kudos wrote:I bought two of these packs one year ago.
One of them now has a weak cell and the other has puffed already, and that's with light use.
A bit miffed actually because I was about to buy a couple more but now I'm not sure....
Yeah, if anyone else wonders - little over a year and I have had the same, 6th cell on my 2 packs is now Low voltage with one being drastically so. After my standard commute all cells nice at about 3.7 ish but then 6th cell will be about .04 lower on the bad pack it was as 3.0 yesterday (.7 lower)
I have no bms but would balance from time to time, usually monthly, never any cells abnormal until about a month ago when I balanced and end cells were low, TBH I had been lazy at this stage and hadn't balanced for 2 months.
I got around 200 charge cycles typically DoD would be ~ 85% 15A draw, in the last few months they also started being warm at the end of my 45 min commute, and one is a bit puffy now.
Always charged to 50.2 v rather than 100% @ 50.4 mostly only charged night before use, but alas the life span was terrible even though I though I took good care.
Think I need a proper battery pack this time... or do I go 3 x 4s of these again, which are on special right now ( they are just so cheap $220 delivered from local warehouse). The pain of just replacing single cells is unlikely to be worth the annoying soldering job...
- Hasa CR-9
, rear XD 2 speed
hub with disc, HK 16Ah 12s LiPo Li-Co, 11/48 gearing
Old Bike -26" MB BMSB 12aH 36v LifePo4, rear 350w 11/48 gearing
Daily commute of 36km, I also pedal sparingly due to knee concerns, so pretty FOT all the time, with light pedaling or heavier on hills...