The AIO BMS has reported significant voltage spread between cells in the battery pack.
Common causes
Normal aging causing cells to driftMissing full charge cycles (batteries kept at partial SOC)One cell degrading faster than others
What to check
STEP 1
Allow the battery to complete a full charge/discharge cycle — this allows passive balancing to run at high SOC. Balancing only occurs when cells are above 90% SOC
STEP 2
Check if the battery firmware is up to date via Fox Cloud. Check if there is a pattern of never reaching 100% SOC (time-of-use schedule preventing full charge)
Escalate if
Imbalance persists after several full charge cycles — possible cell degradation, escalate with Fox Cloud SOC history
Need full interactive diagnosis?
Faultpath walks you through decision trees, fault codes, and commissioning — built for solar & battery engineers.