CHECKING THE BATTERY CONDITION
Take a look at the battery installation and exterior condition as part of the weekly underbonnet check Visual checks This is the easiest check and should be carried out regularly. Examine the battery case for cracks or leaks, and confirm the battery is securely mounted to prevent it moving around. Inspect the terminals for corrosion, and the security and tightness of the battery connections.
Cleaning Ensure the battery case is clean, particularly over the top and around the terminals. Keeping the case clean will actually reduce self-discharge. Remove the terminal clamps and clean them and the battery terminals with a wire brush. All contact faces should be clean and bright. If corrosion is excessive, remove the battery and clean the whole thing with a mixture of water and baking soda.
Clamps and connections Check the battery remains securely held and clamped down so that it will not move around as vehicle motion takes place. Confirm the terminal connections are tight and secure and cannot be contacted by other metallic objects.
Topping-up On older lead-acid batteries with access to the individual cells, you can check that the electrolyte level is correct. Do this when the battery is charged and in good working order. The electrolyte should just cover the cells, but no more. If not, top up the cell using distilled water only, no acid. Don’t use tap water as this contains impurities that will damage the battery plates.