Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
A123 LiFePO4 BAE System Module Teardown
#1
This thing was a bit of a pain... but I got it done.
https://youtu.be/V4JTQ43alDo



jonyjoe505, mike, thunderheart like this post
Reply
#2
Part 2 video completed. 

https://youtu.be/PER-dGjM-m4


thunderheart likes this post
Reply
#3
I'm going to be giving away these cells / modules if anyone is interested.
Reply
#4
Of course! Who wouldn't want free cells?? Smile
Reply
#5
Most definitely. I have a 2000W UPS just sitting here taking up floor space. I could use some 48VDC to pump into it.
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Certified 18650 Cell Reclamation Technician

Please come join in general chit-chat and randomness at Discord Chat (channels: general, 3d-printing, linux&coding, 18650, humor, ...)
(this chat is not directly affiliated with SecondLifeStorage; VALID email req'd)
Reply
#6
Crimp Daddy, thanks for that battery porn! Love it!

P.S. Why did you discharge down to 2.5V/cell when ANR26650M1B's discharge cut-off voltage is 2.0V? And why did you use 10A (10A : 8 = 1.25A/cell i.e. 0.5C) for checking capacity instead of 4A (0.5A x 8).

I think 37% capacity loss is kinda unreal.
LiFePO4: QB26650 2500mAh 50A vs A123 ANR26650M1B: https://youtu.be/GOSkte11lRc

Yinlong LTO Lithium Titanate safety tests: https://youtu.be/eAUYbSDEy6I
Toshiba SCiB LTO Lithium Titanate safety tests: https://youtu.be/XsrRDZxEFQE

XTAR DRAGON 4-slot battery tester review: https://youtu.be/S6yVMsIuauE
Miboxer C4-12 4 slot x 3.0A charger review: https://youtu.be/X-ww1YALjvU
Miboxer C2-4000 smart battery tester review: https://youtu.be/jrbJceNXv1g

Samsung 33J for TESLA: https://youtu.be/7FMxgMmPeh4
Samsung 40T - a high drain 35A 21700 cellhttps://youtu.be/lxgKWiQ9580
Reply
#7
(05-21-2019, 12:58 PM)thunderheart Wrote: Crimp Daddy, thanks for that battery porn! Love it!

P.S. Why did you discharge down to 2.5V/cell when ANR26650M1B's discharge cut-off voltage is 2.0V? And why did you use 10A (10A : 8 = 1.25A/cell i.e. 0.5C) for checking capacity instead of 4A (0.5A x 8).

I think 37% capacity loss is kinda unreal.

Because in real world operational scenarios most 12v equipment would not operate down in the 8v range (2vdc per cell), 10vdc is a more realistic operating range.  

Plus, when you look at the discharge curve of the battery itself, going from 2.5 to 2.0 offers VERY LITTLE in terms of additional capacity, and increases cell degradation at an expedited rate.  After 2.5v the fall off curve is STEEP, which is typical for most LiFePO4 chemistry... curves are flat until they start to roll off then dive.

Two, these are very high drain cells... capable of 70 amps discharge each.  The test preformed at 1.25a each vs 0.5a each literally makes zero difference.  In addition, these would not be used in low drain applications, higher discharge rates give a better real world use case for testing.  Higher rates are preferred so I dont have to wait around all day, and my charger is capable of doing it without an external load.

My testing methods yield pretty accurate results with this charger... 37% loss at the module / pack level is actually the better of the 12v chunks I evaluated.
100kwh-hunter likes this post
Reply
#8
(05-21-2019, 06:15 PM)Crimp Daddy Wrote:
(05-21-2019, 12:58 PM)thunderheart Wrote: Crimp Daddy, thanks for that battery porn! Love it!

P.S. Why did you discharge down to 2.5V/cell when ANR26650M1B's discharge cut-off voltage is 2.0V? And why did you use 10A (10A : 8 = 1.25A/cell i.e. 0.5C) for checking capacity instead of 4A (0.5A x 8).

I think 37% capacity loss is kinda unreal.

Because in real world operational scenarios most 12v equipment would not operate down in the 8v range (2vdc per cell), 10vdc is a more realistic operating range.  

Plus, when you look at the discharge curve of the battery itself, going from 2.5 to 2.0 offers VERY LITTLE in terms of additional capacity, and increases cell degradation at an expedited rate.  After 2.5v the fall off curve is STEEP, which is typical for most LiFePO4 chemistry... curves are flat until they start to roll off then dive.

Two, these are very high drain cells... capable of 70 amps discharge each.  The test preformed at 1.25a each vs 0.5a each literally makes zero difference.  In addition, these would not be used in low drain applications, higher discharge rates give a better real world use case for testing.  Higher rates are preferred so I dont have to wait around all day, and my charger is capable of doing it without an external load.

My testing methods yield pretty accurate results with this charger... 37% loss at the module / pack level is actually the better of the 12v chunks I evaluated.


How did you get the black plastic covers off the screws that connect to the BMS?  I had some packs that had rubber screw covers, and others that were a hard black plastic.  I took a dremel to them, but they're still really hard to get out.
Reply
#9
All of mine had the rubber screw covers that were very easy to remove.
Reply


Who read this thread?
70 User(s) read this thread:
Eduardo Kang (09-12-2019, 09:38 AM), fannel (05-09-2019, 08:35 PM), Satiriasis (04-26-2019, 09:17 PM), Hoschilein (05-22-2019, 08:25 AM), OffGridInTheCity (09-05-2019, 08:44 PM), kevinjaye (05-28-2019, 08:53 PM), HollandNL (05-21-2019, 05:39 PM), stevelectric (04-29-2019, 05:00 PM), Solardad (05-21-2019, 06:57 PM), xenomorph113 (05-25-2019, 12:34 AM), Lekr (05-20-2019, 09:29 PM), Bastler_Ro (05-09-2019, 06:25 PM), Wolf (09-06-2019, 05:40 PM), Shawndoe (05-10-2019, 05:48 AM), Niemma (05-24-2019, 12:49 PM), jaeger-audiodesign (04-22-2019, 04:41 PM), Legolfeur95 (04-22-2019, 05:25 PM), Overmind (05-10-2019, 06:27 AM), ma3006he (05-15-2019, 06:30 AM), Shooter_114 (09-08-2019, 12:56 AM), skpro (09-05-2019, 07:58 PM), James-w (09-05-2019, 11:08 PM), chad (09-06-2019, 02:08 AM), DeepB (08-15-2019, 08:40 AM), drnickriviera (09-13-2019, 12:26 AM), FunN4Lo (06-26-2019, 04:14 AM), jacen17 (06-27-2019, 06:37 PM), turbo6bar (05-10-2019, 02:52 PM), charlie_prospect (04-27-2019, 10:54 AM), BitcoinBandit (04-23-2019, 12:04 PM), Marrcin (05-05-2019, 06:42 PM), 100kwh-hunter (09-08-2019, 07:28 PM), Lucan (06-03-2019, 02:30 AM), winny (05-13-2019, 01:43 PM), emuland-metroman (04-26-2019, 07:26 PM), WuggyBuggy (05-21-2019, 02:54 PM), Geek (09-06-2019, 01:17 AM), Mazlem (09-09-2019, 03:20 PM), BlueSwordM (05-12-2019, 08:40 PM), Stefaan De Ridder (05-21-2019, 06:43 PM), Hanssing (09-12-2019, 08:59 AM), Jack Daniels (09-07-2019, 03:03 AM), watts-on (05-22-2019, 07:52 AM), The-J-Man (04-27-2019, 12:48 PM), jdeadman (09-06-2019, 02:34 AM), Frnandu Martiński (05-28-2019, 08:16 AM), PAF (09-06-2019, 06:06 AM), A + A (05-22-2019, 04:32 AM), Korishan (05-21-2019, 08:33 PM), 18650Shrink (05-21-2019, 02:46 PM), mike (05-21-2019, 05:49 PM), floydR (05-11-2019, 12:59 AM), Grumplestiltskin (04-29-2019, 10:24 PM), Oz18650 (09-05-2019, 11:22 PM), Katarn_89 (04-23-2019, 10:15 PM), 100fuegos (05-22-2019, 07:44 PM), Cherry67 (04-23-2019, 02:45 PM), JDish (05-29-2019, 10:32 AM), conejoblanco (05-22-2019, 05:58 AM), thunderheart (05-21-2019, 07:02 PM), Ibiza (04-22-2019, 05:43 PM), Redpacket (05-10-2019, 10:58 AM), jonyjoe505 (09-06-2019, 03:15 AM), Crimp Daddy (09-05-2019, 09:28 PM), gpn (09-06-2019, 04:01 AM), Issac (04-23-2019, 11:03 AM), spinningmagnets (05-22-2019, 02:17 AM), Charly144 (04-22-2019, 05:45 PM), CarelHassink (09-06-2019, 02:43 AM), Sean (09-05-2019, 09:22 PM)

Forum Jump:


Users browsing this thread: 1 Guest(s)