Feedback about folded battery layout for 14s12p pack

pbert

1 W
Joined
May 8, 2019
Messages
59
Hi,

Im building a 14s12p pack that will be folded in half, basically built out of 2 block and connected at mid point. I've attached a pic of the best battery layout that i could think of. I tried to keep the series connections short. The pack will fold in the middle. Let me know if anyone has feedback or better ideas before i get going. Thanks.

Edited with image showing fold line and the green rectangles to show one side of the connections between the series cells.
 
Here is the result. This is going to have a BMS that can allow up to 120 Amps... anyone see any issues with the pack ? Copper sandwhich of 0.15 copper and 0.15 nickel. Used 4 AWG copper buss for the cells that had many cells distance from the next cell in order to support high current. The pack folds in the middle and i'll secure the 2 halfs together once its ready.
 

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Wow great pack! Out of curiosity why the 20S instead of 25S or 25R? Also what did you use to grind the old spot welds off?
 
thanks! i would have prefered 25R for sure but got a good deal on these used 20R cells ... that is the sad truth :) the cells were already individual, i didnt have to grind the old connections off.

If i would buy new cells to make this i would have chosen Samsung 40T, 10P14S would give 40Ah and able to deliver 300Amps continuous ...
 
spinningmagnets said:
I will be very interested to see how this goes. LFP was a fan of lower volts and the highest possible amps...

Who was LFP ?
 
pbert said:
spinningmagnets said:
I will be very interested to see how this goes. LFP was a fan of lower volts and the highest possible amps...

Who was LFP ?

Im LFP.

Current is an EV's friend when you're good at making low resistance bussing and joints. 20S makes best use of the 100Vds MOSFET Silicon die switching power density. It also lets you run at the peak of the ASI voltage acceptance (21s is sometimes stable).
 
I see Luke has responded. Luke is very busy these days, doing a lot of wonderful things in the EV world.

Years ago, he posted here a lot, but recently I think he has been working very long hours.

Let's just say that...if Luke makes a statement with confidence, I will pay attention to it, and over the years...his perspective has been proven over time.

I have over 12,000 posts, but...if Luke states that I made a mistake, I recommend that you take it seriously and research it.
 
Cool! Do you guys think this battery will hold up for 120 Amp pull ? Or you see any issues with it possibly burning to the ground ? It's going into an Electric Motion trials bike. Either way, for the first ride im going to ride it incrementally with more power. I have a smart BMS with bluetooth app for it so will be monitoring the current draw and temps in real time. Thanks.
 
So just reporting back after having tested and ridden the pack. Plugged it into an Electric Motion and went for a ride up and down a ski hill about 9 times. The amps, voltage drops and temperatures were monitored on the bluetooth bms. The pack hit the 120A continuous value a few times and the voltage drop was nice and steady. Temps were also good. We were riding for about 2 hours. I can say that this pack was a success!
 

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