I charge 4a for my 12s8p 30q and mine stays cool as a cucumber
2 Likes
I dont really know. Ive had the pack for about a month and only had to charge a couple times
1 Like
What is āhotā for you? 
3A is below the standard charge rate so you would expect that they wouldnāt get warm enough for their cycle life to be affected too much more (versus lower current charging). But, you have your cells wrapped up in a pack and you will have to measure the temperature of any inner cells (or whichever get the warmest) to see if 3A/cell is an issue. Someone with a similar pack might have done that though.
Staying below 45Ā°C is a good target for the warmest cells.
2 Likes
Yeah if I stick it on my 3A backup charger no heat. But the 8A and its noticeable. But it is a brick so im sure thatās trapping a lot of heat in general
1 Like
And the internal temps will be a lot higher than what you feel on the outside.
Yeah, im not overly concerned. I dont think itās reaching any hotter than it is during discharge. Iāll have to measure it next time. Iām guessing 35*C in the center of the brick.
1 Like
Yup. For this reason I adjust to charge at 38 or do measured C. This also greatly depends on how the thermistor is in the pack
1 Like
2A on 10s2p Panasonic cells
2A or 5A on 10s4p 30q
2A or 7A on 12s1p lipo
1 Like
For me
12s7p 30q I charge at 6a because the charger was a good value
12s1p lipo has got a 4a charger
8s6p lipo has got only an 8s3a because I had a mixup and ordered the wrong one a while ago
Revel kit is a 10s2p 30q pack and they charge at 2.5a
1 Like
My 12s6p 30q stays cold at 9.6a
1 Like
I threw a 3 volt and 4 volt 30Q cell in parallel and barely noticed an increase in temp. I forget the cells resistance and subsequent current flow but was a lot
1 Like
I charge my 13s4p 40T pack at 10amps (15A charge port fuse). I charge it fully about twice a week.
1 Like
Interesting, from 3.2V per cell to 4.2V per cell? Also you sure of 9.6A? Seems specific so Iām guessing so. My LLT bms says 7.8A as the real amperage iirc.
Depends on the ride but it usually is 3.1 to 4.2
Ammeter said 9.62a (before CV kicks in at the end)
And my LLT also says 9.6
1 Like
interesting. build like a brick or laid out?
Brick style
Pcb 6p packs 8 on left and 4 on right (bottom right space is used for BMS and accessories battery)
2 Likes
I bought a 12S5P P42A pack from Acido and an 8A charger from Anubis. I havenāt charged it yet tho, but hopefully I will finish my build and charge it up on the weekend.
Stupid question but whatās the easiest way to measure charging current w/ a multimeter w/o a smart bms?
You have to use the meterās DC current setting, plugging the probes into correct meter positions, and place the meterās probes in series with the current flowing to the battery. That makes the charging current flow through the meter so it can display what the current level is.
Be sure you do not go over the meterās rating for DC current!
1 Like
You need a power/watt meter. Something like this guy.
Thereās a good chance your meter canāt handle charging current.
1 Like