Hi all,
My 18-month-old Cyclamatic has started acting up again and I'd really appreciate any advice. In short the BMS on the battery seems to be shutting down due to Low Voltage Cutoff before its indicator shows a low charge.
The battery pack is a 24V 10A Li-ion. I'm fairly sure it's an LVC problem because it happens anytime the pack reaches 23.7V under load. I believe it's the BMS because even the onboard charge indicator turns off.
The result is my powered range has been reduced to 4 - 6 miles, and towards that point, forces me to stop and turn the pack off and on again constantly.
Some measurements:
At full charge (which I do after every journey) the pack shows 29.3V when idle, and dips a variable amount under load, at most down to 28.2V or so.
After around 4 miles it reaches 27.9V idle, and struggles intermittently to stay above LVC (wind gust or climb = stop and reset). At over 5 miles it shows 27.2V idle and can only handle a few seconds even on level terrain.
What might cause the pack to hit its LVC while the charge indicator is full bars? Wouldn't the BMS work around any failing/under-performing cell(s)?
Is there anything I can do to prevent it from hitting the LVC so that it might continue providing whatever amperage it's capable of (at say 27.5V?) until it's truly at low charge?
Thanks in advance!
My 18-month-old Cyclamatic has started acting up again and I'd really appreciate any advice. In short the BMS on the battery seems to be shutting down due to Low Voltage Cutoff before its indicator shows a low charge.
The battery pack is a 24V 10A Li-ion. I'm fairly sure it's an LVC problem because it happens anytime the pack reaches 23.7V under load. I believe it's the BMS because even the onboard charge indicator turns off.
The result is my powered range has been reduced to 4 - 6 miles, and towards that point, forces me to stop and turn the pack off and on again constantly.
Some measurements:
At full charge (which I do after every journey) the pack shows 29.3V when idle, and dips a variable amount under load, at most down to 28.2V or so.
After around 4 miles it reaches 27.9V idle, and struggles intermittently to stay above LVC (wind gust or climb = stop and reset). At over 5 miles it shows 27.2V idle and can only handle a few seconds even on level terrain.
What might cause the pack to hit its LVC while the charge indicator is full bars? Wouldn't the BMS work around any failing/under-performing cell(s)?
Is there anything I can do to prevent it from hitting the LVC so that it might continue providing whatever amperage it's capable of (at say 27.5V?) until it's truly at low charge?
Thanks in advance!
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