How to Recondition Old Car Batteries

It only takes a few simple tools to recondition a battery.

People are more in tune with the green movement and are being conscious of reusing items instead of just throwing them out. Cars and their different components are no exception to this. Car batteries are a source of savings when people recondition them instead of just buying new ones. Reconditioned batteries are not a new idea--they have been sold to consumers for years. But today, you can recondition your batteries in your own garage.

Things You'll Need

• Protective eye wear
• Plastic funnel
• Battery hydrometer
• Battery post/terminal cleaner
• Screwdriver
• Voltmeter with probes
• Battery load tester
• Battery treatment (optional)
• 6/12-volt battery charger/starter

Instructions

1. Put on the safety glasses. Clean the battery posts by pushing a battery post cleaner on each battery post and turning it back and forth until the posts are bright and shiny.

2. Check the battery voltage. Place a probe from the voltmeter on the positive battery terminal and the other probe onto the negative terminal. If the meter reads less than 12 volts, there could be a problem with at least one cell.

3. Remove the cell covers. Place a screwdriver under the cell cover and gently pry it up, taking care to not spill any of the liquid. Remove the cover and place it aside.

4. Test the cells. Place a probe from the voltmeter on the positive battery post and the other probe in the first cell. If the cell does not read 2 or more volts on the meter, there is a problem with that cell. Move to the next cell and repeat this procedure, testing all cells and noting their reading.

5. Perform a load test. Connect a load tester to the positive battery terminal and then to the negative post. Doing it in this manner will prevent the cables from creating sparks. Switch the load tester to the "On" position and make sure that the load does not drop below 10 volts. If it does, the battery may not be able to be reconditioned.

6. Perform a hydrometer test. Squeeze the bulb of the hydrometer before inserting the rubber tube into a battery cell. Insert the tube into a cell and release the bulb. This will cause the battery fluid to be sucked into the tester. Note which color the fluid rises to. Green means you have a good battery. White means the battery is fair. Red means the battery needs a charge. Also, make sure that the electrolyte fluid covers the lead in each cell by at least 1/8 inch. Repeat this test on all cells. Add fluid to any low cells.

7. Add the battery treatment chemicals. Follow the chemical manufacturer's instructions on adding the chemicals. Do not spill any of the chemicals, and clean up any spills immediately. Replace the cell covers and place the battery on a charger for at least 24 hours.

Tips & Warnings

• Use a trickle charger to charge your battery. This provides the best charge for your battery. Avoid quick charges, as they damage battery cells.

• Never work on a batter while it is connected to your vehicle. It could short out your car's electrical system and ruin your vehicle's wiring.

References

• CB Electric Car: Re-condition a dead car battery
• Info Barrel: How to test and re-condition a battery