One or more cells within the IQ Battery 5P have developed a fault or significant voltage imbalance compared to the rest of the pack.
Common causes
Cell degradation after extended cyclingDeep discharge event causing irreversible cell damageManufacturing defect in a cell group
What to check
STEP 1
Check Enlighten for battery State of Health and cycle count. A cell fault on a battery with high cycle count or a history of deep discharges is more likely
STEP 2
Note whether battery still charges to 100% and discharges its full rated capacity. Significant capacity loss alongside a cell fault indicates degradation
Escalate if
Cell fault with significant capacity loss or fault persisting regardless of state -- escalate for battery inspection under warranty if within 10 years
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