How to Fill a Car Battery

Lead-acid batteries are the most common type of battery used in a car and were first developed more than 150 years ago. The lead-acid batteries have improved considerably over time and most new car batteries are sealed units and do not require maintenance. Older car batteries require regular maintenance, as the acid level in each of the battery's cells slowly reduces and needs filling up with distilled water. Filling a car battery with distilled water is a simple task.

Things You'll Need

  • Distilled water
  • Flat-head screwdriver
  • Remove the caps from each cell of your car battery. Some caps twist off, others require unscrewing with a screwdriver. Newer car batteries have pressure plugs. Simply insert a flat-head screwdriver under the plug and gently loosen and remove. Regular car batteries have six cells.

  • Check the fluid level of each cell. You will see a maximum fill indicator. If the fluid level is below the fill indicator, then you need to add distilled water.

  • Pour distilled water carefully into each cell until the fluid level reaches the maximum fill indicator. Do not overfill.

  • Screw or push the battery caps back onto each cell to complete the task.