A123 20ah pouch where abouts full tabs $
- Thread starter 999zip999
- Start date
docnjoj
1 GW
Only to the copper tab but the alloy one would be difficult.
otherDoc
otherDoc
999zip999
100 TW
It looks to me as the cooper one but for a few dollars more full tabs so who needs it. I'm done with buying used cells. But might buy one for a cheese grater.
oatnet
1 MW
Punx0r said:
Nope, the tabs heat-sink into the cell structure. It is my experience that you can't get the tabs hot enough to solder well, and if you did it would damage the cell. Every single attempt to solder these tabs I have seen has resulted in the solder patch eventually flaking off due to the tab material flexing, so I have not seen one actually bond with the metal of tab.
Those clamp-on tab cell terminations are probably what perforated the tabs... One could probably install new clamp-on terminations, if one could afford the tool that installs them.
-JD
agniusm
1 MW
Boys, is victpower magic word from now?? Back here in Lithuania we did group buy from ONSpower. All turned out well. Received USA made cells, full tabs. Now we organizing second one next month. I am not on any side but you can try explore other suppliers. Here is an email for ONSpower, contact Cindy and ask for a quote. Good luck
999zip999
100 TW
Can you fill us in on the price ?
agniusm
1 MW
+50 cells i was quoted 28usd/pcs
arkmundi
10 MW
thanks. as opposed to 16.50 per from Victpower, for short tabs, which are working just fine for me.agniusm said:
ev99saturn
100 µW
- Joined
- Nov 21, 2011
- Messages
- 8
I purchased 400 cells from OSN in january 2012. They are all full tabs, all new, and have been testing out quite well. The capacity of each cell ranges from about 18.8 to over 20 Ah, with the average about 19.3 Ah. I am still building up packs, and have seen no failures yet. 3 out of 8 planned packs are now in my car and working very well. No complaints at all about OSN, and Cindy was very good to work with.
My packs are each 4P12S, at 39.6V nominal. I have pulled over 1000A off the packs, with very minimal temperature change. Those cells are like a firehose for current! My car loves them.
My packs are each 4P12S, at 39.6V nominal. I have pulled over 1000A off the packs, with very minimal temperature change. Those cells are like a firehose for current! My car loves them.
oatnet
1 MW
ev99saturn said:
In a car, with paralleled cells, and a 1000a draw, I am surprised you didn't go for a few of the a123-factory-built 28s3p modules instead. I used them in my last car conversion, and am using them in my current one too. The modules are much cheaper than the single cells, provide proper the cell compression, cell cooling, and support of the tabs (flexing from vibrations will lead to failure of the tab material), at the lightest weight possible. Not to mention the benefits of no assembly required.
-JD
arkmundi
10 MW
ev99saturn
100 µW
- Joined
- Nov 21, 2011
- Messages
- 8
The car is a new build and the 1000 amp limit is only temporary until the motor brushes are fully seated, then it goes up. 96S4P provides the planned amps and is also the right mix of volts, physical pack size, weight and range for this car. 3P is not quite enough amps.
I was not aware that A123 would sell packs for an individual vehicle! That would certainly make the job far easier. How expensive and available are they?
Wayne
I was not aware that A123 would sell packs for an individual vehicle! That would certainly make the job far easier. How expensive and available are they?
Wayne
oatnet said:In a car, with paralleled cells, and a 1000a draw, I am surprised you didn't go for a few of the a123-factory-built 28s3p modules instead. I used them in my last car conversion, and am using them in my current one too. The modules are much cheaper than the single cells, provide proper the cell compression, cell cooling, and support of the tabs (flexing from vibrations will lead to failure of the tab material), at the lightest weight possible. Not to mention the benefits of no assembly required.
-JD
oatnet
1 MW
ev99saturn said:
Nice kw, what's your platform? Some of us have been buying used modules from China, about $1,600 for the 28s3p shipped air:
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=38901&start=285#p575820
In the bay window Bus conversion (scroll past the PSI pack):
http://endless-sphere.com/forums/viewtopic.php?f=34&t=8012&start=150#p552134
999zip999
100 TW
JD so it's a clamp then the laser weld. Clamped first ?
ev99saturn
100 µW
- Joined
- Nov 21, 2011
- Messages
- 8
The finished packs will add up to about 24.4 kWh at 100% DOD. The car is the one pictured in my avatar, a 1965 AC Cobra replica kit car. It has a TransWarP 11HV motor, a NetGain Controls 360V/1400A controller and with the completed packs will run at 350 kW.The 28S3P and 7S3P packs were unfortunately not available when I purchased my cells.
I am build my packs 12S4P, using silver plated aluminum plates to clamp cell tabs together. Finished packs include sensing/balancing taps and temperature probes. Tabs are passed through waterjet cut slits in the lower plate, bent over and clamped with a top plate.
Here are a few pictures showing a pack ready for cell taps and box, and also the first three 40V packs installed in the car.
oatnet said:
Attachments
arkmundi
10 MW
Really impressive work! I'll get around to converting my 2005 Ford Escape Hybrid to pure electric one of these days. Because of what I believe was a design flaw, the ICE threw a rod, rendering the vehicle undriveable. Everything else, however is OK. I'll pick up on your lead when I can dedicate the time. Many thanks.ev99saturn said:
oatnet
1 MW
ev99saturn said:
Nice, that will indeed be an interesting build - when you are running at 80% efficiency, that will be close to 400hp, and you will be disappating 70kw of just heat - the heat load is more than many EVs supply in motive power. What is your target weight for the build?
A build this big is worthy of its own thread in the large EV section: http://www.endless-sphere.com/forums/viewforum.php?f=34
-JD
