How to Resurrect a Drill Battery
Locate the point at which the wires from the battery pack terminal run down through the silver cardboard insulator. Mark this opening before you remove the battery terminal for easier reassembly.
Unscrew the cordless drill battery case to reveal the rechargeable batteries within the case. Carefully remove the top of the cordless drill battery case. Keep the screws and the spring in a container so you can find them during reassembly.
Lift the battery cells from the battery casing. If the batteries are shrink-wrapped together, cut enough of the plastic away with scissors to reveal the top and bottoms of the battery cells.
Find the positive, or raised end, on the first battery to be reconditioned. Place the black alligator clamp from the 12-volt power source on the negative end of the battery cell, while holding the red alligator clamp to the positive end for no longer than two seconds.
Loosen and lift off the terminal piece, using needle-nose pliers. The metal band underneath the terminal piece must be insulated with electrical tape before you proceed.
Remove the silver cardboard insulation piece and place this piece aside. Remove the shrink wrap from the top and bottom of the battery cells, so the battery leads are exposed.
Put the battery into the device it operates. Batteries that produce 18 volts inevitably operate power tools and, as they are motorized, it's sensible to put the power tool into a small vice so it's held in place. Otherwise you must hold the tool during the resurrection process, which can be tedious.
Turn off the power switch once the motor stops. The battery and the tool will be quite hot, so let it cool down for 30 minutes or until it feels cool. The procedure of continuously running the power tool and the warmth generated starts to break down the nickel crystals in the cells. This lets them release more energy and enables them to retain more power once the process is complete.
Turn off the power tool once it stops operating. Leave it for a few minutes and then repeat the process. Continue to repeat the process until you find it does not operate at all. This means the battery is completely discharged; the crystals have broken down and can now retain more energy.
Remove the power tool from the vice. Remove the battery and place the battery in the charger. Turn on the charger and let it charge the battery until it indicates it's full. Be prepared to wait longer than you have done for some time. The longer it takes to charge the better the resurrection process is.
Turn off the charger once the battery is charged and remove the battery from the charger. Don't leave batteries in chargers as they can start to discharge even though they are not in use. Put your resurrected battery into the device it powers when you want to use it.
Unscrew the cordless drill battery case to reveal the rechargeable batteries within the case. Carefully remove the top of the cordless drill battery case. Keep the screws and the spring in a container so you can find them during reassembly.
Lift the battery cells from the battery casing. If the batteries are shrink-wrapped together, cut enough of the plastic away with scissors to reveal the top and bottoms of the battery cells.
Find the positive, or raised end, on the first battery to be reconditioned. Place the black alligator clamp from the 12-volt power source on the negative end of the battery cell, while holding the red alligator clamp to the positive end for no longer than two seconds.
Loosen and lift off the terminal piece, using needle-nose pliers. The metal band underneath the terminal piece must be insulated with electrical tape before you proceed.
Remove the silver cardboard insulation piece and place this piece aside. Remove the shrink wrap from the top and bottom of the battery cells, so the battery leads are exposed.
Put the battery into the device it operates. Batteries that produce 18 volts inevitably operate power tools and, as they are motorized, it's sensible to put the power tool into a small vice so it's held in place. Otherwise you must hold the tool during the resurrection process, which can be tedious.
Turn off the power switch once the motor stops. The battery and the tool will be quite hot, so let it cool down for 30 minutes or until it feels cool. The procedure of continuously running the power tool and the warmth generated starts to break down the nickel crystals in the cells. This lets them release more energy and enables them to retain more power once the process is complete.
Turn off the power tool once it stops operating. Leave it for a few minutes and then repeat the process. Continue to repeat the process until you find it does not operate at all. This means the battery is completely discharged; the crystals have broken down and can now retain more energy.
Remove the power tool from the vice. Remove the battery and place the battery in the charger. Turn on the charger and let it charge the battery until it indicates it's full. Be prepared to wait longer than you have done for some time. The longer it takes to charge the better the resurrection process is.
Turn off the charger once the battery is charged and remove the battery from the charger. Don't leave batteries in chargers as they can start to discharge even though they are not in use. Put your resurrected battery into the device it powers when you want to use it.
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