Glens carzy ebike
10 mW
- Joined
- Aug 3, 2019
- Messages
- 23
Why does my battery only charge to 54 volts when it should charge to 58 volts i have tried 3 different chargers at 58 volts
58 volt battery only charges to 54 volts
- Thread starter Glens carzy ebike
- Start date
goatman
10 MW
can you take the bms off and charge it?
you have a 14s battery?
are you sure your chargers aren't 54.6v/13s, you've tested the voltage coming out of the charger with a dmm?
if you take a digital multimeter and unplug the 15 pin connector that goes into the bms, 1 black/ground wire and 14 red wires.
on my dmm I soldered sewing needles to my test leads so I have real fine and pointy probes. put the ground probe where the black wire is and the red probe on the first red wire and write down the number it should be 3.86v(54v divided by 14s equals 3.86 I believe) check to see if each of your S groups are increasing by 3.86v for example 1s-3.86v, 2s-7.72v, 3s-11.58v, 4s-15.44v. each s- increases by 3.86v. it should be 4.2v for 14s at 58.8v. if all your series groups are about 3.86 volts id say your bms is to blame.
if you have full access to your battery you can just check the voltages on the nickelstrip.
you have a 14s battery?
are you sure your chargers aren't 54.6v/13s, you've tested the voltage coming out of the charger with a dmm?
if you take a digital multimeter and unplug the 15 pin connector that goes into the bms, 1 black/ground wire and 14 red wires.
on my dmm I soldered sewing needles to my test leads so I have real fine and pointy probes. put the ground probe where the black wire is and the red probe on the first red wire and write down the number it should be 3.86v(54v divided by 14s equals 3.86 I believe) check to see if each of your S groups are increasing by 3.86v for example 1s-3.86v, 2s-7.72v, 3s-11.58v, 4s-15.44v. each s- increases by 3.86v. it should be 4.2v for 14s at 58.8v. if all your series groups are about 3.86 volts id say your bms is to blame.
if you have full access to your battery you can just check the voltages on the nickelstrip.
dogman dan
1 PW
14s pack should charge to 58.8v. But a bms equipped 13s pack would charge to 54.6v and then the bms would stop further charging.
If you have a 14s pack, and one cell group is very low in capacity, it would fill much sooner than the others, and then the bms would shut off the charge, leaving the other cell groups undercharged.
Try charging, letting it sit half an hour for the bms to lower the voltage of the highest groups, then charge it again. Repeat if the voltage keeps coming up, until the pack is better balanced.
Or identify the high charge group, and attach a 12v light bulb to that group only to discharge it some, then put back on charge.
If you have a 14s pack, and one cell group is very low in capacity, it would fill much sooner than the others, and then the bms would shut off the charge, leaving the other cell groups undercharged.
Try charging, letting it sit half an hour for the bms to lower the voltage of the highest groups, then charge it again. Repeat if the voltage keeps coming up, until the pack is better balanced.
Or identify the high charge group, and attach a 12v light bulb to that group only to discharge it some, then put back on charge.
