How to check power tool battery status and replace drill battery

Check a Cordless Power Tool Battery Working Status and Performance Steps

If your cordless power tool battery does not hold a charge or it runs down quickly, it may need to be replaced. Cordless drill batteries can wear out over time. The performance of the battery can also deteriorate if the battery has become damaged. Using a multimeter, cordless drill batteries can be tested to determine if they need to be replaced.

1. Plug the battery in and charge it for at least an hour. Unplug the battery when you are ready to test it.

2. Check the voltage indicator on the multimeter. A fully charged battery should test at least 1 volt higher than the voltage that is listed on the battery. For example, an 18-volt battery should test at 19 volts or higher.

3. Touch the multimeter probes to the two Dewalt DW9091 Cordless Drill Battery terminals. Be sure to touch the negative probe to the negative terminal, and the positive probe to the positive terminal.

4. If the voltage indicator is at or below the voltage rating on the battery, the battery needs to be replaced.

5. If the voltage indicator shows a high voltage, but the battery is still not holding a charge, it may need to be repaired. In that event, take the battery to a tool repair shop for more thorough testing and repair.

Replace Cordless Power Tool Batteries in the Battery Pack Instructions

A cordless drill serves many functions. It can be used to make minor fixes and repairs around the house and can also be used on a construction site. Several power tool manufacturers make different brands and models of cordless drills, all with different specifications, speeds and features. However, the drill battery packs used in the various cordless drills all remain the same. The drill battery packs contain either Ni-Cd, Ni-MH or Li-ion batteries. If the cordless drill is no longer charging or holding a charge, it may be time to replace one new drill battery.

Step 1: Remove the cordless drill from the charging station. Turn the drill off.

Step 2: Remove the battery pack. The battery pack is located on the bottom of a cordless drill and can be loosened by pressing two tabs, one on each side of the drill. Once loosened, pull the Makita 1234 Power Tool Battery Pack downward to remove it.

Step 3: Remove the power tool battery cap. It usually just slides off, but it may be held in place with a small screw, depending on the cordless drill manufacture. If there is a screw, use a small Phillips-head screwdriver to unscrew the screw and then slide off.

Step 4: Remove the old drill batteries. Place the new batteries into place.

Step 5: Place the battery cap back over the batteries. If needed, screw the screw back into place.

Step  6: Slide the battery pack back into place on the bottom of the cordless drill. You should hear a snap or pop when the battery pack is firmly in place. Allow the new batteries to charge for at least 24 hours before use.