Charging your golf car’s batteries can be one of the more neglected aspects of keeping your batteries at peak performance. Even though you diligently charge your batteries every time they need to be, it may not be enough to keep them at their highest level of performance. Aside from simply charging the batteries when they get low in power, there are other variables that should be considered, starting with the type of battery technology, which changes how long, and when they are charged.
Flooded Lead-Acid (FLA), AGM, or Lithium-ion batteries require different charging algorithms that control the time, current, and amount of amperage needed. In the same way different battery designs vary in capacity and performance, charging the battery with the correct algorithm can also be as unique as the battery itself. Charging algorithms consider how the batteries are discharged, maintained, and the work environment they are used in, all variables to provide the optimum charging profile.
LEAD-ACID BATTERY CHARGING
Most lead-acid golf car battery chargers recharge the Flooded Lead Acid (FLA) batteries in three stages. The first is a Bulk Charge, where it uses constant current at full charger output to return the battery to approximately 80 percent state of charge. The second stage is an Absorption Charge, where the charger uses constant voltage to return approximately 100 percent of the ampere-hours removed during the previous discharge. In the absorption charge stage, the charger allows the battery to determine the charge rate. The third stage is the Finish Charge, where the charger uses a lower constant current to deliver a controlled overcharge, usually determined by the condition of the battery. This controlled overcharge is used to overcome charging inefficiencies, to balance all cells in the battery pack, and to assure enough gassing to properly mix the electrolyte and prevent electrolyte stratification.
AGM batteries have a design with limited acid quantity inside battery and is required to minimize the water loss (via gassing) to extend service life. Typically, there is no Finish Charge stage in the charging algorithms for AGM battery.
Lead-acid battery chargers have a switch for FLA or AGM style batteries, which offer the right algorithms to provide different amp-hour rates and voltages designed for each of these types of batteries. This prevents damaging the batteries and provides optimum charge cycle times and voltages, which can extend
service life.
LEAD-ACID CHARGING CHECKLIST
– Charge FLA and AGM batteries in a well-ventilated area.
– Always charge FLA and AGM batteries as soon as possible after discharging, and charge at every opportunity after use to limit the depth of discharge (DOD) and increase cycle life. Battery manufacturers recommend maintaining DOD to 50% or less for optimum life.
– Always use a properly sized charger with the proper charge algorithm for the battery being charged.
– Always fully charge batteries before storing for periods longer than one month.
– Check electrolyte levels monthly on FLA batteries, and fill them with distilled or deionized water to cover the plates before charging, but don’t fully top up electrolyte levels until after charging.
– Perform an equalization charge at least once a month to balance the cells connected in series to prevent sulfation and to provide sufficient gassing to fully mix the electrolyte to prevent electrolyte stratification.
LITHIUM-ION BATTERY CHARGERS
Due to their different chemistries (NMC or LFP), Lithium-ion chargers need to have the dedicated charging algorithms for different chemistries. Also, the battery management system (BMS) of a lithium battery monitors and manages the charging process. It is highly recommended to consult with battery manufacturers and find the correct charger for your lithium-ion battery. The charging process is much faster for Li batteries, but the battery management system (BMS) will determine the rate, voltage needed, and to prevent overheating or potential risks.
LITHIUM BATTERY CHARGING CHECKLIST
– Consult the battery manufacturer to make sure your battery charger is designed for their Li deep-cycle batteries.
– If using more than one Li battery in your golf car, make sure they are connected via a CAN-network bus. This allows the batteries to communicate with each other and thus, the battery charger to determine state of charge, any faults, voltage, etc.
– Li batteries can be opportunity-charged, but a full-charge cycle is necessary to provide accurate calculation on SOC, SOH etc.
Ultimately, the best way to get the most out of your batteries and your charger is to consult with the battery manufacturer and look up the charge profile they have for your specific battery. The battery charger should have that specific charge profile, allowing you to get the most out of your batteries and ultimately your equipment. For more information, visit www.usbattery.com.
