Battery Myth  # 1

     You may have heard this one before. It sometimes comes in the form of a tip from someone who calls in on a radio station, then gets passed on from there. Sometimes it given by radio announcers as a tip to listeners. It goes something like "On those very cold mornings, you can help your car start by turning on the lights for a little while before starting your car. It warms up the battery and helps it start better. "

      One explanation offered is that the current flowing through the internal battery resistance generates the heat. In reality, the equivalent resistance of the battery is very low, and there just isn't enough to generate any significant heat. Since the starter may draw 20 times or more current than the headlights, if this were a significant effect, the starter would do more to warm the battery. And consider all that energy going into the headlights could be going into turning over the engine. When you run the headlights with the engine off, you are draining energy stored in the battery that otherwise could get you going.

     The best way to make sure your car will start in the cold is normal or preventative maintenance. Have your battery and electrical system checked thoroughly before the winter season arrives. That includes: 1) electrolyte level   2) connections on all battery/starter cables   3) checking the age (date code) of the battery   4) Have the battery load tested 5) Checking the alternator / charging system. See the AutoTips alternator page .

 If you are in a very cold area, you may be able to use a thinner 5w-30 weight engine oil rather than a 10w-30, or use a synthetic 10w-30 oil -- check your owner's manual.

Battery Myth #2   Storing a battery on a concrete floor will discharge the battery.

There is not currently a strong reason for avoiding contact of a battery with a concrete floor. The battery's contact with the concrete should not create a problem with the material in today' s batteries. If the battery is not clean, but has a surface layer of acid or grime which is conductive, the battery can be expected to self-discharge more rapidly than if it was clean and dry. Many years ago, the batteries were constructed with a wooden case around a glass jar with the battery in it. Any moisture on the floor could cause the wood to swell and possibly fracture the glass, causing it to leak. Shortly after the introduction of "Hard Rubber" containers, which were somewhat porous and of a less than ideal design, there was a chance of current to be conducted through the container of a high carbon content if the moist concrete floor permitted the current to find an electrical ground. These are two of the older reasons for not storing batteries on a concrete floor. There is no reference to avoiding storage on concrete floors in the Battery Service Manual published by the BCI. Their suggestion is appropriate for the current state of the art batteries built by reputable battery manufacturers. For more information on storage, see the AutoTips Battery Storage Tips page.

( Thanks to Interstate Batteries for review and contributions to this article! Check out their Battery Care page for more information.)

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