Black and Decker designed Versapak batteries for power tools such as the cordless drill, work flashlight and rechargeable screwdriver. The batteries come in two different types: gold and silver. Versapak gold batteries last 60 per cent longer than the silver type, because they are Nickel Metal Hydride, or NiMH. Silver Versapak batteries are Nickel Cadmium or NiCd and have battery memory, which means they lose a charge faster if they are not fully discharged before recharging. Reconditioning will extend the life of a Versapak battery and increase the charge capacity.
Test your batteries with your voltmeter to determine voltage. Reconditioning a Versapak battery when it registers zero ohms or over three volts could damage it. Plug the lead wires into the voltmeter, matching red to positive and black to negative.
Switch your voltmeter to "DC" and touch the corresponding test probes to the positive and negative terminals of the battery. Note the voltage.
Place the negative wire from the 12-volt car battery to the outer plastic casing of the battery. Hold it there while tapping the positive wire to the inner part of the battery for three seconds.
Let the battery cool down for 15 minutes, then test the battery's charge with the voltmeter. If the voltage is still low, repeat the reconditioning surge. Extremely damaged battery cells may take up to 20 surges to successfully hold a charge.
Remove your batteries from the charger as soon as they are fully charged. This takes less than four hours for standard chargers. Charge batteries just before you use them for optimal performance.
Do not cross positive and negative terminals. This may result in sparks, shocks or explosions. Always wear protective gear like safety goggles when working with electricity.