Electric bicycle BMS failures usually occurs in the following situations:
- Overloading of a component – sometimes due to excessive current flow
- Poor soldering (not actually a BMS failure)
- Broken connectors
A frequent issue with a battery management system is the activation of its overcurrent protection. Most BMSs have solid-state circuit breakers and/or fuses. They will be triggered if there is too much current.
One of the most common situations for a BMS overcurrent protector to trigger is charging a battery after it has been fully discharged. This may generate enough current to trigger the circuit breaker.
Another situation is if one of the cells within the battery fails. This can happen but is usually uncommon unless the cells are of low quality, or the battery has been in use for a long time/lots of charge cycles.
MORE: How can I fix a faulty BMS or replace it with a high-quality BMS while avoiding the disassembly of all battery cells?