Most golf carts are equipped with 6-volt lead-acid batteries, which are small versions of car batteries. However, batteries in golf carts often don't last as long as they could because of neglect and improper storage. You can do several things to make a golf cart battery last longer, including reconditioning the batteries. You also can reduce problems by making sure all electrical devices on the cart are turned off when it is not in use.
Use a charger designed for lead-acid batteries that has the capability of automatically switching to low (trickle) charge when the battery is fully charged. A low-power 6-volt solar battery charger also works well. Charge the battery whenever it may be depleted or won't be used for several days or weeks.
Remove a golf cart battery to charge it, using a crescent wrench to loosen the battery cables. Use a mixture of water and baking soda to clean any deposits around the battery terminals and cables. If it is not a sealed battery, remove the cell caps and top them off with distilled water. Do not use tap water because it contains chemicals that will damage the battery and shorten its life. Turn the charger off while you connect the power leads (make sure positive is connected to positive and negative to negative). Set the charger according to manufacturer's instructions and turn it on. When charging is complete, turn the charger off, remove the battery, and reinstall it in the golf cart unless you are going to store it.
Store a golf cart battery properly. Although lead-acid batteries hold a charge well, they will drain if they sit on a shelf long enough, resulting in a deep discharge. You can leave the golf cart battery connected to a regular charger set on trickle charge or use a small solar-power charger. If using a trickle charger isn't feasible, charge the battery every couple of weeks.
Recondition lead-acid golf cart batteries to extend their useful life. Even with proper maintenance, the lead plates in a golf cart battery may become sulfated. This is relatively easy to remedy. Remove the battery as you would to charge it. Before charging, drain the fluid from the battery and replace it with a mixture of 12 per cent to 15 per cent magnesium sulphate (Epsom salts) and distilled water. Then recharge the battery. It should resume normal function, though you may have to recharge it a couple of times to bring it back to full storage capacity. Note that because the lead pates can suffer damage from the sulfation, reconditioning a battery won't work more than a few times.
When charging a lead-acid battery, wear eye protection and gloves. The sulphuric acid is extremely corrosive and can cause serious chemical burns. Avoid completely discharging a golf cart battery. Doing so causes sulfation, a process in which the sulphur in the electrolyte collects on the lead plates inside the battery, blocking the flow of electricity. In addition, sulfation corrodes the lead plates. Most lead-acid batteries are good for about 10 "deep discharges" before they are ruined. Deep discharges most often result from long periods of disuse or accidentally leaving electrical devices on the golf cart on when the cart isn't running. Make sure the cart is fully charged before each extended use.