How Do You Refill a Car Battery?

Refill a standard car battery by pouring distilled water into the inlets located at top of the battery to the appropriate level. A standard car battery cannot have the water exceed past its recommended specifications as it can cause serious damage.

Batteries are usually considered maintenance-free products, but under extreme conditions, they will require inspection. Standard 12-volt car batteries have six tubes that lead to where the water is stored. The tubes themselves are short and act as a measuring tool to help determine the maximum fill line. Overfilling that water can result in acid overflow, which will damage the battery along with components found around it. The following instructions explain how to safely refill water in a battery.

  1. Disconnect the battery
  2. Disconnect the battery, removing the negative terminal first and then the positive.

  3. Locate the vent caps
  4. The vent caps are found on top of the battery. Use a flat head screwdriver to pry them off.

  5. Inspect the vents
  6. Inspect the vent wells. Check to see how much water is required to properly fill the battery back to its normal capacity.

  7. Add distilled water
  8. Pour distilled water into the battery until just under the tubes.

  9. Reconnect the battery
  10. Once finished, reconnect the battery attaching the positive terminal first and then the negative.