# Can you mount A123 pouch cells upside down?



## Guest (Feb 29, 2012)

Batterypoweredtoad said:


> or horizontally, or on their sides, etc...?
> 
> Thanks,
> Josh


It's a vacuum sealed pouch. No avenue for leaking. Unless of course you bust the seal. I see no reason why not. We are going to mount fully on their flat sides. Protect them from chaffing and puncture.


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## kerrymann (Feb 17, 2011)

I agree that there is little/no risk of leaking but I wonder about the anode and cathode configuration. For some of the larger prismatics it has be theorized that not mounting terminals up can reduce cycle life up to 60%. The general idea being the cathode could sag (Horizontal would be the worst). Like most DIY battery questions, I have not seen any hard data supporting this. I am planning on mounting mine up but I think there is a marginal saftey increase in having them upside down because of the decreased chance of dropping something on an open pack (like a wrench) and causing a short.


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## Guest (Mar 1, 2012)

Sagging? No there is no place for them to sag, as they are encased in a plastic box for the TS style cells. Being upright would be the same as upside down except the tabs are facing down for the pouch cells. On the TS cells there is a gap between the inner pack and the top of the inside of the cell where electrolyte can accumulate. Sagging is not an issue if you mount those sideways or upright. Those are not supposed to be mounted upside down. There is no hard data on the vacuum packed and sealed pouch cells because there is no issue from what I see. You can make all sorts of claims but since they are vacuum packed and sealed there is no chance of sagging. Like all cells you need to support the cells no matter how you mount them. 

Why do you want them upside down anyway? What is the issue that requires that sort of mounting? 

Pete


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## Batterypoweredtoad (Feb 5, 2008)

gottdi said:


> Why do you want them upside down anyway? What is the issue that requires that sort of mounting?
> 
> Pete


I'm not sure if you were talking to me or Kerryman, but I will answer . I was brainstorming a pack that involved the cells laying flat, tab to tab, and one tab offset, to make the series connection. The paralleled cells would be stacked. Going by what measurements I could find, the cells and tabs are almost perfectly spaced for this. Doing this I could design a 4P100S pack that is 36"Wx37"Lx6"H. Multiples of 18" wide by whatever length and height would be possible. This would make a nice underfloor pack possible in many vehicles. Your height is only determined by the thickness of how many you parallel and your associated hardware.


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## Guest (Mar 1, 2012)

Batterypoweredtoad said:


> I'm not sure if you were talking to me or Kerryman, but I will answer . I was brainstorming a pack that involved the cells laying flat, tab to tab, and one tab offset, to make the series connection. The paralleled cells would be stacked. Going by what measurements I could find, the cells and tabs are almost perfectly spaced for this. Doing this I could design a 4P100S pack that is 36"Wx37"Lx6"H. Multiples of 18" wide by whatever length and height would be possible. This would make a nice underfloor pack possible in many vehicles. Your height is only determined by the thickness of how many you parallel and your associated hardware.


Kind of both. The flat pack situation is very possible with these cells. It is being developed as we speak exactly as you state by a few folks. I for one am working on a setup for a flat pack for the VW platform. My issue is keeping the cells from moving around. I still think they need a simple container to contain movement and to help give some added protection to the pouch both from chaffing and puncture. Beyond that I see no reason to have an extensive container except if your going to add an extra flat pan to the bottom of the vehicle. My idea is to build a flat chassis that will be the battery container and chassis of the vehicle. That way there is no extra pan sticking below the normal bottom of the vehicle. Sort of like Tesla but on a smaller scale. We can keep the center the same for the VW but build taller sides and internal floor which will house the cells on either side of the center where you need your shift rod anyway. We have a builder that builds custom chassis for the VW and it is nearly perfect for our needs except it needs to be a bit taller and for a full length VW instead of a Buggy. 

So yes if you plan on placing them on the sides you can with no problem except keeping them from shifting around in the belly pan you create. So my protective covers will mount to the pan and enclose the cells tightly but it will all be accessible if needed to replace or repair any damage that may occur. 

Pete


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## Bowser330 (Jun 15, 2008)

semi-off topic, is anyone finding places that sell the pouch/tap cells in modules, for those of us that cant deal with custom DIY busbar & screw mounts?


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## Guest (Mar 1, 2012)

First we must find a suitable way to do that that will be safe and secure. Testing is in progress. It also depends upon what kind of setup and space requirements are needed. So each is truly custom. Until a basic form comes along your on your own. There are ideas but so far the standard TS style cells are what you have unless you want to experiment which is what we are all doing with the pouch cells. So far the flat pack is going to work well with few modifications. Making the connections is easy. A good vice, drill and hack saw will do as well as a good tap and of course a supply of material which is always available on ebay. Go for it. If yours is the best then you get to sell kits. 

Pete


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## Brute Force (Aug 28, 2010)

Bowser,

Like these?

http://www.youtube.com/watch?v=sAhLdCTq6vQ

I'm in negotiations...


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## Guest (Mar 2, 2012)

Complex. That is not what we are trying to do. We want good but not complex. We want simple and safe and secure. Why go with the complex. It looks good but does it need to be like that?


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## Ziggythewiz (May 16, 2010)

That's probably the pack type they're rolling out for military, OEM, and other deep pockets.


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## Brute Force (Aug 28, 2010)

Once upon a time I thought I had seen the phrase "can be mounted in any orientation" in the spec sheet for the AMP20 cells. Unfortunately, I cannot find that reference.

Bowser asked about commercially available modules. They exist and will be available to the public soon. Now that A123 is selling them to OEMS (Fisker, Smith, etc.), they have to provide them as service components to the people that purchase those vehicles (through the dealerships). Spendy, yes. But expect to see them trickling into the aftermarket in the near future.

I thought it would be informative to see how A123 intended for their cells to be incorporated into a pack. Good place to start discussions on how to build a battery module using AMP20 cells. Frankly, I believe their solution is elegant. While the laser welded accordion buss bars are far beyond DIY capabilities, it cannot be any simpler. Stack the cells, band them together, add buss bars. Same process for building a DIY pack, except the buss bar consists of lots spacers and screws. Take a look at Ron's LiPo build. While possible to do at home, it is certainly not less complex.


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## Batterypoweredtoad (Feb 5, 2008)

Brute Force said:


> Bowser,
> 
> Like these?
> 
> ...


How do they connect the tabs to the Bussbar?


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## Brute Force (Aug 28, 2010)

The tabs are laser welded to the bus bars.

As a side note, while one cell tab is aluminum and the other is copper, they are both nickel plated. This solves the aluminum/copper dissimilar metal connection debate.


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