Can you mount A123 pouch cells upside down? - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > EV Conversions and Builds > Batteries and Charging

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 02-29-2012, 06:39 AM
Batterypoweredtoad Batterypoweredtoad is offline
Senior Member
 
Join Date: Feb 2008
Location: Gainesville, FL
Posts: 431
Batterypoweredtoad is on a distinguished road
Default Can you mount A123 pouch cells upside down?

or horizontally, or on their sides, etc...?

Thanks,
Josh
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 02-29-2012, 07:58 AM
gottdi
Guest
 
Posts: n/a
Default Re: Can you mount A123 pouch cells upside down?

Quote:
Originally Posted by Batterypoweredtoad View Post
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.
Reply With Quote
  #3  
Old 02-29-2012, 11:39 PM
kerrymann kerrymann is offline
Senior Member
 
Join Date: Feb 2011
Location: Parker, CO
Posts: 296
kerrymann is on a distinguished road
Default Re: Can you mount A123 pouch cells upside down?

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.
__________________
1994 Mazda Miata EV Dual Warp 9's, Soliton1, A123s
1986 GL1200 Trike, 196V, 9"ADC, SLAs = RETIRED
2013 Chevy Volt
Remember that your EV is only as clean as your power grid. Go SOLAR!
Reply With Quote
  #4  
Old 03-01-2012, 12:03 AM
gottdi
Guest
 
Posts: n/a
Default Re: Can you mount A123 pouch cells upside down?

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
Reply With Quote
  #5  
Old 03-01-2012, 10:49 AM
Batterypoweredtoad Batterypoweredtoad is offline
Senior Member
 
Join Date: Feb 2008
Location: Gainesville, FL
Posts: 431
Batterypoweredtoad is on a distinguished road
Default Re: Can you mount A123 pouch cells upside down?

Quote:
Originally Posted by gottdi View Post

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.
Reply With Quote
  #6  
Old 03-01-2012, 12:10 PM
gottdi
Guest
 
Posts: n/a
Default Re: Can you mount A123 pouch cells upside down?

Quote:
Originally Posted by Batterypoweredtoad View Post
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
Reply With Quote
  #7  
Old 03-01-2012, 12:14 PM
Bowser330 Bowser330 is offline
Senior Member
 
Join Date: Jun 2008
Posts: 1,682
Bowser330 is on a distinguished road
Default Re: Can you mount A123 pouch cells upside down?

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?
Reply With Quote
  #8  
Old 03-01-2012, 01:12 PM
gottdi
Guest
 
Posts: n/a
Default Re: Can you mount A123 pouch cells upside down?

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
Reply With Quote
  #9  
Old 03-01-2012, 07:51 PM
Brute Force Brute Force is offline
Senior Member
 
Join Date: Aug 2010
Posts: 148
Brute Force is on a distinguished road
Default Re: Can you mount A123 pouch cells upside down?

Bowser,

Like these?

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

I'm in negotiations...
Reply With Quote
  #10  
Old 03-01-2012, 08:09 PM
gottdi
Guest
 
Posts: n/a
Default Re: Can you mount A123 pouch cells upside down?

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?
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 12:16 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Ad Management by RedTyger