Drill battery drains fast or doesn't last through a job

Symptoms

• Battery shows full charge but dies after a few minutes of use
• Runtime has gotten noticeably shorter over months
• Battery drains even sitting unused in the tool
• Battery feels warm after only light use

Likely causes

• CommonBattery has lost capacity with ageLithium-ion cells gradually hold less charge after repeated charge cycles, especially after 2+ years.
• CommonCold temperatures reducing usable capacityBattery chemistry is temperature sensitive and can show far less runtime below about 40°F.
• PossibleHeavy-load tasks like large bits in hardwood or masonryHigh-torque tasks draw much more current and drain a pack faster than light driving.
• PossibleBattery left in a partially charged state for long periodsStoring at very low or very high charge for months can accelerate capacity loss.
• PossibleOne weak cell inside the packA single failing cell in a multi-cell pack can cause early cutoff even if others are fine.

What to do

1. Let a cold battery warm to room temperature before use and store batteries indoors in winter.
2. Charge the battery fully and note the runtime on a simple task to compare against when it was new.
3. Avoid leaving batteries on the charger for days at a time or fully drained in storage for weeks.
4. Match the bit and task to the tool: use a lower gear and let the drill work rather than forcing large bits.
5. Rotate between two batteries if you own them, so one is always charging while the other works.
6. If runtime has dropped to a fraction of when it was new despite normal use, plan to replace the pack.

Tools and parts

When to call a pro

There's no repair for a naturally aged lithium-ion pack; if it's swollen or unusually hot, stop using it and take it to a battery recycling drop-off instead of a repair shop.

Safety