turned some MnCO3 into MnO to make a 'negode' with a solid sheet zinc (from a dry cell) current collector. Theoretically the MnCO3 could be 'calcined' to MnO at the low temperature of 200ºC, but it didn't work "as advertised" on Wikipedia... nor at 230 or 260º... and in the end I sprinkled the powder through a propane torch flame 3 times. Hmmf... I could as easily have reduced MnO2 to MnO by the very same technique!
   I put the completed Mn electrode into the Changhong cell together with two NiOOH electrodes, making a Ni-Mn cell. The conductivity was much lower than for the sintered electrode... it seemed to work, but finally I realized the voltage (1.8V) was too low... the active chemical was actually the zinc current collector and current raising zinc powder rather than the manganese. The manganese wasn't charging, and if enough current was applied to force it to charge, it soon discharged back down to 1.8V, where it stabilized.
   So I put together a whole Mn-Mn cell and used KCl electrolyte. This soon charged up to 2.25 volts, which very gradually dropped to around 2.15 V idle, notwithstanding liquid leaking out the top corners. Longer charging (days) brought it up to around 2.4 volts. Zinc would have been around 1.85 - 2.0 volts, so the manganese had to be charging. Gradual self discharge over many hours is probably explained by air leaking into the cell - oxygen discharges alkaline negative electrodes.


Yes the meter is accurate - it's a whole volt higher than most alkaline cells.
No the cell isn't on charge. (It was a few minutes previously.)
Yes it's one single MnMn 'moderately alkaline' battery cell.

   The ABS filament supplier, 'Voxel Factory', mentioned a conductive ABS filament with carbon fiber in it. He tried to get hold of some, but finally said that for all the hype, he was unable to get the fiberized plastic. Rats! I started trying to figure out ways of impregnating carbon fiber and zinc into the insides of finished ABS electrode pieces as a conductive liner.
   It seems best now to put the batteries on hold until the 3D printer arrives. Then things should become much easier to make. Indeed the whole idea of 3D printing homemade battery parts (using any alkaline type of chemistry) looks so much simpler as to probably amount to a battery making revolution.

   I also got the 'clutch' cable and slip control rope assembly installed in the Sprint car. I hadn't been sure how I was going to do this until I finally thought of using a small rope and pulleys to go between spacially unrelated points 'A' (slip tension rope) and 'B' (shift cable).


Control Clutch (ex gearshift) cable linkage to Slip Control V-Belt pulley
via small rope & 2 small pulleys
(Yes, it could be tidied up. I wanna see it work first.)

   With the car being now ready to test except for a motor, controller and batteries, I finally got the stator plate drill template worked out and drilled the holes in the waiting motor parts just before month's end. I fooled around with CAD programs and "DXF to G-Code" converters without much luck. Then I simply entered the text of the main body of the G-code into spreadsheet cells appropriately interspersed with the co-ordinate calculations, then just cut and pasted it into the program file, eliminating most of the grunt work. At last, a way to simplify it!
   I need to put together at least a couple of motors and controllers at this point. For a guy that wants to sell motor kits and controllers, I sure don't seem to be producing them very fast!



In Passing
Incidental news, editorials

- Wanted: War on Greed, Corruption & Violence - Mercy is the way to peace & progress - Are Universities Superfluous?

   Without a serious enemy in the world, USA's "leaders" are fond of declaring futile, never ending wars. At home: "War on Drugs"; "War on Poverty"; "War on Terrorism". Abroad: bribes, threats, assassinations and other "power plays", and trumped-up excuses for invading, occupying and plundering weak countries. For personal gain and power, they have been fabricating trouble and creating artificial problems to fight an increasingly effective undeclared war on the long cherished rights and freedoms of their own citizens. This cancer has been festering for a long time, and is now malignant, rapidly spreading - the perpetraitors are now in almost complete control. They are intent on turning America into everybody's enemy, the global bully, enslaving their own citizens at home and stirring up trouble all around the world. Psychopathic "major scandal" level offenses by those in economic and political control have overwhelmed the defenses of law and order. Canada and seemingly Britain and Europe are now trotting along beside the USA in her path to ruin like Italy did Germany in world war two, eager to outdo her in malicious malfeasance. But it would seem they are all trotting along as the puppets of the multinational banks and other entrenched corporate evil empires - the ruling "cleptocracy" as it's coming to be known. The earnest attempts of citizens with ideas and ideals to bring about justice, order and progress are ignored, even branded 'terrorism' and maliciously suppressed, while far too many thoughtlessly while away the hours watching entertainment TV, ignorant of the turbulent currents swirling around them. Western civilization as we know it has apparently reached an evolutionary dead end.

   With the new interconnectedness of the internet, people around the world are just starting to wake up to the fact that everyone everywhere is caught in plights to related to their own, and that except for small agitating and greedy minorities everywhere (mostly in control), they are mostly goodhearted people who have no evil plans for jihad against anybody else. But no one is safe until everyone is safe. The most powerful nation can't protect its people against someone who has nothing more to lose with a homemade bomb strapped to his belt. At some point, everybody, everywhere, including those pulling the strings - or their children - will start to sicken of this fools' game and turn long nurtured energies of fear, hatred and greed to love, to the bearing of fruits instead of thorns. There are small signs that attitudes are everywhere starting to change.
   But even those ultra rich who already want change just don't know where to start. The way things are going, seemingly from bad to worse to worser, what could possibly trigger favorable outcomes? Unpleasant scenarios of conditions inimical to progress like widespread rioting and mob actions come readily to mind. "Those who make peaceful evolution impossible make violent revolution inevitable." - John F. Kennedy

   But the pendulum may be reaching its maximum swing because the global currency system seems about ready to crack. Many analysts have been warning for several years of bank frauds and scams on the global scale. A rapidly growing number of people have now joined them in saying financial collapse, whether imminent or staved off until later, is now inevitable... and that it's a necessary evil.
With western media being beholden to the corrupt, the only news network covering this, seemingly the biggest story in the world, is rt.com.
   Those in control of the biggest banks are now openly manipulating everyone to economically pillage the world, stealing every fund including peoples' retirement savings and even from their bank accounts, and driving whole nations to economic servitude and ruin. (Canadian bankers are evidently not innocent, BTW.) Having acquired nearly all the fiat money for themselves and realizing that this very fact is making it worthless while also dropping property values, they're now trying to steal the last things likely to hold their value - gold and silver. (They seem to have set their sights on Greece's and Italy's gold now.) And they pay off the leading politicians - or in fact are doing what the politicians want - so (except in Iceland) they aren't being arrested or reined in. No banker will today invest in a productive enterprise: stealing money is easier and more profitable.
   If the banks close (AKA 'an extended bank holiday'), and if fiat currency collapses, along with many destabilizing and perhaps devastating effects, all the entrenched vested interests will probably lose their economic stranglehold. An unsettled and turbulent but potentially fertile period will likely ensue, when all sorts of beneficial changes unimaginable under today's repressive conditions can take place.
   Then people can start working together, to tackle the roots of the real problems: to find and adopt sustainable social, political and economic systems that citizens actually have effective control over. If there are wars to be declared, they'll be "War on Greed", "War on Corruption", and "War on Warmongering" - which "wars" will really just be the long overdue corrective operation of the presently dysfunctional wheels of government. If institutional and societal changes create conditions unfavorable to empowering rogue elements and draw most everyone over to the same side, working towards the same goals of a new, sustainable civilization, then the world will begin to draw together and become peaceful, prosperous, and sustainable. The brotherhood of mankind will be dawning.

   The contribution of each individual defines the whole. For the immediate future, in order to be in a position to contribute rather than to be in personal or family need, the advise of those in the know is to have money in cash, put aside good food and other necessities, and buy some silver and or gold. (eg: there are coin and bullion dealers in every city, who sell 1 oz pure silver coins, at about whatever silver is currently valued at plus some mark up.) I don't think anyone should do anything rash or irreversible, or panic, but the more people who are prepared to weather an initial shock of closed banks and disabled or empty ATMs, with the likelihood of empty grocery stores, the better for everyone. Ongoing major withdrawals - gradual bank runs - are already on in Europe. At the moment, if confidence in fiat currency fails and suddenly the banks close, it appears likely to catch 99% of the population by surprise.
   I've heard it said that simply thinking about it and withdrawing money to prepare will cause it to happen. If the world banking system is that bankrupt, it can only affect the timing a bit, and will seem poor logic later if you have nothing to eat.

   I regret feeling the need to have written this piece, and I'm aware that it may possibly be many months premature, or that things now broken will get fixed and in a year or so I may look like an overreactive fool. But having seen a glimpse of what appears to lie ahead and may be triggered imminently, I need my conscience to be clear if people are suffering for want of preparation, that I passed on the warnings of many seemingly good judges of finance and economy as best I could.

---

    In the middle of the month, I heard rumors of grand plans to reorganize the world's money system when or if the banks shut down. When you bring in your cash, you'll get to trade it in for the new money. But when you bring in your six billion dollar bank account, questions will be asked... like where did you get the money?, and, is it a reasonable amount for you to possess? This is about the most hopeful thing I've heard for some time.
   If the rumor is true, it might help to explain why so little seems to be being done to combat the financial terrorism: many people have decided that the sooner the whole system crashes, the sooner it can be fixed. Such a plan, if it really exists, tho it could hardly be implemented in a day or a week, could do much to mitigate and shorten the unsettled period, and to improve the likelihood of good outcomes.
   But I fear it sounds like wishful thinking - too good to be true.

---

   Some Egyptians were demonstrating early in June, calling for vengeance against Hosni Mubarak and his family and the people formerly involved in running Egypt. Yet Mubarak simply 'inherited' dictatorial power when Anwar Sadat was murdered. As far as I can tell from what little news ever reached the west, his long regime was pretty peaceful, even uneventful. Egyptians who stayed home may be grateful to him for stepping down peacefully instead of fighting it out to the end - and maybe winning - with all the bloodshed, turmoil and ruin that would have ensued.
   Punishing Mubarak and those around him will only ensure that others having power, all around the world, will never dare to step down and will have to be removed, if at all, by ultimate force. The protesters want more violence against him than he was willing to unleash against them. It is the wrong signal to send. Mercy and forgiveness - especially to those who surely have only tried their best according to the lights given them - are the paths to peace, progress and prosperity. "Blessed are the merciful, for they shall receive mercy." "Blessed are the peacemakers, for they shall be called Sons of God." - Jesus

   Even the corrupt bankers and politicians who are bringing down civilization are our erring brothers. If we "burn them at the stake", they can make no repentance of value to the planet, but if we are more merciful, perhaps many of them will reform, and being capable people who know the problems from within, they will be glad to help devise effective systems to counter the growth of such problems in the future.

---

How to stop the Peace River Site C Dam

   The best way to do something positive is to personally reduce your own grid energy consumption. If your dwelling has no other major waste of power, LED lighting will reduce the bill significantly. With the present cost of LED lights, that may seem like more money than it's worth, but if everyone in BC did it, we'd probably save substantially more energy than Site C is to produce for far less money. If the available bulbs aren't bright enough, a "Y" adapter lets you put two "bulbs" in one socket, space permitting. And of course, I'll happily sell my brighter LED light fixtures if anyone asks. (The yellowish 800 lumen Phillips at Home Depot for 30$ are the brightest LED "bulbs" I've seen locally. They were 20$ with a BC Hydro rebate for a while.)
   One person said he got an electric car and also put in LED lighting, and his electricity bill went down - the LEDs evidently save more than the car uses.

   The next option is to produce energy yourself: install solar panels or other green energy source, and or solar collectors for hot water. Our often overcast west coast isn't the best place for PV, but wide adoption would again reduce grid consumption more than Site C will increase production.
   And a small grid tie inverter for solar panels is evidently now affordable, if not economic strictly in dollar payback terms. (I must look into this - seems to me I was told you can get an inverter that's on or off grid, so it can switched to power a separate outlet(s) during a power failure.) With that and BC Hydro's new 'smart meters', I think it should be pretty simple to put power out to the grid to reduce your bill - or even get paid.
   Perhaps I should look into that as an alternative to the hot water tank "dump load" idea.

   Of course, these things can only work if lots of people do it, and it seems a shame so little of that 8 billion dollars for Site C - around 2000$ per every BC citizen - has been put into incentives to help people accomplish this. But every bit helps, and if starting now doesn't stop Site C, it might head off "Site D" or other megaproject.



Electric Hubcap Motor System

Improved Outboard from Scratch Design (forget Honda conversion)

   In considering how to fit the motor under the hood of the Honda outboard, it occurred to me to mount it at an angle and put in a U-joint... one from a 1/2" socket wrench set.
   Then on the 3rd, it occurred to me that instead of having a gear at the foot of the outboard, 2 or 3 or 4 U-joints in a string could make the 90º bend to the propeller shaft. This assembly, with no gears or pulleys, could make for the narrowest outboard foot ever. In fact, perhaps there need be no foot per se except a small bulge where the prop shaft comes out, for the seal. The leg would simply end just below the prop with a skeg.

  This started to make doing the "outboard from scratch" sound easier than trying to fit the motor into the Honda... and it should make a better outboard motor, eliminating the unfavorable gear reduction at the foot of gas outboards, probably with improved efficiency. Perhaps doing the Honda would be less productive than forging ahead and making this new design, which, once finished, can be produced. Since I plan to do an outboard from scratch sometime anyway, eliminating the Honda 'one-off' actually reduces the extent of the outboard projects overall.

   Once I started thinking about it, by the 4th design details started coming clearer. A short piece of 12" culvert pipe would (just) fit over the Hubcap motor for a housing. Ventilation air would come in the front at the top, and exit out the bottom near the front, which would be inboard from the transom. (A splash guard around the outflow might still be a good idea.) A broad slot for intake air might also be the wiring entry, allowing the heavy wires to twist inside for steering, rather than moving a long way side to side where they entered at the front of the rim.
   At the top of the leg, a toilet flange I bought for an LED lamp base would glue into the leg and make a good flat seat for the base of the motor compartment, connecting it solidly to the leg.
   If the drive shaft into the leg was made to drop into the bottom end rather than affixed, the prop shaft assembly could be lowered diagonally into the leg and then straightened as the shaft poked out the hole, which could be a screw-on pipe fitting with the shaft seal. Then the seal would be screwed on and the shaft would be inserted from above.
   The bottom of the leg would simply be glued shut (except for a threaded in replaceable prop shaft seal/fitting), reducing the chances of leaks. Oil for the lower unit could be poured in from the top or a couple of screws could go through the wall in the traditional manner.
   The transom mounting bracket details were still fuzzy. Potentially the round top end of the leg could simply twist inside something of slightly large diameter. Or stainless steel clamps around the pipe could hold a hinge pin at the front. Either way, the mount would still need to pivot up to lift the leg out of the water, presumably on a pin at or above transom level. And there should be a 'straight ahead' latch for rudder steering installations, and a catch for reverse to prevent the leg rising up. Another thought was that the farther forward the pivot was, the less the wiring would need to move for steering. I'll probably opt for the front pin.
   Perhaps the motor controller could optionally mount on the front side of the transom mount. Optionally because that wouldn't be the best for vessels using an outboard bracket - the controller should be within the craft away from waves and spray.

   Something that had been concerning me was that surely I'd never get a long enough piece of PVC pipe in the oven to soften and bend it. But when I measured against my boat, I found it only needed to be 20" long. The oven would take 21-22" straight, and perhaps a bit longer diagonally. Only the lower end gets bent to the streamlined 'teardrop' profile, since the top is out of the water and also it has to mate with the round ABS toilet flange. Furthermore, these tubes can be extended with another piece having a flange. If I only bolted the top to the leg instead of gluing it, extension to make it a "long shaft" would require only another (flanged) piece of PVC pipe and a longer driveshaft - common 1/2" square steel rod.

   The Hubcap motor for the top end is a given, so the first step in all this, I think, is to create the 'foot' mechanism holding the prop shaft, bearings, U-joints, and the socket for the vertical driveshaft. The size and shape of that unit will determine much of the lower end geometry.

   On the 6th I put the outer pieces together in a 'mock-up'. Imagining a domed cap to shed water, the wide, round top with the 4" 'stem' in the center suggested a name: the Mushroom Outboard.

   Also on that day, someone who didn't think highly of the U-joints idea mentioned looking up "right angle drives". Later "homokinetic drives" were mentioned. Amongst many ads and info for beveled helical gears, worm drives, and couplings for misaligned straight shafts, I found this, the "Almond" shaft coupling:

Taken from Wm. Griswold Smith's "Engineering Kinematics"1930. The drive shaft ends keyed to a ball joint with integral counterweight. [The ball joint is similar to that of a rear sway bar end link] A pin passes through the ball and into the 'trunk' of a "T" shaped sleeve whose cross bar slides vertically on a fixed post. The visible "T" actually has a 2nd "trunk" at a right angle to the 1st [i.e., on the 'Z'axis ] which connects to the pin of the output shaft. The motion of the pins is helical and reciprocal. The efficiency is claimed to be 90-93%, [i.e., better than bevel gearing]


   The description and diagram seemed clear as mud, so I did a search on the specific name, and came up with some you-tube videos showing the 'almond' and a couple of other types of gearless right-angle shaft direction changers.

   I still thought the U-joint looked the most promising, but the discussion list was skeptical. So I made a little test, with a bearing on the input drive shaft (1/2" square, black), clamped down, and a 5/8" center pulley "bearing" on the 5/8" propeller shaft (bolt).
   I simply held the pulley and the prop shaft with one hand while I turned the drive shaft with the other. If I tried to angle it more than 90º, eg 110º, the torque to turn it got noticably "lumpy". But at 90º, it felt pretty smooth, even when I put some resistance on the prop shaft.

   So I think two U-joints are both the best and the simplest idea. If the socket set ones wear out too rapidly, I'll try to make something better along the same lines. (I can visualize an 'ideal'. In essence similar, but the center would be a single piece instead of two pieces pushed together, and the pins would be beefed up and in line, perhaps with bronze bushings. But I'd rather not try making it unless I have to.)

   Saying it seemed to work well didn't convince everyone either. A working outboard might do it, but I'm not so sure - opinion was pretty averse.

   On June 9th, I thought of a good way to put it together: in a "sandwich" of aluminum plate bread. The bearings would sit upright in rectangular grooves or holes in the the aluminum, like car tires in potholes. When the two pieces were bolted together with a couple of rectangular pieces between to hold them straight, the bearings would be held rigidly in place.
   This proved more difficult than expected because I switched from ball bearings to sintered bronze bushings, and some of the parts had a greater diameter than the bushings.

   Then I realized I could eliminate one of the moving parts and make it more solid by making the prop shaft into the final U-joint segment. (And there was no point continuing with the housing without having a final shaft configuration.) This needed a stainless steel pipe of the right inside dimension to slip over the bolt (whose hex head was ground down to an indented rectangle), cut to end in two "arms" as the end piece of the U-join. (In fact... all the pieces could be replaced by 1/2" square rod and other off the shelf stuff.)
   While I was working on that, my angle grinder's right angle drive gear broke, with whole gear teeth going through the remains of the drive gear. And this wasn't the first angle grinder whose gears had failed. Hah! A beveled gears right angle drive has its own share of potential problems! I took spare pieces from previous angle grinders to try and make a "new" one, but immediately had the same problem. The next day I bought a new and somewhat more costly angle grinder.
   When I got this new U-joint arrangement far enough along to try it, it seemed to turn quite smoothly. However, if the center socket connection was uncoupled and one piece was turned 90º and then they were recoupled, it didn't work right. As expected, the unaligned cross pins had to be set to cancel each other between the two sets, not reinforce.

Sprint car conversion

   The transmission having been mounted, the linkage between the shift lever cable and the torque converter slippage control rope (bearing no particular positional relationship to each other) were connected via a small rope and two pulleys, as described below.
   Once a motor, controller and batteries are installed the car should be ready to test drive.

New Motor Drill Templates

    At first I used a calculator to calculate X, Y drill co-ordinates from rotor angles and radii. This grew thin after about the second time I modified the rotor design. Then it occurred to me to use a spreadsheet, and to cut and paste the numbers into the G-code drill program.
   This month I played around with a CAD program, LibreCad, which made 'standard' ".DXF" files. I did the design after a while, but then I had little luck with "DXF to G-Code" converters. Then I simply entered the text of the main body of the G-code into spreadsheet cells appropriately interspersed with the co-ordinate calculations, then just cut and pasted it into the program file, eliminating most of the grunt work. At last, a way to simplify it!
   On the 29th I finally got the stator plate drill template worked out, drilled it, and drilled the holes in the waiting motor parts. Using the template and a hand drill is easier than setting up the CNC machine each time a rotor or two is to be drilled. It also generally gets the holes better aligned, since the line-up of template and part is easy to see before holes are drilled, instead of after.



Planetary Gear Torque Converter Project

Planetary Gear 'Torque Converters' are already in use(!)

   It seems that Toyota Prius hybrid cars, and drive systems from another company, already use planetary gears effectively as torque converters. In both cases, electric motors or generators are being used to control the slip - or instead, variable forward drive - of the third element, in ways that aren't very clear to a casual glance.
(http://prius.ecrostech.com/original/Understanding/ContinuouslyVariableTransmission.htm [2001]) And it seems the GM Volt uses a planetary gear to connect two motors to the wheels, each running at half speed above a certain vehicle speed, to limit RPMs to the 3000's range instead of 6000's.

   Although the Prius has been around for over a decade, I've only been hearing that "2012 hybrid cars are using CVT's" in recent months. Even then, the term "CVT" instead of "torque converter" made me think of split pulleys and steel drive belts per typical past CVT's. The difference in terminology kept me from checking very hard when I didn't readily find any info on the web.
   So it would seem my big planetary gear "Eureka!" is a reinvention of something already invented. At least it validates that the operating principle is sound - it's in use. And sure enough, the Prius's engine is said to be only about 70% of the size it would be if the car had step gears, also validating my "2/3 the power" or "half again better" estimate.

   I wish I'd known about these systems 3 years ago when I started the torque converter project. It could have saved much of that time period - assuming I'd been able to wrap my head around the seemingly complex implementations to understand the working principles. It seems surprising that little excitement ever seemed to be aroused about such a breakthrough technology, and that it isn't finding its way into all cars... except maybe that improved fuel performance probably may still not be what the oil barons want... or maybe it's still not understood that it could be used with any motive power: The more complex idea of driving two of the three gears has distracted from the simpler one of simply allowing one gear to slip - just set up the ratios accordingly.

   My mechanical brake or clutch idea for controlling the slip still appears to be new, or at least a new implementation. (...although at this point I wouldn't be surprised to learn something like it had been done a century ago.) If it proves to work well - that is, that the driver can control it easily and smoothly - then it's surely the simplest way to do it.

"Clutch" tension linkage installation

   Something that had been puzzling me for a couple of months was how to get the gearshift cable to line up with the friction rope around the V-belt pulley. The positions and angles were all wrong, and the cable certainly wasn't very flexible. Towards the end of the month I had the thought that by clamping a small rope between the big rope and the shift cable, and installing some strategic small rope pulleys, the positions and directions of pull could be altered as convenient. Having a plan is so much better than not that I got onto the job.
   I came up with an arrangement for the pulley end. Then I looked for my old stainless steel boat hardware including some pulleys that should do the job... and realized I must have given it away a few years ago when I thought I had no use for it. Sigh!

   I also started to think that a foot pedal clutch might be better than the hand operated "parking brake ratchet" idea. It would be like the traditional manual clutch pedal, except that it would be engaged and modulated by the foot for longer periods as the car gets moving. But there'd be no gears to shift, so it was "hands free" and it might actually be easier. I decided to see about getting a clutch pedal and cable next time I was near an auto wreckers, since my automatic car didn't have them. On the 23rd I went there at 1:30 PM, only to find they close at 1 PM on Saturdays. Sigh!

   By Monday I had changed my mind again and decided to hook up the gearshift lever as originally planned. It has the advantage that it can be set to some intermediate tension and left there, which might be best for low speed travel. I started to consider that the clutch idea might prove to be a nuisance.
   I bought a couple of pulleys and clamps to join the ropes and shift cable. On the 26th, after some perplexing but imaginary problems rectified by reinstalling the part of the cable inside the car, the shift cable came out to near its original position under the hood (gosh!), and I used its original fastening plate, slightly modified, to fasten it to the new 'transmission' box.
   I put one pulley under the V-belt pulley on the 'transmission' frame base. It seemed the pulley to the shift cable would have to be mounted near the left headlight. This seemed fine and I mounted a pulley there. Then I remembered that the frame of the car wasn't rigid to the shock mounted transmission and motor assembly, so the rope would tighten and loosen when going over bumps, jerking the motor and mechanism. All the pulleys had to mount on the assembly. The stiff cable stuck out past the assembly, so I'd have to make a big tripod out of square steel tube or angle iron to have a place beyond it to anchor the pulley to the cable - sigh!
   I set to it and made the main piece of .5" x 1" square tube. Then a support piece of 3/16" x .5" solid steel, twisted and bent to fit, that was virtually in line with the direction the rope would pull. I decided that was sufficient without a third leg unless proven otherwise.

   Of the various alternatives for how to make the slipping gear mechanism work, I'm starting to think this may in fact be the best of any of the simple ones, in spite of the manual tensioning lever. (If it needs a new 2' rope every 6, 12 or 24 months, so be it.) The second motor-generator system, under computer control, might be superior, but at a much higher cost and with considerable development needed.



Solar Electricity Project

Wooden Collector Mountings

   There was an aluminum frame mounting system that HES evidently makes. Evidently it's a good one. I decided to save the money and do a wooden mounting system. The four panels were to mount beside each other in a single row. 14 foot 2"x4"s bolted to the steep roof would be long enough. With the top one, I planned the collectors to slightly overhang the peak of the roof to keep much of the water from going under. The bottom one would give a bit of support for traversing the steep roof while putting them up.
   I didn't want to have to cross over any of the panels to their far side during installation. The first one would have a 40 foot drop inches from the far side. The rest would all have the previous mounted panel in the way. So I came up with a hooking system by which the "L" shaped panel edges would be swiveled into place, "clipping" them on at the top corners and on the far side near the bottom, and a lag bolt on an outward facing "L" bracket across from that would fasten the fourth corner.

Solar Panel cross section:
_________________________
|_                                       _|  <-- inward "L" aluminum angle edges

   Thus the panel could be maneuvered and twisted into place and then bolted down at the bottom near corner, with a single lag bolt and without having to cross the roof to the other side of the panel. I didn't look at the aluminum bracket mounting system, but I bet you couldn't do that with it! I could be wrong. The 2x4's and their associated wooden "clips" were put together, and everything including the wiring was tested for fit on the ground to give the best chance that everything would go smoothly on the roof.

Hot Water Collector (What does this have to do with electricity?)

   I figured if I was going to have a hot water preheater tank, and since the shingles are wearing out and coming up just along an edge of my roof where the wind evidently was catching them, I should put up a solar hot water collector to cover that edge. (in spite of some afternoon shade from trees.) One thought was to simply have fat plastic pipes on the roof that would hold the hot water themselves. No pump would be needed. The other idea would be to have an unpressurized drain-down system that would pump water through a pipe in the preheater tank. That did need a pump, but solved winter water freezing problems. Either way, PVC pipes, not available in 1980 when I made my previous solar hot water collector system, would be cheaper and easier to install than copper.
   I went to a plumbing store to check out options and prices, and they suggested Van Isle Water Services. They had ready-made collectors of rubber mat with small tubes molded into it "for swimming pools". I had first heard of this in the early 1980s or so. There were two brands. One cost just 245$ for a kit of two 2' x 10' collectors, plastic rather than rubber. (I had only been planning ~18" x 10'.) It didn't fit any vision of what I'd been thinking of, but as I drove home it dawned on me that it was the ideal choice, and I bought it the next day. They'd make a lot of hot water, and the plastic mats should make good roofing! The solar hot water would save substantial electricity for a fraction of the cost of equivalent solar PV panels... and help put off reroofing, hopefully by a decade.

   It seemed a natural to find a 12 or 24 volt pump and power it from the DC Grid Tie system. To control the pump, a 'differential thermostat' would use two temperature sensors to see if the collector was warmer than the tank, at least by a degree or two, with the outdoor air above freezing. I made one of these in about 1995 for someone else's solar water system. (LM339, AD590's or LM335's) Whatever collection was available could continue even in winter, whether rarely or often.
   And I'd have another useful module that can be added to the DC Grid Tie system!
   I considered garden and marine supply DC pumps, until the people pointed out that most of these weren't made for continuous operation, were less energy efficient than AC, and were all made for cold water, not hot. The higher flow rate and pressure of the AC pump was also desirable, and to top it off, the one I found had three settings to find the best speed and flow after installation. I could have found a separate DHW pump and used my DC lawnmower motor with it. But the quiet AC pump should last many years with no maintenance. The differential temperature unit would have to be just a switch to activate a solid state relay (SSR ...or maybe could include a power MOSFET for 12 VDC pumps regardless.)

   An inverter can still run the pump off the DC unit if desired, but I admit I'm becoming distressed by the number of simple things I can't get for 12 or 24 volts, or which cost far more or don't work as well. Such factors mitigate against adoption of low voltage DC home systems and solar systems.



Turquoise Battery Project

   I'm shortening my self made terms 'positrode' (positive electrode) and 'negatrode' (negative electrode) to 'posode' and 'negode'. I think they have a better chance of catching on to replace the unintuitive and ambiguous terms 'anode' and 'cathode', which reverse in meaning depending on the direction of current flow.

3D Printers for Plastic Parts Production

   Long ago when the first laser printers came out, I noticed that they laid on so much PVC(?) toner that the printing could be felt with the fingers. Others evidently noticed this too and took it to another level: printing on top of printing, layer on layer, could make a solid 3D object.

   After visiting Camosun College's VICAMP prototyping facility and seeing their equipment in May, I started to consider that 3D-printing of ABS plastic would be uniquely suitable for making perforated plastic pocket electrodes, because they could simply be made with the perforations built in, instead of having to burn or punch them out afterwards. In looking up these rather new (and various) 'additive machining' technologies on Wikipedia, I found this insight about their general application:

"Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did....Just as nobody could have predicted the impact of the steam engine in 1750—or the printing press in 1450, or the transistor in 1950—it is impossible to foresee the long-term impact of 3D printing. But the technology is coming, and it is likely to disrupt every field it touches."

—The Economist, in a February 10, 2011 leader

   The question was means. I figured I wasn't going to find such a micro-factory on Used Victoria or eBay for an affordable price. But as I read on, to my surprise I found 3 digit prices mentioned for kits instead of 5 or 6 digit, so I started checking them out. Sure enough, they were affordable. Their revolutionary nature has had a huge impact on the machines themselves: their custom formed plastic parts are made on other 3D printers, so they're easy to reproduce in small quantities. If they needed injection molds, we'd still be waiting for them to drop under that 5 digit price barrier. The first manufactured item "disrupted" by 3D printers is 3D printers!
   Instead, an open source 3D printer revolution was started by a developer in London about 2007, and it started catching on.


reprap mendel 3D ABS/PLA plastic extruder-printer

www.reprap.org/wiki/: "RepRap was the first of the low-cost 3D printers, and the RepRap Project started the open-source 3D printer revolution."

   I also read about a plastic I hadn't heard of before, "PLA" or "Poly Lactic Acid", made from plant material such as corn starch, tapioca or sugar cane instead of petroleum products. The machines I'm interested in can use either ABS or PLA.

   SO! Forget injection molds entirely: the plastic parts for my version of the Turquoise Battery can be made with 3D printing technology. The writer in The Economist was right - certain things that were hard until now have suddenly become a LOT easier. Battery making may be the second thing revolutionized by 3D printers.
   Regardless of chemistries, printing electrode containers and other battery parts will make homemade batteries practical for the first time. After all, a battery is just chemical powders, crammed into "+" and "-" housings, with some sort of current collectors connecting the chemicals and all immersed in or containing some sort of electrolyte. Cramming chemicals is simple - appropriate structures and current collectors to cram them into constitute the hard part.

   In fact, the thing will have other uses as well: for example, custom made LED light fixture bases for various styles of diffusers would simplify LED light construction and they could be made easy to screw into walls and ceilings without even removing the diffuser. For another example, anchors and mounts for various things like the terminal blocks in the motor controllers and in the "DC Grid Tie" units.

   On the 9th I ordered a complete kit for a somewhat smaller model, www.REPRAPpro.com/Huxley . It's expected to ship July 20th. Work area is 140 x 140 x 110 mm.


REPRAP Huxley as made in kit form by RepRapPro

   I seem to usually be in the next-to avant guarde in printer technology. Interestingly, The Huxley is similar in dollar price to the first mass market dot matix printer, the Epson MX-80 (1981?), and to my first color inkjet, the original Epson Stylus Color (1992?). And half the price of my first laser printer IBM4029, similar to original HP Laserjet (1993?) (My first color laser printer, the Samsung CLP-300, was much less than any of the others above - I must have been late getting in.) Back then, each dollar was worth substantially more than it is now, so in effect, 3D printing is the cheapest new printing technology yet - and look what it does!

   There were also additional recent designs: the Ultimaker (Holland) and the Solidoodle (USA). Ultimaker is evidently faster but costs more, and it looked like Solidoodle (cheapest... and pre assembled) isn't ready to ship yet.


3D printing can make parts that previously only injection molding could - and more.

Electrode Pockets from VICAMP


   Meanwhile, I had contacted VICAMP about making some ABS electrode pockets with their machine, both as potential alternative production and to get some soon instead of maybe by next fall. The REPRAPs have a heated table. The VICAMP machine keeps the part in an enclosed 'oven' space closer in temperature to where the plastic softens, which makes parts that stick together better and warp less. It can print polycarbonate and ?"ulton"? - similar to nylon) as well as ABS and no doubt PLA. (Polycarbonate and Nylon... I start thinking of planetary gear/torque converter parts!)
   I had had the idea of making the pockets lying down, in two halves to butt together and glue. (For that, the heated table should be sufficient.)

 ______
|         |
|_____|

   The VICAMP maker came up with a slightly more elaborate design where ideal alignment was assured:


First batch of open ended "boxes with lips" pockets from VICAMP.


pocket 'boxes' as assembled showing closed bottom end.
The mesh of the ones on the right seemed too coarse - the chemicals might come out.
Only the narrower one (@ 1/2" vs 3 @ 5/8") one on the left was stiff enough to consider using.

   From this design, I came up with the idea to have one half fitting over the other:

 ______
|         |
 |____|

   These would glue together along the 'verticals'. The sum width of the adjoining vertical walls could still be strong even when made narrower than the walls butted together or in the first 'box' form, wasting less plastic and adding less size and weight to the cell.

   A second batch of pockets all looked usable, altho several different patterns, wall thicknesses and internal thicknesses had been created. The thin ones looked almost like my text drawing above.

   I wrecked one of the boxes. I put too much methylene chloride on to glue the halves together, and some spread onto the mesh. The perforations in the mesh filled in, and simply touching the mesh while it was wetted broke it and left two jagged holes. This however led to the realization that the slightly porous printed parts, to use them for cases and pressure caps, could be sealed simply by a quick application of, or a dunking in, methylene chloride.
   I think the cases can be printed square "U" shaped bottom and ends, while the wide sides can simply be pieces of flat ABS sheet glued to the "U"s. The fairly precise control of dimensions printing the "U" and the matching glue-on lid will make the cases relatively simple to fabricate and assemble.
   Or the whole open top case might be printed as a unit. However if it needs to be saturated with methylene chloride to seal it, it might not be as much easier as expectable. This might still be a good place for an injection mold.

Next Mn Negode

   Having obtained pockets for electrodes, zinc collector plates, and manganese carbonate, I decided to to make the manganese monoxide with heat:
MnCO3 → MnO + CO2 - at 200-260ºC.
   As an aside, another way to convert the carbonate would be by making the electrode and soaking it in [dangerous] NaOH or KOH. This exchange reaction makes Mn(OH)2 + Na (or K) CO3 - a contaminated electrolyte to dispose of. (as garden fertilizer?) The heat method is preferable IMHO if it does an acceptable job.

   The surprisingly low temperature can be had in a kitchen oven set to 450ºF or 230ºC. The one problem with it is that without an inert gas facility, the MnO readily absorbs oxygen from the air to form Mn3O4 or Mn2O3. That's at least less oxidized than MnO2, but I could derive it from MnO2 with a higher temperature. I put it in a crucible and put aluminum foil over the top. Perhaps the CO2 would drive the oxygen out of the crucible?

   I put 100g of MnCO3 [valence II] in the crucible. The results should be indicated both by the color and the weight after the CO2 is driven off:
MnCO3 - [II] light pink - 100g
MnO - [II] green or "dark colored" - 62g
Mn(OH)2 - [II] white - 77g
Mn3O4 - [2.33] red or brown - 66g
Mn2O3 - [III] dark brown or black - 69g
MnO2 - [IV] black - 76g

   Short duration heating in the kiln (on the 17th, 15 minutes?) with the powder in the crucible and aluminum foil over the top resulted in 97 grams with brownish powder around the outside, still pink in most areas.
   I decided to put it in a small stainless pot in the oven at 425ºF/220ºC, still with aluminum over the top, for 90 minutes. It looked about the same and weighed 97 grams.
   I tried again with the oven at 460ºF. This time, the whole mix turned a medium-light brown - perhaps about right for Mn3O4. But it still weighed 96.4 grams. Surely it should at least drop below 70!
   Next try was at the oven's highest setting, 500ºF/260ºC. 260ºC is where it's supposed to start forming Mn3O4 or Mn2O3 instead of stopping at MnO at all. But I'm beginning to think the oven temperature is a little below the dial setting, at least up near the high end. But the weight was still 95 grams.
   On the 19th I tried putting it in the new crucible and torching it. (It was so windy on the 18th I waited a day.) The top glowed red, but I realized it wasn't heating very deep in. So I dumped it out, aimed the torch into the crucible, and started sprinkling the powder in with a teaspoon. The torch not only heated the crucible, but also the powder as it fell past the flame. This time the powder, still medium brown, was down to 85 grams. I repeated the process and got about 72. I repeated it a third time and it was down to 59 grams. I figure probably about 2-4 grams was lost in all the handling and sprinkling. However, in the reducing propane flame and seeing the low end range of the product weight, I figure it probably formed either MnO or Mn3O4, or some of each, rather than higher oxides. Or it may in fact even have formed some metallic Mn. To my eyes it's medium-dark brown with no hint of green, but I'll call it a success. (Would it turn white in water, converting from MnO to Mn(OH)2)? Hmm... not in clear water.) I was surprised that in all this torching, the torch flame didn't seem to be blowing any notable amount of powder away from or out of the crucible.

   If I'm going to torch it anyway, I might as well be starting with MnO2, which should also reduce to MnO in the torch flame. With either substance, if this is how it's to be done, I should set up a stand for the torch and some sort of funnel pouring system that'll automatically drop out an 'hourglass' sort of fine sprinkle of powder. Without 'clumps' of powder going by it'll probably just take a single pass through the flame.

With that at last ready to go (on the 20th), the negode mix could be formulated:

MnO active chemical - 80% (32g / 32.6)
Zn conductivity enhancer - 20% (8g / 9.4)
Sb2S3 hydrogen overvoltage raiser - 1% (.4g)

   For the electrode pocket, I selected the (only) 4.5mm thick one from batch 2, with .042" (1.05mm) thick faces, 4.65 grams. It was quite stiff with little flex. The 'lid' sides were all the same shape, but I forgot there were a couple of non-perforated ones until after I'd glued it on. Nevertheless, it seemed to be 'microporous' (evidently typical of printed ABS parts), which is probably good enough -- maybe it's even better, saving the trouble of putting in a separator sheet or spacers. I can hardly wait to get my own 3D printer to try out variations.

   I had cut the zinc current collector (2.25g) about the end of May; now I made a 2mm thick aluminum spacer to put in while the first side was filled. The next day I made the mix, wetted it, and stuffed it in. I had no particular system set up, and it must have taken an hour of dropping a bit of mix on the zinc plate and stuffing it in with a 'plunger', ad infinitum, then repeated for side two. The zinc current collector 'tab' was bent a few times and the tip broke off in all the stresses. The mixture, with no binding agents, was loose and not amenable to good compaction. It mushed out around the plunger, even tho it wasn't very wet. Zinc makes initially very fragile electrodes; this seemed as bad or worse, and worse than the sintered one.

   Starting with 10 grams, I had less than 2.5 remaining, so about 7.5 must have gone in. The MnO was about 79% of that, so 5.9g of MnO. The "O" dilutes pure Mn's .975 AH/g, yielding about 4.4 AH theoretically. If the bulk of that proves accessible for discharge, it should be quite good, but for production I'd like to see more Mn compound and less extraneous structure if possible.
   I put the electrode into the Changhong cell with its nickel electodes, with a piece of watercolor paper folded over it. The leed barely stuck through the top to make connection to, and that by pulling it up a bit. Initial voltage was 1.7 something. After a few hours charging at ~50mA, it sat at 1.84.
   Charging voltage, instead of rising, started at 1.92 and dropped to 1.905, and stayed around that level some hours even as the off-charge voltage rose... then it dropped further to 1.895 with an off-charge voltage of 1.85. Hopefully, that meant that the electrode was building current bridges and oxide was becoming more conductive Mn metal.
   With a 2.2 ohm load, output dropped below about 1.2 volts; 1.25 volts after a few hours; then almost 1.3 when the day was done.
   The next morning, it had improved to 1.87V open circuit and 1.4V with the load. But I opened the cell and found an 'erupted' pile of light gray material had oozed out of the electrode. Well, it made sense that Mn(OH)2 should take up more room than MnO, and white Mn(OH)2 would explain the light color. Perhaps I shouldn't compact it much at all, and just let this swelling do its work? I scraped it off and let it fall into the cell. I'd have liked to look at the whole electrode to see if the sides were bulging or if it was also oozing out the perforations, but that would have meant disrupting everything, and I also dislike working with caustic KOH, so I left it for later, when I would also change the electrolyte, since it might have a fair bit of carbonate in it by now from any leftover MnCO3, plus the sludge on the bottom. If any was oozing out, the paper I had put in should prevent shorts. The nickel electrode was bubbling (oxygen) since it was already charged and the charging current continued. The Mn side only bubbled a bit.
   After another couple of hours, the charging voltage started going up, and I had to reduce the current to 50mA again. It seemed much too soon. Was the zinc plate disintegrating? I had pulled it out a bit when I inspected, and it came up disturbingly easily through chemicals it was supposed to be in minute contact with. Would this electrode deteriorate and become useless like so many others I'd made? No load voltage was up to 1.87, and a 2.2Ω load test delivered above 1.5 volts -- but dropped off with passing seconds, indicating poor connections through the electrode. Probably disturbing the current collector upset things?
   1.88 volts seemed too high to be zinc [+.49 - -1.28 = 1.77V], but not really there yet for manganese [+.49 - -1.56 = 2.05V].
   On the 23rd I opened the case and removed the electrodes. More mix had evidently oozed out the top around the edges of the pieces of plastic I inserted to prevent this, and seemingly also through the tiny perforations - but only on the side with the intended perforations. The 'microporous' side was clean. Evidently, the powders being very fine, microporous is the way to go - and a good fitting glue-on lid would be a definite asset. In fact, it seems to me Alkaline Storage Batteries mentions a special Ni(OH)2 mix for flooded pocket electrode cells - I bet it's a specially coarse mix to minimize oozing. And they do anyway. They have to have it rinsed off before final assembly. Being able to print very, very fine perforation - more like 'pores' - will be a definite 3D printer technique asset over punching holes in solid pieces.
   After rinsing the electrodes and knocking the stuff off, I put the battery back together. (I didn't change the electrolyte.)

   Obviously this not so well compacted 'loose fill' electrode was nothing like as conductive as the previous sintered electrode, but it did gradually improve over the hours as it charged. I'll be thinking of how to do this all better. The 'microporous' plastic side may (just possibly) have limited ion flow to that side.
   Perhaps a good way to make Mn(OH)2 would be electrical reduction of MnO2 - to discharge it as a negative battery electrode reaction, but stopping when it hit -.15 volts instead of trying to charge it to -1.56. The Mn(OH)2 at least shouldn't expand after the electrode is assembled.

   I finally woke up to the fact that the 1.8 volts that seems to be as high as wants to stay charged to is roughly the voltage of NiZn, not NiMn. Reaching 1.9 volts can be done, but the Mn doesn't stay charged and it drops back to 1.8.
   At this point, I began to think that Mn negodes don't work in KOH electrolyte because the voltage (-1.56) is too high even with antimony sulfide added. They do seem to work in my 'moderately alkaline' cells, perhaps because the voltage decreases more rapidly than the alkalinity to -1.18V. (Zinc drops to under a volt in these conditions. But NiOOH and KMnO4 both go up faster with falling pH, so the overall voltage is higher.)

   I also keep looking at that zinc pourbaix diagram that shows no soluble state between pH 8 and 13 - the desired alkalinity range. Accoring to theory, that should mean zinc won't form dendrites at those pHes, in which case it would make a very good negode material producing roughly 2 volts open circuit. I'm not convinced it would actually work that way and make very long life electrodes... but it looks like it on the chart, so it might.

   That the Ni-Mn/KOH cell won't charge Mn to metal meant the next step should be to make a complete Mn-Mn/KCl cell to repeat for verification the successful chemical results of February, but with the new current collectors/terminal leeds to hopefully get better conductivity.

 
  I used the KMnO4 posode from April (with one pocket nibbled off and tiewraps to hold it closed) and the Mn negode pulled from the Changhong cell (still oozing stuff). Another bit of the zinc terminal tab broke off and I had to make do with such a short length that even coming close to sealing the cell looked problematic. I did what I could.
   Conductivity was very poor and the water turned purple (sigh!), but sure enough, even with only 8mA charging current, in KCl it immediately started charging to well over 2 volts, too high to be accounted for by the permanganate-zinc (~+.95 - ~-1 = 1.95). Only permanganate-manganese (~+.95 - -1.18 = 2.13) would explain the high voltage. After a while it hit 2.25 volts. There was still some self discharge, whereas it seems to me that in February I had pretty much eliminated it.
   Then it occurred to me that with the cell being poorly sealed, oxygen would get in. If oxygen would discharge MnO to Mn3O4, it would surely discharge wet Mn to MnO or Mn(OH)2 in spite of the antimony. In fact, it discharges cadmium and metal hydride - that fact is used to keep dry cells from bursting on overcharging or too rapid charge. That probably explains all residual self discharge. It would seem that alkaline cells must be essentially sealed to hold their charge, with of course the high pressure release.

   Evidently I've been wasting my time thinking that Changhong could make the chemistry work with their existing flooded KOH alkaline cell production line. It seems to need the carbon parts, salt electrolyte... and likely a somewhat better sealed case than theirs. Again it seems fortuitous that somehow I didn't convince them to try it out. When I can send them a finished, working battery I'll do that and see what they think.

   It's probably time to set the battery project aside until August or September when the 3D printer arrives and is assembled (except maybe for a bit of preliminary 3D electrode pocket computer modeling). Then I'll be able to easily do things that have proven difficult - even problematic - so far: ideal plastic pockets, and 'slight-pressure' cells with caps that don't leak... or even cells that don't leak.

Conductive perforated plastic electrode pockets!

   Since I had ordered the 3D printer, I started looking into sources of ABS plastic. I was informed there was a conductive ABS printing filament! I explained that it would have to be conductive carbon or graphite based for the positive electrodes, or conductive zinc based for the negatives, and that nothing else would work.
   It turned out the conductivity was based on carbon fiber! This could revolutionize the position. Instead of grafpoxying a thin, narrow 'sheet' of carbon fiber for each electrode and sticking it into the middle, then having to compact powders on each side of each one separately, the electrode can be printed as above but with a connection tab to stick up through the case. Stuffing would be one simpler operation instead of two more fiddly ones. In fact, a whole set of pockets forming a plate with a tab could all be printed at once.
   It would all depend on how conductive the ABS really is -- or could be made to be with toluene, osmium/aldehyde, grafpoxy or whatever. Of course I put some on the order - it was just becoming available, a new product. But it would probably arrive before the printer.

   In addition, the person said he would consider trying to make conductive zinc ABS filament as well. This doubles the excitement! Certainly one couldn't pull the terminal leed and disturb the connections if the basket was the current collector. 3D printing, with conductive printing filaments of the exact formulations required, might just solve nearly all the battery production problems at a stroke! However, I might have to pay something up front as an inducement, and of course the endeavor might not successfully produce a practical material.

   The big advantages would be:
* The pockets would be printed automatically, sizes, shapes and material as desired. This alone saves a heck of a lot of work. (If printing 3D parts is too slow for production needs... get or make some more printers!)
* The printed pockets would have attached printed terminal leeds exactly sized and positioned for the holes in the lid of the cell, with all the pieces liquifyable by methylene chloride. The cell would thus be much simpler to assemble and to seal.
* The mass of these non-reacting 'extraneous supporting structures' that reduce the energy density of the electrodes could (I'm sure) be reduced somewhat.
* The electrodes would be easier to fill and compact the powders into -- again saving a lot of labor.

   Later he said that for all the hype, he had been unable to get the conductive ABS from the supplier to make into filament. Now I'm trying to think of other ways of accomplishing the same sort of thing.

2-piece pressure caps?

   I had considered the pressure cap a being something that would screw into the lid of the cell. As such, it would need a bottom piece, a threaded-on top piece, and a 'plunger' or other shape of sealing piece. But the bottom piece could be printed right into the lid of the cell as part of the lid. The top piece would be unscrewed for access to the cell. The main disadvantage I can think of offhand would be that the plunger would need a much larger sealing seat to give a sufficient hole for access.

Mn: a really economical, green battery chemical

Surprisingly I read:
"Together with manganese sulfate, MnO is a component of fertilizer and feed additives. Many thousands of tons are consumed annually for this purpose."
Surprisingly... because how - and why - do they keep MnO from oxidizing to a higher oxide when it seems so hard to prevent? I suspect a glitch in the writing here somewhere. Anyway, such widespread, and agricultural, uses of manganese compounds indicate both their economical and environmentally friendly character.



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Victoria BC