As the dark hours of the day keep growing, the car battery becomes increasingly important, because it needs to start a cold engine in the morning.
Few car batteries still require maintenance. They are the old-fashioned, acid-filled type with a number of round caps at the top. To keep one of those in good condition, clean the area around each cap with a rag and carefully remove the cap.
Gloves and eye protection are a good idea because the battery contains sulfuric acid, which burns skin and eyes badly. If the lead cells are visible in the holes, distilled water needs to be added until those cells are just covered by fluid. There’s no need to add acid, but tap water also shouldn’t be used.
A battery getting a “pot belly” shape is reaching the end of its life. Likewise, if its body is transparent and you can see white crusts forming inside, a trip to the car parts dealer will be in order soon.
You can avoid paying a core charge by returning the old battery, which is the industry’s method of preventing pollution of the landscape by old batteries. Some recycling centers also pay good money for used batteries, if you have several of them piled up.
The best batteries for cars currently are the absorbed glass mat type, or AGM. They are completely sealed, maintenance-free and tend to live longer than the standard ones.
Another advantage is that some of them are deep-cycle batteries. This becomes important if you put them to heavy use, which occasionally can drain them completely. A deep-cycle type will charge right up again, whereas a standard battery may suffer after being run down.
To extend the life span of any car battery, a trickle charger is a good investment. The cheapest ones keep sending current into the cells, which isn’t advisable. I have “cooked” a few motorcycle batteries to death with cheap chargers until I switched to the type that turns itself off when a full charge is reached.
When subfreezing temperatures are in the forecast, it doesn’t hurt to put a charger under the hood and keep the battery plugged in overnight. It’ll make for a happier start-up in the morning.
Finally, when purchasing a new unit, be sure to buy the same or more “Ah” (ampere hours), which is an indication of the cranking power of the battery.
Rudi Kiefer, Ph.D., is a professor of physical science and director of sustainability at Brenau University. His column appears Sundays and at gainesvilletimes.com.