Talk:Nickel-Iron Battery - Revision history

Gregortheinventor at 04:08, 25 June 2011

2011-06-25T04:08:53Z

← Older revision		Revision as of 04:08, 25 June 2011
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	Okay, actually while I'm here, I have been meaning to give a status report because it looks like I am more or less done with this section of the project as my time is now being consumed trying to get some progress on some of the organizational issues.		Okay, actually while I'm here, I have been meaning to give a status report because it looks like I am more or less done with this section of the project as my time is now being consumed trying to get some progress on some of the organizational issues.
			I moved it to the "current progress section"
			[[User:Gregortheinventor\|Gregor]] 23:21, 22 June 2011 (PDT)

	~~Basically, having gone through all those patents and documents and so much more (check the edit history) my recommendation as to how to proceed is:~~

	~~1. Obtain a a changhong battery.~~
	2. Performance test it with a battery analyzer fr maybe 20 cycles to collect a bunch of data regarding charge discharge efficiency at various states of charge etc. This should be available from the manufacturer, but I have found that it is not in fact. Probably for marketing reasons. They figure you will just cross your fingers and buy it anyway.

	~~We need this info anyway so we know what we are competing against~~ in the ~~market~~.		==Proposed prototype==
			A practical plan for the prototypes and eventual production (the process for which is more intimately intertwined with the design than it is for e.g. the lifetrac) will be produced after the documents listed in the sticking points section are obtained and read.

	~~3. Dismantle the electrodes to look at their construction. In all my travels I have not been able~~ to ~~determine how pocket plate electrodes~~ are ~~made exactly this [http://img.directindustry.com/pdf/repository_di/20330/pocket-plate-range-data-90472_4b.jpg]~~ is ~~about it. Although there are many different ways and the basic idea is just to pack the~~ material ~~in at 2000 to 4000 psi~~ (~~it becomes a solid mass probably a bit like soapstone~~) and ~~then hold it at a pressure of about 40 psi~~. ~~The main purpose of the pressures is to decrease the contact resistance between the constituent parts.~~		The reason these relatively difficult to make electrode geometries are used instead of just plates is (mostly) in pursuit of higher active material utilization (major impact on cost) and higher discharge rates, and reasonable energy and power density.

	4. ~~If the performance is higher than expected they may have developed new additives~~, ~~especially if the efficiency~~ is ~~better than 60%~~. ~~Check~~ the ~~battery~~ for ~~patent numbers. Contact~~ the ~~company to see if~~ the ~~battery or any part of it~~ is ~~patented. Look up the patents~~.		It is possible to make a battery from active nickel oxyhydroxide particles of 200 mesh that is rated at 0.1 C or so, which is about 0.075 mm. The surface are is one of the main determining factors for the reaction rate, and therefore the acceptable discharge rate (although I guess a plate might decrease the resistance between the current collector and the active material which is another significant factor).

	~~Under US patent system~~, ~~they cannot conceal this information in~~ the ~~slightest -~~ it ~~must~~ be ~~fully made known -~~ or the ~~patent~~ is ~~not enforceable~~. ~~That is why stuff usually has "protected by patent x"~~ on it.		But if you have a surface(backed by metal) then the ratio of volume/area is T^3/T^2=T, where T is the thickness, whereas with a sphere it is (pid^3/6)/(pid^2)=d/6 where d is the diameter, thickness of the layer would have to be therefore 1/6th of 0.075 mm to have the same volume/surface area with a plate as a particle, or 0.0125 mm, 12.5 microns. If you use both sides of the plate then you get 0.0025cm*1cm^2=1/4000 cm^3, density of nickel hydroxide is 4 g per cc, so the weight of material per sq cm of plate is 1 milligram. You would get 10 grams per square meter of plate, which could be increased slightly (depending on plate thickness) with perforations, and you could make the plate foil 0.01 mm thick, but you still would need a lot of foil. It would have to be packed together in some way to achieve reasonable density, and plating it with nickel would be that much more work.

	~~5. If there are not patent problems, analyze~~ the active material by ~~microscopic~~ and ~~chemical analysis~~ to ~~determine~~ what ~~the additives are~~ so we can ~~copy them. Fear not, this is not unethical as this is SOP in manufacturing~~.		Also that 200 mesh is with cobalt compound additive to improve conductivity of the active material mass and the contact resistance between the particles, which could change things a lot. Without it the layer would have to be thinner to get the same internal resistance. How much needs to be verified by finding the conductivity of the material with and without additive. Secondly those documents listed below will provide information about exactly what sort of surface area to volume ratio leads to what sort of battery characteristics, so we can decide if a higher v/a ratio may be acceptable.

	~~6. Design battery Open battery prototype I while keeping the production line in mind. To keep costs low~~ there ~~will probably~~ need ~~to be~~ a ~~bit of custom equipment for electroplating etc which~~ can ~~be made with~~ the ~~replab but not really be part of it~~.		Also, there is no need for a self protection mechanism, and you can't have high current density and and current limiting at the same time. Lower internal resistance is always good, within the range that is attainable.

	7. ~~Build, test~~.		Lastly the nickel hydroxide would probably fall off the electrode, unless held in place in some way. With a foam or other porous mesh-like electrode that is overcome with the mechanical support that the matrix provides.

	I think it is most probably by a ways that pocket plate is the best, for a variety of reasons, mostly simplicity of manufacture, not tubular and not sintered and not mesh and not teflon bonded and not nickel plated steel wool. ~~Changhong even uses pocket plates for their starting lighting ignition batteries so it should be good.~~		[[Image:nife_childsplay.png]]

	[[User:Gregortheinventor\|Gregor]] 23:21, 22 June 2011 (PDT)		I took this off the main page and moved it here because it is more chatty really though maybe some parts shoudl be integrated witht eh future prototypes section. [[User:Gregortheinventor\|Gregor]] 21:08, 24 June 2011 (PDT)

Gregortheinventor at 06:21, 23 June 2011

2011-06-23T06:21:55Z

← Older revision		Revision as of 06:21, 23 June 2011
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	The great thing about NiFe chemistry is that it does not tend to degrade very much. NiFe batteries built 50-100 years ago are still in operation today, working just as well as they did then. Even in the event of a rebuild, the chemistry should be simple enough to recover the vast majority of the Nickel in the battery. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)		The great thing about NiFe chemistry is that it does not tend to degrade very much. NiFe batteries built 50-100 years ago are still in operation today, working just as well as they did then. Even in the event of a rebuild, the chemistry should be simple enough to recover the vast majority of the Nickel in the battery. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)

			sustainability: There should be no problem with that no matter how we work it as long as no toxic chemicals are used. Just grind the cells up or dismantle them and take the material out and replace with new stuff. Might have to replace the pockets too if the nickel comes off.

			Okay, actually while I'm here, I have been meaning to give a status report because it looks like I am more or less done with this section of the project as my time is now being consumed trying to get some progress on some of the organizational issues.

			Basically, having gone through all those patents and documents and so much more (check the edit history) my recommendation as to how to proceed is:

			1. Obtain a a changhong battery.
			2. Performance test it with a battery analyzer fr maybe 20 cycles to collect a bunch of data regarding charge discharge efficiency at various states of charge etc. This should be available from the manufacturer, but I have found that it is not in fact. Probably for marketing reasons. They figure you will just cross your fingers and buy it anyway.

			We need this info anyway so we know what we are competing against in the market.

			3. Dismantle the electrodes to look at their construction. In all my travels I have not been able to determine how pocket plate electrodes are made exactly this [http://img.directindustry.com/pdf/repository_di/20330/pocket-plate-range-data-90472_4b.jpg] is about it. Although there are many different ways and the basic idea is just to pack the material in at 2000 to 4000 psi (it becomes a solid mass probably a bit like soapstone) and then hold it at a pressure of about 40 psi. The main purpose of the pressures is to decrease the contact resistance between the constituent parts.

			4. If the performance is higher than expected they may have developed new additives, especially if the efficiency is better than 60%. Check the battery for patent numbers. Contact the company to see if the battery or any part of it is patented. Look up the patents.

			Under US patent system, they cannot conceal this information in the slightest - it must be fully made known - or the patent is not enforceable. That is why stuff usually has "protected by patent x" on it.

			5. If there are not patent problems, analyze the active material by microscopic and chemical analysis to determine what the additives are so we can copy them. Fear not, this is not unethical as this is SOP in manufacturing.

			6. Design battery Open battery prototype I while keeping the production line in mind. To keep costs low there will probably need to be a bit of custom equipment for electroplating etc which can be made with the replab but not really be part of it.

			7. Build, test.

			I think it is most probably by a ways that pocket plate is the best, for a variety of reasons, mostly simplicity of manufacture, not tubular and not sintered and not mesh and not teflon bonded and not nickel plated steel wool. Changhong even uses pocket plates for their starting lighting ignition batteries so it should be good.

			[[User:Gregortheinventor\|Gregor]] 23:21, 22 June 2011 (PDT)

Colind at 02:13, 21 June 2011

2011-06-21T02:13:08Z

← Older revision		Revision as of 02:13, 21 June 2011
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	The thing is that this is the development page not an encyclopedia entry, though. I don't think we can afford to oversimplify if we are going to produce something which can compete well with commercial models. The construction and chemistry are intimately intertwined. [[User:Gregortheinventor\|gregor]]gregortheinventor		The thing is that this is the development page not an encyclopedia entry, though. I don't think we can afford to oversimplify if we are going to produce something which can compete well with commercial models. The construction and chemistry are intimately intertwined. [[User:Gregortheinventor\|gregor]]gregortheinventor

			The chemistry and details of construction are not oversimplified in this article. I am not suggesting removing the additional information--I am suggesting creating a new article to house it. Leaving it here with construction information leaves the article extremely cluttered. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)

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	If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor		If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor

			The cells are isolated to prevent shorting between cells. Were the electrolyte allowed to flow freely between cells, the end result would not be a series stack, so a highly inefficient 1.2V battery would result. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)
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	One idea might be to use a colloidal form of CaOH in a noble gas atmosphere with suspended Anatase titanate nanotube (very easy to produce) homogeneous throughout the gel, but that would have to be tested and evaluated.--[[User:James Clark\|James Clark]] 06:47, 11 June 2011 (PDT)		One idea might be to use a colloidal form of CaOH in a noble gas atmosphere with suspended Anatase titanate nanotube (very easy to produce) homogeneous throughout the gel, but that would have to be tested and evaluated.--[[User:James Clark\|James Clark]] 06:47, 11 June 2011 (PDT)

			So many suggestions here seem to fall within the realm of 'high tech.' Remember that this battery was very successfully built and marketed in the early 20th century. For the purposes of OSE, there is no need to complicate. Simpler construction also means more reliable and resilient use. Complex electrode geometries tend to mean degradation over time. A classic example are the 'fingers' or 'tendrils' formed in lead acid batteries which will ultimately short them out. Of course, additives can mitigate the problem, but it would be far simpler just to avoid it all together and aim for a reasonably high surface area, but a high capacity battery. This would result in a more robust solution which would easily store 1kWh or possibly even much more. The size and weight of the battery are not critical factors. Marcin informed me that their primary use will be in storing solar/wind energy for off-grid applications. So much of the information added to this article is irrelevant to that purpose. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)
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	'''Sustainability'''		'''Sustainability'''
	One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)		One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)

			The great thing about NiFe chemistry is that it does not tend to degrade very much. NiFe batteries built 50-100 years ago are still in operation today, working just as well as they did then. Even in the event of a rebuild, the chemistry should be simple enough to recover the vast majority of the Nickel in the battery. [[User:Colind\|Colind]] 19:13, 20 June 2011 (PDT)

James Clark at 13:47, 11 June 2011

2011-06-11T13:47:11Z

← Older revision		Revision as of 13:47, 11 June 2011
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	If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor		If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor
	-----		-----
	One idea might be to use a colloidal form of CaOH in a noble gas atmosphere with suspended Anatase titanate nanotube (very easy to produce) homogeneous throughout the gel, but that would have to be tested and evaluated.		One idea might be to use a colloidal form of CaOH in a noble gas atmosphere with suspended Anatase titanate nanotube (very easy to produce) homogeneous throughout the gel, but that would have to be tested and evaluated.--[[User:James Clark\|James Clark]] 06:47, 11 June 2011 (PDT)
	-----		-----
	'''Sustainability'''		'''Sustainability'''
	One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)		One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)

James Clark at 13:28, 11 June 2011

2011-06-11T13:28:38Z

← Older revision		Revision as of 13:28, 11 June 2011
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	If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor		If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor
			-----
			One idea might be to use a colloidal form of CaOH in a noble gas atmosphere with suspended Anatase titanate nanotube (very easy to produce) homogeneous throughout the gel, but that would have to be tested and evaluated.
	-----		-----
	'''Sustainability'''		'''Sustainability'''
	One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)		One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)

Bhm at 10:18, 9 June 2011

2011-06-09T10:18:04Z

← Older revision		Revision as of 10:18, 9 June 2011
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	If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor		If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor

			-----
			'''Sustainability'''
			One thing that haven't been addressed as far as I can tell is recycling which will also help bringing cost down over time. In order for any technology to be sustainable you need a cradle to cradle approach. So my question is: When NiFe cells gets worn out how do we reclaim materials especially the nickel? --[[User:Bhm\|Bhm]] 03:18, 9 June 2011 (PDT)

Gregortheinventor at 19:56, 3 June 2011

2011-06-03T19:56:47Z

← Older revision		Revision as of 19:56, 3 June 2011
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	Of course a decent CAD package should be able to do the thermal modeling, so when we have the homework done and can move on to the design stage that is one of the things that should be given due consideration. But from basic principles I wouldn't expect it to be a problem, a vertical surface looses about 25 watts per degree to convection in air at around room temp so say it was a 1Kw battery which has a surface area of a meter, and the charge efficiency is 80% (which is what the changhong batteries are) then we charge it at 0.2 C rate well-past worst case scenario in a photovoltaic system (since the batteries are usually much larger than the solar collector peak output) that's 200 watts *0.8 =16 watts. the surface are of a 1Kw hour battery, the energy density is around 30 Wh per liter according to wikipedia (which is just a ballpark since it will vary substantially with design of course) so 33 liters for a 1 kWh battery if i is a cube then 32 cm on a side , suppose the 4 sides and total are 5000 sq cm that is 0.5 square meters.		Of course a decent CAD package should be able to do the thermal modeling, so when we have the homework done and can move on to the design stage that is one of the things that should be given due consideration. But from basic principles I wouldn't expect it to be a problem, a vertical surface looses about 25 watts per degree to convection in air at around room temp so say it was a 1Kw battery which has a surface area of a meter, and the charge efficiency is 80% (which is what the changhong batteries are) then we charge it at 0.2 C rate well-past worst case scenario in a photovoltaic system (since the batteries are usually much larger than the solar collector peak output) that's 200 watts *0.8 =16 watts. the surface are of a 1Kw hour battery, the energy density is around 30 Wh per liter according to wikipedia (which is just a ballpark since it will vary substantially with design of course) so 33 liters for a 1 kWh battery if i is a cube then 32 cm on a side , suppose the 4 sides and total are 5000 sq cm that is 0.5 square meters.

	If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient.		If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient. -gregor

Gregortheinventor at 19:55, 3 June 2011

2011-06-03T19:55:28Z

← Older revision		Revision as of 19:55, 3 June 2011
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	The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)		The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)

			The thing is that this is the development page not an encyclopedia entry, though. I don't think we can afford to oversimplify if we are going to produce something which can compete well with commercial models. The construction and chemistry are intimately intertwined. [[User:Gregortheinventor\|gregor]]gregortheinventor

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	I was looking at the diagram showing the battery construction and see that in the top view the plates forming the cells are arranged in 2 rows of "boxes" with some number of boxes along the battery depending on how big it is. Apparently the batteries can produce a fair bit of heat when they are operating and it would therefore be nice to be able to cool them. If you made each of the boxes watertight along the long axis, but allowed it to flow from one box to the next along the rows you could push electrolyte from left to right on that picture. An opening on boxes on the ends which connects across the middle wall would allow fluid to flow either clockwise or counter clockwise slowly around the battery. Given the way the electrodes are arranged flow clockwise would circulate the electrolyte from anode to cathode and the other way would go from cathode to anode. Depending on which way you circulated the fluid the battery would either be easier to charge or easier to discharge. The whole cycle can be driven by slow speed fans or pumps in the battery, making the fans reversible would let you always pump the cooling fluid in the direction that favors what you are doing over the long term (either charging or discharging). As the fluid circulates around the loop you divert some of it through a heat exchanger to cool the battery, the flow should keep most of it at roughly the same temperature even at slow flows I think (you would want the flow slow anyway as I think very fast at all and the ion transport rate would be way faster than the reaction rate and it would mix too much. Anyway, just a thought I had while looking at the diagram. -[[User:Andrew Buck\|Andrew Buck]] 20:34, 2 June 2011 (PDT)		I was looking at the diagram showing the battery construction and see that in the top view the plates forming the cells are arranged in 2 rows of "boxes" with some number of boxes along the battery depending on how big it is. Apparently the batteries can produce a fair bit of heat when they are operating and it would therefore be nice to be able to cool them. If you made each of the boxes watertight along the long axis, but allowed it to flow from one box to the next along the rows you could push electrolyte from left to right on that picture. An opening on boxes on the ends which connects across the middle wall would allow fluid to flow either clockwise or counter clockwise slowly around the battery. Given the way the electrodes are arranged flow clockwise would circulate the electrolyte from anode to cathode and the other way would go from cathode to anode. Depending on which way you circulated the fluid the battery would either be easier to charge or easier to discharge. The whole cycle can be driven by slow speed fans or pumps in the battery, making the fans reversible would let you always pump the cooling fluid in the direction that favors what you are doing over the long term (either charging or discharging). As the fluid circulates around the loop you divert some of it through a heat exchanger to cool the battery, the flow should keep most of it at roughly the same temperature even at slow flows I think (you would want the flow slow anyway as I think very fast at all and the ion transport rate would be way faster than the reaction rate and it would mix too much. Anyway, just a thought I had while looking at the diagram. -[[User:Andrew Buck\|Andrew Buck]] 20:34, 2 June 2011 (PDT)

			I don't think overheating will be a problem from what I have read. A lot of the energy wasted goes into producing h2 and o2. The catalytic converter will get hot though, especially due to it's small size and during overcharge, and this is something that will need to be addressed.

			Of course a decent CAD package should be able to do the thermal modeling, so when we have the homework done and can move on to the design stage that is one of the things that should be given due consideration. But from basic principles I wouldn't expect it to be a problem, a vertical surface looses about 25 watts per degree to convection in air at around room temp so say it was a 1Kw battery which has a surface area of a meter, and the charge efficiency is 80% (which is what the changhong batteries are) then we charge it at 0.2 C rate well-past worst case scenario in a photovoltaic system (since the batteries are usually much larger than the solar collector peak output) that's 200 watts *0.8 =16 watts. the surface are of a 1Kw hour battery, the energy density is around 30 Wh per liter according to wikipedia (which is just a ballpark since it will vary substantially with design of course) so 33 liters for a 1 kWh battery if i is a cube then 32 cm on a side , suppose the 4 sides and total are 5000 sq cm that is 0.5 square meters.

			If it is say polyethylene which is about 0.4 W/mK [http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html] and say worst case 5 mm thick. Then that is 0.5/0.0050.4=40 W/K so it would not be a problem. Temperature rise might be less than a degree above ambient.

Andrew Buck: adding a comment about cooling the battery

2011-06-03T03:34:38Z

adding a comment about cooling the battery

← Older revision		Revision as of 03:34, 3 June 2011
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	The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)		The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)

			-----

			I was looking at the diagram showing the battery construction and see that in the top view the plates forming the cells are arranged in 2 rows of "boxes" with some number of boxes along the battery depending on how big it is. Apparently the batteries can produce a fair bit of heat when they are operating and it would therefore be nice to be able to cool them. If you made each of the boxes watertight along the long axis, but allowed it to flow from one box to the next along the rows you could push electrolyte from left to right on that picture. An opening on boxes on the ends which connects across the middle wall would allow fluid to flow either clockwise or counter clockwise slowly around the battery. Given the way the electrodes are arranged flow clockwise would circulate the electrolyte from anode to cathode and the other way would go from cathode to anode. Depending on which way you circulated the fluid the battery would either be easier to charge or easier to discharge. The whole cycle can be driven by slow speed fans or pumps in the battery, making the fans reversible would let you always pump the cooling fluid in the direction that favors what you are doing over the long term (either charging or discharging). As the fluid circulates around the loop you divert some of it through a heat exchanger to cool the battery, the flow should keep most of it at roughly the same temperature even at slow flows I think (you would want the flow slow anyway as I think very fast at all and the ion transport rate would be way faster than the reaction rate and it would mix too much. Anyway, just a thought I had while looking at the diagram. -[[User:Andrew Buck\|Andrew Buck]] 20:34, 2 June 2011 (PDT)

Colin at 05:18, 25 May 2011

2011-05-25T05:18:47Z

← Older revision		Revision as of 05:18, 25 May 2011
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	Let me elaborate on the above. The construction technique I'm envisioning for this battery involves a number of plates, all made from relatively thin sheet steel. Half of which would be plated by nickel oxyhydroxide in the first charging cycle, forming the cathode of each 1.2V cell. The steel should be carbon steel with minimal to no content of other metal. I intend on writing this into the article, but I think that it needs graphics to go along. So, the idea is that the sheets which will be the electrodes would have a tab cut out of a corner with the cnc torch table. Then, these sheets will be placed with the remaining tab (like a tab on a folder) of each plate alternating in a cell. This leaves two sets of 'tabs,' one set will be for the anode, and the other for the cathode. With this design, two long steel bars can be welded to the exposed tabs, which should allow for high current capacity, resilience, and rigidity in design. These two bars would be inside the profile of the box when viewing it from the top, so many cells can be placed snugly adjacent to each other, and then welded in series to form a 12V stack. Such a setup should easily handle the highest loads this battery should be capable of driving. [[User:Colin\|Colin]] 20:55, 24 May 2011 (PDT)		Let me elaborate on the above. The construction technique I'm envisioning for this battery involves a number of plates, all made from relatively thin sheet steel. Half of which would be plated by nickel oxyhydroxide in the first charging cycle, forming the cathode of each 1.2V cell. The steel should be carbon steel with minimal to no content of other metal. I intend on writing this into the article, but I think that it needs graphics to go along. So, the idea is that the sheets which will be the electrodes would have a tab cut out of a corner with the cnc torch table. Then, these sheets will be placed with the remaining tab (like a tab on a folder) of each plate alternating in a cell. This leaves two sets of 'tabs,' one set will be for the anode, and the other for the cathode. With this design, two long steel bars can be welded to the exposed tabs, which should allow for high current capacity, resilience, and rigidity in design. These two bars would be inside the profile of the box when viewing it from the top, so many cells can be placed snugly adjacent to each other, and then welded in series to form a 12V stack. Such a setup should easily handle the highest loads this battery should be capable of driving. [[User:Colin\|Colin]] 20:55, 24 May 2011 (PDT)

			I've added an mspaint rendition of what such a battery would look like in concept. If anyone possessing proper CAD skills wants to improve it, please go ahead and replace it. [[User:Colin\|Colin]] 22:18, 24 May 2011 (PDT)

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	The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)		The added information to the article is greatly appreciated, but tends to be overwhelming. At this point, I suggest this article is broken into two segments: chemistry and construction details. Anyone else agree with me? [[User:Colin\|Colin]] 21:26, 24 May 2011 (PDT)