A123 20AHr Pouch Cell Battery Build & Info Thread

Bazaki said:

What is a realistic Max C discharge rate for these cells ? Would 25C for 5 seconds be ok ? And what Voltage can we expect at 25C discharge ?

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If you would check my A123 kit thread, there is a video on ~200 amp discharge for minutes. They are rated 30C peak, i guess 10sec?!
I built myself car battery of these cells and they are cranking starter at 450A+ but thats just for few seconds. I have no info on cycle life of these cells when high discharge rate is used.

Thanks, you still can sell the a123 kits ?
I want to build a 90S2p 297V 40Ah and want to burst 1000A ( car project )

Any idea's for this ?

28s3p victpower pre build A123 models.

Constantly doing high C's would be detrimental to cell life expectancy.

Voltdrop along with cell IR, would also have to factor in your connection method, cable sizes and lengths etc at this level, 500 x 4x10-3 say for cell is 2V dropped in the cell leaving only1.3V for you.
What does that 2V dropped do heats the cell.

You can see that sag in the video i did on running a cell with hardly any tab.

A123 20Ah at 25c. A sag to 1.3 V ?

For my project I want to build a 90s2p pack and with a 1000A controller I want the max performance.

But only for less then 5 sec. Should 15c be realistic ? That would be 600A

Thanks

Might be better with 2P setup.

If you wanna see these puppies tested by the main man Luke, when they were first appearing, this thread should be compulsory viewing for A123 builders, enjoy.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=15093

Check out this battery pack build by ONS Power. It appears to be a clean, simple and inexpensive build assuming you have access to a mill to cut the slots in the top panel. I think this would work with both full and half tabs cells.

http://www.alibaba.com/product-gs/669652272/1000W_Lifepo4_A123_36V_20AH_Battery.html

For those who are interested in a pre-assembled unit, this is a good deal. For a 36V20AH battery pack, I was quoted $360.00. A BMS rated 30/60A was an additional $30. A 36V5A charger was $60. Shipping to California was $100. Total package price $550. These are new full tab A123 cell packs.

Interestingly, the ONS Power price quote for 12 A123 cells are $30 each. So the labor and assembly is free.

If I consider buying 14 (12 plus 2 spares) salvaged A123 cells from Victpower at $16.50 each and add in $116.60 for shipping, it costs $347.60 just for the cells. Now add in an equivalent BMS, charger and shipping for around $100, you are in the $450 price range. So for about $100 price difference, you get a complete assembled, wired, wrapped and boxed battery pack but with new full tabbed A123 cells. Interesting choice here.

FYI. Victpower also offers a pre-assembled 36V20AH A123 pack. Price is $285 for the pack, $33 for 36V3A charger and 182.50 shipping. Total $500.50 but it's possible they might be using salvaged A123 cells and replacing cells looks difficult based on pictures of how the cells tabs were connected. Cannot tell how the tabs were connected with green board material but it was not mechanically connected.

They look interesting. I was wandering, are they in a cardboard box? Are assembled packs without balance leads? Why there are 2 connector for balancing attached to one junction? Seems strange that they sell complete pack for the same price, where's the catch?

I think if you look closely, there are 4 wires coming out of the pack. The thicker gauge Red and Black with white taped ends are to your controller while I assume the other 2 wires are for the connection to the charger. OSN quoted a price of $30 for a built-in 30A/60A BMS so I assuming there is a BMS hidden by the wrapping and "cardboard" box. I will try to get more details on their unit.

Looks to be a great deal. If I buy new full tabbed A123 cells, it doesn't seem to pay to assemble it myself. However, I'm still anxious to build my own pack but I can only save any money if I use the Victpower half tabbed cells.

In their quote, OSN said:

About A123 20Ah cell, our price is US$30pc for quantity 12pcs, so the total cost is US$360, NOT include the shipping cost. We also got an enquiry from you about the 36V 20Ah battery pack made of A123 20Ah cell and we can assemble the battery pack for you for free. That's to say, there's no need for you to pay for the manual fee for the battery pack.

About the 36V 20AH battery pack with 30A/60A BMS built in, our price is US$390.[12*$30(cells)+$30(BMS)=$390] About shipping, as you know no matter it is battery cell or battery pack, they are all considered "hazardous" . Now DHL/EMS do not accept shipping batteries, then we choose TNT/FeDex(about 7 days). It is US$100 for shipping. So the total cost of 36V 20Ah battery with 5A chager is US$450($390+60=$450) +$100(shipping)=US$550.

Did you see the sticker do not crush this side. If I order I ask for 6 of those stickers one for each side. Plus I want to win a date with Nancy Peng I remenber her a little bit older, but it was dark. I like the two sense wire thing do you have to open the box. Maybe the lid just slides off. Good luck with my wishful thinking.

RayGo said:

Check out this battery pack build by ONS Power. It appears to be a clean, simple and inexpensive build assuming you have access to a mill to cut the slots in the top panel. I think this would work with both full and half tabs cells.

http://www.alibaba.com/product-gs/669652272/1000W_Lifepo4_A123_36V_20AH_Battery.html

For those who are interested in a pre-assembled unit, this is a good deal. For a 36V20AH battery pack, I was quoted $360.00. A BMS rated 30/60A was an additional $30. A 36V5A charger was $60. Shipping to California was $100. Total package price $550. These are new full tab A123 cell packs.

Click to expand...

Hey, that is pretty cool build, and a great deal, nice find.

-JD

someone buy one.

I'm chatting with Nancy right now finalizing a couple of items...

I'll be pulling the trigger soon. She hasn't responded to my last email. Probably off for the weekend.

Ambrose

So about 2.0v at 300A for a Cellman 15ah cel in the youtube video from luke.
Then I guess an A123 Cell will have about 2.0v at 400A

So a 90s2p should be able to deliver 180Vx800A = 144KW ???

( I need it for burst for sprints 0-100 km/h )

To your controller terminals, 1mohms of connecting cable and connections is a 1x10-3 x 800A, another 0.8V drop to 1.2V.
Want to have that controller on top of the pack, unless you use large cable.
144kW 8) .

Yo boy's here are the pics of my 12s build and taps. #1 is 12s A123's in the window blind protecter holder with AW-Dogman style sides old tupperware bids. #2 is the Durtlegde build that's man good grace and a sir or thank you Durtlegde again. Thanks. #3 the taps I made between two peices of coppe sheet 18ga. or 16 ga. sgezzed and sodier to fil with 10ga. # 4 is the 12s pack to slide in to the front of under the top tube forward the top channle bolted to the top tube ect. #5 is a finish 12s pack for a rear rack or self contented with pos. neg. hot's 12ga. and both charge wires 14ga. and the two 6s hyperion plugs for the 1420 ect. To charge and balance. these are surounded with yoga mat.

These are my first pics on E.S. SO. I will look at them and I will post soon. Wow did it. Frock uussss. Releiff. haha. Band for life. Than a Lighting bolt.

Pic 2 ( wolf whistle ) nice neat build 8).

2 pic's and lot's of love plus I have more. It's frocking hard but fun learning to press these keys. uyh78uuuuuuuuuuuuuuc t5sdgyu nkmnac.xk<nk.xzn.k.zj;ibrvci9y;hhhhh Wow thanks that felt good. @ more pic's coming soon. Love and peace.

Edit: oh pic #2 I like but pic 4 as i like marlyn with a sheet over her a little bit. Not cheap porn. Cowboy

Megacycler's I have two more pic's for latter So. As said I will now with help be able to picalaty much much more so there. And keep your down under - under So there.

Nice going zipman. Congrats.

Heres my battery in my honda insight lithium pack i built

steveo said:

Heres my battery in my honda insight lithium pack i built

Click to expand...

Fist pic is 50s2p batt

Second one is 32s1p batt

So my build failed today... obviously I did a pretty terrible job attaching the positive aluminum tab to my wire, as it just popped right off! The tab is still whole, although it's kinda messy from the removal of the wire.



So, what do you think would be a better method to attach the main power lead? Soldering doesn't work at all, so I was thinking of purchasing a ring terminal, drilling a hole, and putting a bolt through it. However, the stress of plugging and unplugging shifts the positive tab around a lot, since it is connected to the shorter of the two wires. How can I secure everything so that I don't end up breaking a tab eventually?
I also have a feeling that the heat shrink I put on the tabs (I messed up the coloring ) is a little too stiff, and therefore contributed to the failure. But I want to make sure that the wires are protected from abrasion, etc. What would be a more flexible covering?

I would go with what DRutledge used and what 999Zip999 used as well here: http://endless-sphere.com/forums/viewtopic.php?f=14&t=38761&p=666675#p662450

It's solid and requires no soldering. I plan on doing this when I have some time!