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Batteries - (Get a Charge Out of Your FSJ)

Contributed by: Joe Sego

First of all there are four basic types of automotive batteries. We're talking the lead-acid type. They are:

  • Automotive Starting- This is most common
  • Low Deep Cycle- Marine or RV
  • High Deep Cycle- Not applicable
  • Gel Cells- A possibility

Automotive starting is lead plate type. Life expectancy is 3-5 years, less than 2 years in deep cycle service. From day one particles of lead separate from the plates and slowly drop to the bottom. (more on this later)

Low deep cycle is basically a beefed up automotive starting type. Not a true deep-cycle battery. These are designed for large loads over a long period of time. Usually a 200 to 400 cycle life span.

High deep cycle batteries are prohibited for normal use by it's extreme size. A 350 amp-hour 12 volt weighs 250 pounds and holds 4 1/2 gallons of acid! They contain large lead plates and can be cycled 1000 to 2000 times.

Gel cells have a jellied electrolyte and a sealed case. They are common in aircraft since they can be mounted in any position. They have good deep cycle capabilities. However they can not be charged or discharged to quickly or they can create gas and blow the sealed case rendering them useless.

Extreme heat and cold are a battery's worst enemy. A little known fact: More batteries are purchased in the summer months than winter. Of the two evils, heat is harder on the battery than cold. Many cold weather problems are blamed on the battery when it's actually bad or corroded connections, 40 weight oil, dragging starters etc. These problems always show their ugly heads when the temp is 0.F.

"Hey don't sit that battery on the floor, it'll discharge!" How many times you heard that? WRONG. Just an old wives-tale. It was true 60 years ago when batteries were housed in wood cases. Quite impossible with today's plastic cases. A lead-acid battery will eventually discharge no matter where it sits.

CCA's. We are all familiar with Cold Cranking Amps (CCA) of a battery. Is more better? Sure. If your FSJ requires a 700 CCA battery should you buy a 700 ? Under normal conditions yes, in a FSJ, I'd say no. Why? Because so many FSJ's have "owner added" features. Such as; snow plows, winches, millions of candlepower light bars, air compressors, etc. All these devices need more amps than your stock battery can handle. It is possible to discharge a battery with the engine running and a good alternator, matter of fact I have done it! Your best bet is to go with a 1000 CCA battery or larger. The ideal situation is two batteries. Where to mount a second battery and how to hook it up is subject for another article. But if you've added many amp-robbing options you better have a strong battery(s).

Battery brands. Is one brand better than another? Probably not. If you're in the market for a 1000 CCA battery, buy the cheapest one you can. Why? Because there are only four battery manufacturers in the United States! Yea I know, but there's 127 different battery names! Well I know for a fact that all major battery warehouses apply the name to the battery just before it's delivered to the retail outlet. The warehouse has name stickers for Shell, Amoco, Marathon, Sears, etc. Go for the best deal. Forget names. Matter of fact you'll pay more for a name.

What's the difference in a 3 year battery and a 5 year? This part is great! (if you manufacture batteries) Are the plates thicker in the 5 year? No. Are the plates larger in the 5 year? No. Does it have more plates? No. So what's the difference? SPACE, that's the difference. This SPACE is the area between the bottom plate and the bottom of the battery case. That's it! The space in a 3 year battery might be 1/2 inch whereas the SPACE in a 5 year battery is 1.5 inches. When this SPACE gets full of lead plate debris, the battery is ka-put. The more SPACE you have, the longer the battery lasts. So, if you could take a 3 year battery and put it in a 5 year case you would have a 3 year battery that lasts 5 years.

Lastly, beware of a hot battery. (no not stolen) A boiling battery can and most likely will blow up! This can be lethal. Also when jump starting a wrong connection and you have a miniature bomb on your hands, or face. Always use proper jump starting procedures, this is using the engine or another metal surface for the ground or negative connection. Not at the battery post.

Joe Sego -

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