A golf cart battery is the same lead-acid battery used in cars, only smaller. Most run on a six-volt lead acid cell core. If the battery dies, it is probably because the lead cells are covered in sulfur, which occurs when the battery power is overdrawn. You can restore it by flushing out the acid and cleaning the lead cells with distilled water or a solution of Epsom salts and water. This will clean the cells and allow the chemical reaction that creates electricity to occur once again.
Difficulty: Moderately Challenging
First, remove the battery cables by detaching them with a screwdriver or pliers.
Put on protective gloves and a face mask. Then remove the cell caps (small covers on the battery) and carefully drain away the acid solution for re-use later.
Pour a solution of distilled water and Epsom salts into the battery and then flush the solution. Refill again and flush the solution once more. Then pour the acid solution back into the battery, using a funnel. Place the covers back on the battery.
Hook the battery up to a charging station and fully charge the battery at 2.30 volts per cell.
Once charged, let the battery sit for a full 24 hours or longer, and test. If it is not at full capacity, apply another charge to the battery, which is called a top charge. Use the same battery charging station and put a full charge on the battery at 2.30 volts per cell.
Another method is to apply an equalizing charge, which is a stepped-up charge on the battery. Increase the charge voltage on the battery to 2.40 volts or by 100 mV and complete a full charge. This method may restore the battery without the hassle of draining and filling the water from the case.