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  How to Make Economical,Green, High-Energy Batteries Small Scale/DIY Battery Makingthe Turquoise Battery Project PRELIMINARY EDITION 4by Craig Carmichael, March 11th 2012  TurquoiseEnergy.com DISCLAIMER: This information is provided freely and is in no instance or detail guaranteed as to accuracy or veracity. Anyuse made of the information is at the sole risk of the user. No liability will be accepted by the author. The author warns thereader that his highest formal chemical education is a 74% grade in Chemistry 30 in grade 12, in 1972.Note that preliminary editions are being written as research proceeds, and the text may not be consistent within itself: onestatement might say is expected to or should , while somewhere else, text written later may simply say this is how itworks , or perhaps mentions that it doesn't work , or simply omits further reference to an earlier idea that didn't work. ==>  Check the catalog at TurquoiseEnergy.com website for planned availability of custom battery making tools and partssuch as electrode compactors, plastic battery cases, current collector screens, and more. ==>  Check editions of TurquoiseEnergy.com/news/ later than the date of this document for newer information andprogress.Contents 1. Foreward and Backward2. Electrochemistry Overview  The water-based battery cell environment pH: acidity and alkalinity Battery Electrochemistry Electrode Substances - Nickel - Vanadium - Perchlorate - Manganese - Zinc - Current Collectors 3. Battery Construction Overview Electrodes OverviewBattery Layout(s)Chosen LayoutElectrode Binder glue Separators and Capacitors 4. Making the Case and Fittings CaseElectrode Current Collector Grills & Terminal Leeds 5. Making Perforated Plastic Pocket Electrode Enclosures Perforating the plasticForming the square cylinder    converted by Web2PDFConvert.com  End caps'Glue'/solvent 6. Making the Positrode  6.a Permanganate/Nickel Hydroxide Positrode 6.b Monel Positrode 6.c Vanadium Pentoxide Positrode 7. Making the Negatrode  7.a Zinc Negatrode 7.b Manganese Negatrode 8. The Electrode Separators9. Electrolyte and Cell Assembly10. Charging, Forming and Testing Initial Rest PeriodInitial chargeInitial cyclingTesting Specs 11. Appendices  A. Creating Unusual SubstancesB. Materials and Chemicals Supply SourcesC. Equipment & SuppliesD. Survey of Some Battery Electrode Materials 1. Foreward and Backward  In one sense, batteries are a well known technology, intellectual property of mankind. In another, theyare almost a lost art. Factories churn out inferior lead-acid cells and small cells for portable electronicdevices and cordless tools, but the employees are just workers. While the theory of operation and thechemical reactions aren't hard to undersatnd, there are a few important details needed for successfulconstruction that aren't mentioned anywhere in particular, certainly not all in one place, and very fewpeople know anything practical about battery design and construction. A great need has long existed for long lived, economical, high energy batteries for electric transport andoff-grid power. I decided to try my hand at creating some way to make some sort of batteries at home. I soon felt sure that some better chemistries, probably much better, than existing types could becreated, and potentially for lead-acid or throw away dry cell prices, or not so much more. This bookdescribes known and newly invented alkaline battery chemistries, and no less importantly, a design forDIY buildable batteries of any size, that I've come up with in a project spanning - as I write - over fouryears. Battery research and commercialization have been sidelined by human propensity to go with the flow ,to limit thoughts into narrow structured channels, good or (more often) inferior, and to extend that channelto the exclusion of wider possibilities, including superior ones. Thus for example, with large, higher-energyalkaline batteries having been killed commercially, and with the single-minded recognition that lithium isthe lightest atomic weight metal, most research today has been working on trying to develop betterlithium batteries, despite the cost and the complex problems of making lithium work well, and despite thefact that since patents on the best developments are acquired to suppress each development as it emergesto market stage, their work will dead-end the same way Ovshinsky's excellent nickel-metal hydrideelectric car batteries did. We trust this state of affairs won't continue for a second 100 years, but in themeantime, DIY battery making provides the rest of us a way to take matters into our own hands. Making 'normal' water based batteries is a rather involved but fascinating DIY project touching onseveral distinct specialties, and it creates a product truly valuable to civilization at this time. The process of learning and making will challenge and broaden your base of knowledge and abilities. converted by Web2PDFConvert.com   How was I to write this? Should it be just do this and do that and you'll have a battery, should Iprovide a little background, or should the reader be given all the gory details, the reasons and reasoningbehind the instructions? Knowledge is power! I'm telling all that I can think of to say. But I'm organizing itinto various sections so the reader can read as much or as little as desired - the basic instructions, a goodtheoretical overview, or complete detail. In other material, even the most basic information is lacking for neutral pH salt solution cells. Forexample, why is the positive electrode in a standard dry cell a conductive carbon rod instead of metal as inall other batteries? You'll dig long and deep and not find the simple answer: that every common metal willcorrode away in the positive electrode in salty electrolyte - including nickel, which sits inert in and enablesall the various KOH saturated alkaline cells. Only carbon or graphite works. (Note: nickelmanganate+epoxy mix might work) Obviously battery makers know this (or once did), but it took meover two years of corroded electrodes in every test cell to figure it out for myself, because no onementions it anywhere. (I put it on Wikipedia, but it appears to have been erased.) Much of the info herein has been acquired gradually, and often painfully, in my battery research over thepast 4 years. A tidbit of basic info is casually mentioned in one publication or another, most of whichassume the reader is well versed in the battery making arts - and few people are. For example, it was only after 2-1/2 years that I finally saw for the first time an actual figure for theamount of pressure used to compact a battery electrode into a briquette - for one type of electrode inone experiment. When I started, I wasn't even aware of the vital role of compaction, and after eventuallydeducing it indirectly from some material density specs, it took a another year to figure out a simple wayto get enough pressure. Likewise, it wasn't until February 2012 and four years of mysterious self-discharge problems that Iunderstood that the wires in the negative electrode had to have as high a hydrogen overvoltage as theelectrode substance itself. Anything goes for iron, cadmium or hydride, but few common things work witha higher voltage chemical - zinc or manganese. It has to be zinc or zinc alloy wire. (or silver.) My srcinal minimum battery goal was to copy proven and relatively economical NiMH EV batterychemistry, by the simplest techniques I could find or work out, and thus create a DIY means of makingbatteries. But I also started to think that coming into the field as a newcomer without formal training inthe field as to that's how it is , I might, in stumbling around, uncover overlooked information or ideasthat could lead to a better battery. That would have the additional advantage that being developed by me, freely and openly published byme, and designated by me as the inventor to be free technology, there would be no patent restrictions onit for vested interests to kill commercialization with. (And patents aside, it probably would have been verydifficult to make a decent hydride alloy.) I did indeed do a good bit of stumbling around in my ignorance, getting wild ideas and then seeing theflaws, and gradually learning many broad basics and fine details in no particular sequence. And I diduncover a few key overlooked things. I also developed useful DIY battery construction tools and techniques, such as a bolt-down electrodecompactor, and perforating rigid plastic sheets with a heavy sewing machine to make solid pocket electrodes. Finally I have been rather successful: nickel-manganese and similar batteries are in principleeconomical, green , and superior to what's on the market today, including being quite economical andhaving about the highest feasible energy density, perhaps on a par with lithium ion types. I picked thereacting substances out of a considerable number of possibilities because they seem to be the best. Thefact that they are also common and relatively economical is an excellent bonus. Unless otherwise specified, quantities given as a percentage, eg 1% antimony sulfide , mean percent byweight ( wt% ). Sometimes this is in addition to the otherwise complete chemicals. So if an electrode has65% nickel hydroxide and 35% graphite powder, and 1% Sb 2 S 3  is added , the total weight is 101%. I'm introducing here some new terminology - more accurately, two terms and a new spelling. Mostliterature uses the terms anode and cathode . The meaning of these terms is reversed when the batteryis charging from when it is discharging, and while there is a convention that anode refers to the negativeelectrode (while it is the positive terminal of a diode or a non-rechargeable battery), this is not universallyadhered to, and there is often confusion about what is meant - I often get mixed up myself. As electrodesare ubiquitous to the subject and a specific one is so often referred to, herein I will call them positrode and negatrode , which terms should be self explanatory. I also insist on spelling terminal wires as leeds to differentiate connections and wires from the metal lead , the guy in the lead , and at least a couple of other uses of the same four letter sequence, hoping not to lead anyone astray. converted by Web2PDFConvert.com  2. Electrochemistry Overview  The physical design and construction is more important to making a battery that works than theelectrochemistry. But the electrochemisty is the premiere part, the fascinating part, so it gets the firstchapter. I've tried to explain less common, specifically electrochemical terms herein, but the reader willunderstand the text better if he still remembers his high school chemistry. If you don't know what an ion or a sulfate are, just look them up on Wikipedia. If anyone asks, I'll try to answer things I haven't madeclear. The Water-based Battery Cell Environment  Aqueous batteries tend to charge water into O 2  (positrode) and H 2  (negatrode) gasses. In acid,hydrogen generation starts to occur at 0.0 volts or anything negative: this is the reference voltage againstwhich all other reactions are measured. Whether a substance can be used inside a rechargeable celldepends on it charging below the voltage where gas is produced instead. Gas generation is more and more likely with increasing voltage above 1.23 volts, but the exact voltagevaries with electrode substance and additives, temperature, and pH. Any amount over the theoreticalgassing limit, at which gas isn't generated, is called the overvoltage . In acid, gas generation voltages shift to inhibit oxygen generation and hydrogen generation occurs moreeasily. Eg, a lead-acid battery allows the lead oxide to lead sulfate reaction to work at +1.7 volts. The leaddioxide would spontaneously discharge itself at that voltage in salt or alkaline solution. However, the leadmetal to sulfate reaction is also just under the limit at -.35 volts. On the other hand, in alkali, oxygen gas generation is encouraged and hydrogen more inhibited. Thecommon alkaline nickel positrode (+.5 volts) is just below the oxygen overvoltage at room temperature,and zinc just works at -1.24 volts. The 0.0 volts in acid hydrogen voltage, in alkali is -.833 volts. Theinverse of this voltage plus the +.49 volts of nickel gives us a theoretical open circuit voltage of the nickel-metal hydride alkaline battery, 1.32 volts. Oxygen overvoltage falls a bit with temperature, and above 40ºC simple nickel electrodes won't chargeproperly. The electrode substance is also significant, and small amount of a high overvoltage potential substanceas an additive can increase the overvoltage so that the main substance works better, or works at highertemperatures. To improve zinc's performance in alkaline solution (-1.24 volts), the traditional additive was2.5-4% mercury oxide. Later, owing to mercury's toxicity, transition metals (gallium, indium, tin andbismuth) or their oxides were tried and found to work well even in amounts under .5%. In an Indianexperiment with sealed Ni-Fe alkaline cells, .5% bismuth sulfide (Bi2S3) was used to reduce the hydrogenbubbling in the iron negatrode. Heavy transition metals such as antimony are also used to improve lead-acid cell charge performance. In the case of manganese as a negatrode, adding 1% antimony sulfide raises the hydrogen overvoltageabove manganese's charging voltage. This is the only reason it works at all. Without it, the overvoltageseems to be right on the edge: the manganese may or may not charge, but it bubbles hydrogen as it doesand gradually discharges itself to hydroxide, bubbling hydrogen. Thus manganese has never been usedbefore as a negatrode. Its higher reaction voltage, made workable by the antimony sulfide, gives a -Mn battery an edge in energy density over any other. (Ni-Mn is higher voltage and longer lasting than Ni-Zn,making higher energy cells of about 1.7 nominal volts. In fact, NiMn alkaline cells may last indefinitely.) There are lots of even higher voltage reactions that it's hard to conceive of making work with anyadditive, such as aluminum to aluminum hydroxide at -2.3 volts in alkali. That surely will never be enticedto charge or to hold a charge in any aqueous solution. The gas produces pressure inside the cell, and the pressure problem increases with battery size, sosealed batteries are small. In addition, H2 has proven almost impossible to get rid of in sealed cells.Pressure would just build up until the cell burst. So sealed alkaline batteries are made with the negatrodeslarger than the positrodes. The positrodes bubble oxygen first, and the cells are also made as dry cellswith empty spaces that gas can pass through. The oxygen migrates to the negatrode, discharges some of the substance (making heat), and prevents complete charging of the negatrode. This gets rid of theoxygen, and prevents the negatrode from bubbling hydrogen gas, preventing mild overcharging frombursting the cell. converted by Web2PDFConvert.com
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