Stop using it immediately. A hot battery with short run time is a primary warning sign. Here's your action list:
- Cause: Damaged battery, overcharging, or short circuit.
- Fix: Let it cool down completely away from flammable materials. Do not charge a hot battery. Inspect for physical damage—dents, cracks, leaks.
- Check the terminals. Ensure nothing conductive (metal scraps, coins) is bridging them.
- Use only the specified Makita BL18 series batteries (BL1815N, BL1820B, etc.). Non-genuine or altered batteries can burst, causing fires.
IF THAT DIDN'T WORK: The battery is likely defective. Do not use a damaged battery. Dispose of it following your local regulations—do not incinerate it, as it can explode in a fire.
HEADS UP: Charge batteries at room temperature (10°C - 40°C / 50°F - 104°F). Never recharge a fully charged battery, as overcharging shortens its life.