Cool, thanks Mooch. Sounds like i have to weight the dollars vs slight performance gain. Appreciate your feedback
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Thatâs easyâŚrun the hell out of at least four of each cell and compare performance every hundred cycles. 
They just need to be wrapped like a pack would (to trap the heat) and charged and discharged hard enough to bring the temps up.
They donât need to be pulsed or to simulate the different current draws when used in a board. Any discharge over a few milliseconds long is just more of the same for a cell. Continuous discharge testing will come within a couple percent of what would happen if pulse discharged. The best cells identified using continuous discharges would be the best cells identified using a simulation of âtypicalâ board use.
Only if the cells were performing to within a couple percent of each other could the results change for continuous vs pulse/variable discharge testing. But if they are performing that close then itâs very hard for anyone to notice the performance difference anyway.
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Hold up, is this Mr Battery Mooch from the YouTubes?
Welcome, thanks for visiting and commenting in detail 
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damn that soda looks good.
edit:
I just stole some of my roommates fanta that shit looked so good.
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Most people build packs with at least 4 cells in parallel and I may be wrong but we (except for Dr @Arzamenable) rarely draw more than 80a. Am I wrong to think that i wouldnât know the difference between the P42a and the 40T?
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I donât recall the last time I went for a ride and drew less than 80A 
. At least max amps
Avg be nice and low tho 
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I am not gonna add the names of all the 4WD speed demons in that postâŚ
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I donât even know you need to be a speed demon (although itâs way more fun). But just AWD will really test that battâŚ
Pro tip, make sure itâs built well 
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yep
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No, you are not wrong. Thatâs what I was saying in my post.
You probably wouldnât notice. IMO, any perceived difference in performance from ride to ride would be due to a large number of variables other than small differences in cell performance alone.
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So is it safe to say 25A would be the recommended battery amp settings for P42A? For esk8s context of course.
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It depends on how hot they get in your pack, how theyâre charged, the cycle life you want, etc.
25A-30A is about a far as I would recommend taking them for okay cycle life as long as they are not stressed otherwise.
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Uummm so Iâm totally abusing cells VTC5A 3P I regally do 3seconds burst of 80-90A in a followed by a minit of 15A pulses. I always thought that 3 second burst had time to recover
Do you have the rest of that image that isnât cropped off? 
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The fast charge rate is shown in my table.
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We have to define ârecoverâ.
Do you mean come back to its pre-burst resting voltage? That takes up to hours.
Do you mean come back to room temperature? That can take the better part of an hour.
While the internal hot spots cool down a lot in a short amount of time, and the voltage rises back up a lot of the way soon, we have to accept that we abuse the hell out of these cells and the cycle life takes a hit because of that.
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Great. Ty
30min charge times incoming 
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Mooch is here!
I always look up his bench testing results for real work expectations for cell performance.
Appreciate you joining and contributing here!
the 12S4P p42A pack Iâm building for the bustin sportster will likely get set around 20amp/cell continuous. 80A battery is more than enough. Max Ill set it is 120 amp or 30/cell.
Dont run these at 45 amp or close- its really not necessary. For 4AH 21700 cells, its still essentially in a class of its own for 20-30 amp discharge without the thermal issues. While it and the 40T can both handle 25amps, the p42a should do it a few degrees cooler
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