· Matt Rogers

Electric Golf Car Battery Maintenance


A short check-list of how to take care of your electric golf car and its batteries, prepared by RMI Golf Carts, Olathe, Kansas.

Batteries: “RMI’s Rules of Battery Maintenance”

Rule #1: “Keep’ em Clean”  Keep the top of the battery cases clean and dry.  Sprinkle some baking soda on the cases and rinse them off when dirty with hose water; clean the green corrosion off the battery posts and cables with a wire brush whenever corrosion starts to form.  Treat the posts with spray terminal protector, not “AXLE GREASE”. 

Battery Cables:  It is very important to remove corrosion and keep the cable connections tight and a clean terminal with a tight connection is critical to the efficient and safe operation of your golf cart.  You should check the battery cable connections on the top of the batteries each month when you water your batteries.  Remove any corrosion, replace any damaged cables, and tighten the nuts on the cable terminals.

Rule #2: “Keep’ em Watered”   Although they need significantly less maintenance than automobiles, golf carts still require a certain amount of upkeep.  You may not realize it, but your golf cart batteries require maintenance throughout their life to keep them running reliably.  One integral aspect of this maintenance is battery watering. Unless you have a sealed battery, you should check the water level of your battery at regular intervals, usually about once a month, to ensure it is within the recommended range.  DO NOT let the electrolyte level fall below the top of the “plates” inside the cell!

Use distilled or reverse-osmosis filtered water if at all possible, to remove harmful minerals from the water you put into the batteries.  Using non-distilled water results in a buildup of minerals in the batteries that can negatively affect performance and lifespan.  Do your final water level check after the batteries are charged, and only fill to 1/8” below the bottom of the neck of the filler cap opening.  Over-filling causes the electrolyte to be ejected through the battery caps on to the top of the battery case. Throughout their lives, electric vehicle batteries may use up to a full 16 quarts of water.  Also, to avoid corrosion keep the plates from being exposed to the air.  For best results, clean all vent caps before replacing them.  Be sure they are tightly secured into place.  Under normal conditions you will never need to add acid. 

Rule #3: “Don’t let em Freeze”   This means keeping the batteries charged.  A fully-charged set won’t freeze until the temp falls to -92F.  A discharged set will freeze at 19F above.  The best care for an electric golf car is to play at least one round of golf every month.  If you cannot take your golf car out in the winter, check you charger every 30 days for a “green light”, and force a charge cycle by unplugging the charger from the car and plugging it back in.  Make sure your “run-tow switch” is on tow whenever the car is not in use. 

Charging Frequency:  “Charge your car Three Times!”  With modern fully-automatic chargers, your batteries like to be charged, and there is little danger of over-charging your batteries.  Charge your electric car three times:  “SOON, OFTEN… and at EVERY OPPORTUNITY!”  Lead-acid batteries do NOT have a “memory!”.  When you get a chance, “double charge” your batteries – run a second charge cycle before using your car.  Manufacturers call it “equalization charging,” and it forces a full charge on every cell. (Normally the charger shuts down when the battery pack meets specifications, and one or more cells are left under-charged).  If you can “equalize” once every month, you are “getting it done!” 

Undercharging – Leaving the golf car inactive for over 2 months will reduce the battery life.  Continually operating the battery in a partial state of charge, or storing the battery in a discharged state result in the formation of lead sulfate compounds on the plates.  Sulfating reduces the battery’s performance and may cause premature battery failure.

Under-Watering – In a deep cycle lead acid battery, water is lost during the charging process.  If the electrolyte (water/acid) level drops below the top of the plates, irreparable damage may occur, as the plates will get hot, warp and crack leaving the battery weak and inefficient.  Water levels should be checked and maintained routinely. 

Over-Watering - Excessive watering of a battery results in dilution of the electrolyte, overflow, reduced battery performance, and unnecessary maintenance which may be messy and damage the floor.

New Batteries: “Season” with care! – New batteries like to be “seasoned” if possible.  If you can, just play nine holes before charging.  Repeat for several days.  (We know this will be a hardship)  And then play no more than 18 before charging, for as many times as possible.  Always charge your batteries after play.  The batteries will get better and better “run time” capacity for the first 50-100 charge cycles.  Finally, remember to bring your golf car in at least every two years for a “discharge test”, which will often detect a faulty battery before you have to replace the full battery set.