Shortcircuit
1 mW
I have 60v 30ah battery ( NMC ) ( 2.9AH each cell) . For charging I used a 71.4V / 5A charger . But now it wasn't working . Can I use 84v/10a charger ? Is it ok ? Or will damage the battery?
Using a high rating charger
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stan.distortion
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Would it be ok to bring the voltage down with diodes in a case like this? I'm kind of in the same situation with a 10a 84v charger and an 18s2p lipo pack( 6x 5ah 6s packs), using a hobby balance charger to charge each pack individually at the mo but it's a full day job and I have a dozen 30a bridge rectifiers to hand.
You could drop the voltage using diodes, but they will get really hot and need a huge heat sink. For just a few amps, it's not too bad.
Unless your charger is fully potted, you should be able to adjust the voltage. Many times there is a trimmer pot on the board that allows some range of adjustment. Some are fixed, but there is always going to be a resistor somewhere that can be changed to lower the voltage.
Unless your charger is fully potted, you should be able to adjust the voltage. Many times there is a trimmer pot on the board that allows some range of adjustment. Some are fixed, but there is always going to be a resistor somewhere that can be changed to lower the voltage.
stan.distortion
1 kW
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- Jun 12, 2019
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fechter said:
Thanks
I've used that voltage drop before in small circuits but was very wary of trying it on a battery pack in case I was missing something stupid, the voltages creep up and equalise after a time or something along those lines. I had a look for a trimmer on that charger but don't see any and working out where the relevant resistors are could be beyond me, will start a thread or find one on the same when it comes to getting that job doneThanks again :thumb:
You really are better off with a proper charger - designed to self terminate the charge cycle based on some kind of "smarts" judging the pack is Full
or use a separate HVC circuit that isolates the source's input.
If that HVC is adjustable, then a dumb PSU or converter will do
so long as it's hard coded not much higher than the maximum specified voltage for that pack.
Then, if you have a BMS, that can act as your redundant failsafe HVC set a little higher, in case the other regulatory circuitry fails.
or use a separate HVC circuit that isolates the source's input.
If that HVC is adjustable, then a dumb PSU or converter will do
so long as it's hard coded not much higher than the maximum specified voltage for that pack.
Then, if you have a BMS, that can act as your redundant failsafe HVC set a little higher, in case the other regulatory circuitry fails.
Shortcircuit
1 mW
fatty said:
Does the BMS protect the battery?
Shortcircuit
1 mW
john61ct said:
Even with the BMS ????
Bg-electric-cycle
10 W
Post a picture of your charger, many have a small blue pot inside and are able to dial down the voltage and charge current.
