How to Revitalize Your Car Battery

Without the proper maintenance, your car's battery may fail at an inopportune time.

The same electrochemical processes that produce electrical energy in a lead-acid battery also destroy the energy-making components. The acid-based electrolyte in a battery reacts with the lead battery plates, creating electricity and lead sulfate crystals. These crystals coat the battery plates, and the battery loses its energy-producing capabilities. To combat the formation of these crystals, a battery must be recharged, and the electrolyte level must be replenished by adding distilled water. By performing these small but important tasks, a car battery can be quickly revitalized to almost-new condition.

Things You'll Need

• Safety goggles
• Rubber gloves
• Lead-acid automotive battery
• Battery vent wrench
• Distilled water
• Battery trickle charger
• Digital multimeter

Instructions

1. 

   Safety first! Always use protective gear when dealing with a lead-acid battery.

   Put on the safety goggles and rubber gloves.

2. Use the battery vent wrench to loosen the battery vent caps. Inspect the electrolyte level in each battery cell. For each battery cell whose electrolyte level is low, add distilled water to that cell until the electrolyte level reaches the bottom of the "fill" line.

3. Replace and tighten the battery vent caps.

4. Attach the red multimeter probe to the positive battery terminal. Attach the black multimeter probe to the negative battery terminal. Turn the multimeter on, and set the scale to "Volts DC." Check the multimeter display. If the multimeter shows that the voltage is 12.6 volts or more, the battery is ready for use. If the multimeter shows a reading of less than 12.6 volts, proceed to the next step.

5. Attach the red (positive) battery charger lead to the positive battery terminal. Attach the black (negative) battery charger lead to the negative battery terminal.

6. Plug the battery charger into a wall outlet and turn on the charger. Allow the battery to charge for at least four hours or until the battery voltage reaches 12.6 volts DC. Turn off and unplug the battery charger. Remove the battery charger leads from the battery.

Tips & Warnings

• Check the battery every half hour while charging. If the battery begins to bubble, swell, or becomes hot to the touch, unplug the battery charger immediately and allow the battery to cool down before disconnecting the charger leads.

References

• Georgia State University: Lead-Acid Battery
• "Battery Maintenance"; Popular Mechanics; Mike Allen; Aug 2000
• Autoshop 101: Battery Service