Symptoms
- Charger light doesn't turn on or blinks an error code
- Battery shows no charge after hours on the charger
- Battery drains very quickly after a full charge
- Battery feels warm even when not in use
Likely causes
- CommonDirty or corroded battery contactsDirt or oxidation on contacts prevents a good connection with the charger.
- CommonAged battery pack with degraded cellsLithium batteries lose capacity over several years of charge cycles.
- PossibleFaulty chargerThe charger itself can fail even if the battery is fine.
- PossibleBattery management system lockout from deep dischargeLetting a battery sit fully drained for a long time can trigger a protective lockout.
What to do
- Clean the battery and charger contacts with a dry cloth or contact cleaner.
- Try a different known-good outlet to rule out a power issue.
- Test with a different battery on the same charger, or the same battery on a different compatible charger, to isolate the fault.
- Check the charger's indicator light against the manual for error codes.
- If the battery has sat fully dead for a long time, try a longer charge attempt as some chargers detect and slowly recover deeply discharged cells.
- Inspect the battery casing for any swelling or damage.
- If the battery is several years old and won't hold a charge, it likely needs replacement.
Tools and parts
- Contact cleaner or dry cloth
Hedge trimmer replacement batterySearch: “cordless hedge trimmer battery”
Battery chargerSearch: “cordless tool battery charger replacement”
When to call a pro
If the battery is swollen or damaged, take it to a battery recycling center rather than a repair shop; most retailers with battery drop-off bins accept them.
Safety
Use caution
Stop using and safely dispose of any battery that is swollen, hot to the touch, or leaking; do not attempt to charge or puncture it.