Spring is typically a good time to tune up your golf car’s batteries, especially if they have been stored away during the harsh cold months. In some locations, however, winter isn’t as bad, and many communities continue using their golf cars through the summer. But those conditions can also be extreme, depending on where you live. Either way, these maintenance steps will allow you to prepare your vehicle after winter storage and/or to prepare your batteries for storage during excessive heat conditions.
Battery Storage in Extreme Temperatures
Winter: During extreme winter storage, Flooded Lead-Acid (FLA) and Absorbed Glass Mat (AGM) batteries should be stored fully charged. Check the battery manufacturer’s recommendation for the fully charged specific gravity and open circuit voltages for each type of battery. Battery manufacturers do not recommend storing lithium batteries in extreme weather conditions. If the temperature is below 32ºF (0ºC), the battery will go into protection mode and can’t receive any charge until the battery is above 32 degrees. The U.S. Battery Essential Li® US 12V G24 lithium battery has a built-in heating element that will warm the battery and allow a receiving charge at low temperatures. Other models have it as an option, (US 24V GC2H, 48VGC2H, and US 48V 105H models designated with an H). The chargers used for batteries with heating elements require a unique configuration and communication protocol. Please check the battery manufacturers for details.
Summer: Batteries should always be stored in a fully charged state. Modern chargers are automatic and can be left connected to maintain the batteries at full charge. In climates where garage temperatures can be above 100°F for extended periods, and the batteries will be left unattended, thermal runaway can be a concern. In this case, golf car owners can use an industrial timer rated for 20-30 amps at 120 VAC (not a low-power timer for lamps or lights) can be used to limit the charge time to 1-2 hours per day. This timer will prevent any thermal runaway and will maintain the batteries at full charge until the owner returns.
Post Storage Tips To Tune-Up Batteries
1) Always perform battery maintenance in a well-ventilated area and wear eye and skin protection when maintaining batteries.
2) Check the wires and terminals connected to the batteries. If corroded, clean them with a mixture of baking soda and water to neutralize acid corrosion (easily done with a spray bottle). Remove the cables from the battery terminals and clean them using a wire brush with a plastic or wooden handle to prevent shorting. Replace any wires that are frayed or broken. Reconnect the cables and torque to 100 inch pounds or 15-18 pounds on the end of a six-inch wrench. Do not over-tighten lead terminals, as they can easily be damaged. The split-ring lock washers that should always be used flatten at ~100 inch-pounds, making them a good torque indicator when a torque wrench is not available. Once the terminals and cables are clean and connections are secure, use silicone spray or corrosion inhibitor to prevent additional corrosion from forming.
3) Check the state of charge (SOC). Many lithium batteries have a state of charge indicator (LED) on the battery top or connect to a remote display. AGM battery owners can check the SOC with a multimeter. FLA batteries can be checked with a multimeter, or, even better, the specific gravity in each cell can be checked with a battery hydrometer. Refer to the battery manufacturer’s instructions for state of charge parameters.
If the electrolyte levels of FLA batteries are low, refill with distilled or deionized water to cover the plates with at least ¼ inches of electrolyte before charging. After charging, top off to within ¼ inches of the split-ring level indicator.
4) The golf car is ready for use if the batteries are fully charged. If they are not, connect the charger and let it run through a complete charge cycle. After charging, recheck the electrolyte level of the FLA batteries and use a hydrometer to verify they are at full charge.
5) After the first 30 days of use, an equalization charge of FLA batteries should be performed to balance the cells and to mix the electrolyte to prevent stratification. For AGM batteries, check the battery manufacturer’s recommendations for equalization charging. U.S. Battery Essential Li® batteries do not require equalization charges because the BMS has a built-in cell balance function to adjust the cell differences during each charging process.
Once you’ve completed these steps, your golf car batteries should be ready to go back to work after any type of extreme-temperature storage.
