Zeee Premium Series 3S Lipo Battery 15000mAh 11.1V 100C Soft Case RC Battery EC5 Connector with Metal Plates for RC Car Truck Tank Racing Hobby Models https://a.co/d/dEiFI8T
I’m butthurt bc some lipo manufacturers give reasonable specs.
15ah, but 13ah real world? Ok. 100c marketing, 50c IRL? That’s life.
These packs act like 10c or less cells. My 3 year old tattu 12s 14ah packs rated at 25c have better discharge curves than this and they have seen some shit and worse.
I wish RC car basher bros with turnkey manufactured toys would wake up and record telemetry and protest. I doubt the RC helicopter folks would tolerate this. And of course they don’t. Zeee doesn’t make lipos for quads, heli, or fixed wing. I should have known better.
100C is mighty big, I use 75C known good lipos for welding. I imagine this is the same bullshit as the one million lumen flashlights on Amazon. Those usually deliver 1% - 5% of their rating, these ones are probably the same.
Fair, but If you see a 1kwh cellphone charger that is human centric ergonomical design that fits in my back pocket, I also need that. I know they exist, I saw a listing on alibaba once.
100C is preposterous, that’s 1,500A in this case. That’s far, FAR beyond the fusing current level (where the copper literally melts) for the cell tabs and wiring.
Even 10C, that’s 150A current, is probably too high a rating. Certainly for continuous use and even for just pulsing the sag is too high IMO for a 10C rating.
Many companies seem to confuse “rating” with “capability”. If they can discharge it for a few seconds without the cell exploding they call that a rating. Voltage sag and cell life aren’t considered.
Yeah, I agree with Mooch. Something like ~5C continuous maybe, and 10C burst would be my back-of-the-napkin guesstimation.
Even the best LiPo batteries don’t actually ever achieve a 100C discharge output for more than a fraction of a second, if they went any longer than that they would self-immolate.
I wanted to leave it at a voltage where it would be fine to leave it sitting for a while so it’s @ 45.3 v . (I think 3.7v is a good storage voltage, but please lmk if I’m off about that). The delta is .006v at this SOC.
The cells are P42a from 18650batterystore, and were sitting at 3.5v for about 2 month is prior to this.
Personally, I feel that anything between about 3.3V (near the 30% SOC manufacturers ship cells at) and 3.7V is fine, even 3.8V. I typically use around 3.35V-3.55V, with the cells all over the place in voltage (it doesn’t matter).
The lower the voltage the longer the slower the “calendar” aging of the cell (aging over time, whether used or not) but the more aware we have to be of never letting the cells self-discharge down below 2.5V. Cells should be checked every month or so until we know that none have a high self-discharge rate.
3.0V makes a nice threshold for recharge back up to the storage voltage IMO.
Could someone tell me how much imbalance is acceptable between series group when welding?
I’ve got a pack were I made the parallel pack (will be a 10s4p) a while ago and they drifted a bit, now I have between 0.03V and 0.05V imbalance between s-packs…
Do you think the BMS will handle that? Should I lower the balance voltage on it so it matches the actual voltage of the most charged p-pack?
Or just weld them, and charge them up so the BMS balances them at full charge?
It’s an LLT smart BMS
I removed cells from NESE modules with plans to rebuild using nickel strips. As long as I keep the p group cells together, is it necessary to test capacity and IR before rebuilding?
If you don’t/didn’t have any suspicions about the cells, then I wouldn’t say it’s necessary. If you were having performance issues with the cells, it might be a good idea. All up to your own risk tolerance.
Or if you got an older phone which charges at 5V, 200A. 
