Cordless drills are powered by rechargeable power tools batteries. Over time these batteries lose their ability to charge fully and maintain a charge. If your battery won’t charge at all this is a simple way to get it to charge again.
If you are going to use the car battery charger be sure the two wires are not touching and plug it in. Touch the positive (red) to the positive (+) on the drill battery and touch the negative (black) to the negative (-) on the drill battery. Hold the charger on your battery for 5-10 seconds. This will give it enough of a boost to start charging again in your drill battery charger. If you don’t have a car battery charger you can repeat the above steps using jumper cables from your car battery.
1. Hold the charge to the cordless power tools battery for several seconds and take it over to it’s charger to see if it worked.
2. Never use a charger rated for more volts that your drill battery’s capacity (example: don’t put 12 volts to a 9.6v battery). You are better off using a lower volts charger or battery as not to damage the power tool battery or worse.
3. Wear safety glasses.
4. Don’t hold the charge or charger to the battery too long. If it’s going to work it will work right away.