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By Dave Erb, former editor of Old Abe’s News
 It is unfortunate that we need batteries, but we do. We need them because we are lazy, and not too patient. If you doubt what I’ve just said, find a 2N Ford tractor that is still original. It will have no battery, starter or battery ignition. In place of these parts you will find a hand crank sticking out of the grill with a magneto as the source of engine ignition. None of us like that arrangement! No matter how long our old tractors sit, we expect them to fire right up.
But once your tractor engine is started, you no longer need that heavy, clumsy battery. The charging system supplies electricity for the ignition and other needs. You wouldn’t need to drag the battery around with you except that you might want to start your engine again. So you also need a charging system so it will work again next time you need it.
How Batteries Work
Batteries are made of positive and negative plates, each connected to a post. So they don’t touch each other, wood or paper separators make a large Dagwood sandwich: positive plate, separator, negative plate, separator, positive plate, separator and so on.
This arrangement of plates and separators are suspended inside a waterproof case made of rubber or plastic with a mixture of sulfuric acid and water. Because acid can be harmful, a battery allowed to rattle around freely on its support, loose and wobbling, will have a much shorter life.
Install it Correctly
 Batteries do not like shock or vibration. Avoid a metal hold-down when you can find a better alternative. The original Ford battery hold down (a metal frame with a pair of J bolts) is fine if you want to be original, but metal close to lead acid batteries is a recipe for corrosion due to battery out-gassing during charging.
A much better method is to use a side clamp arrangement like you see on nearly every car/truck made in the past forty years or a pair of rubber bungee cords. This system has been in use on lawn mowing equipment and other industrial applications with good success. I’m not talking about WalMart multi-colored ninty-nine cent stuff here. If you use bungees, I recommend that you buy new heavy duty rubber cords, and use them in pairs.
Battery Chemistry
What we need to know about battery chemistry can be divided into two issues: how they react when they are charged, and how they wear out. Batteries wear out because the plates inside the cells begin to disintegrate, and literally fall apart. The thin lead plates begin to wear out chemically and start to crystallize, until the lead actually falls off the grids, and goes down into the bottom of the case. [Crystals on a sulfated battery can be seen in this microscope image at right. -Ed.]
This process is called sulfation. It is a normal chemical reaction of the plates and the electrolyte. Simply put, recharging causes sulfation.Worn out, disintegrated battery plates that crumble in your fingers like wet crackers will no longer take a charge or crank an engine.
When I taught classes on this subject in the industry, college and even high school, we usually began the course by taking an old battery apart to see what was inside. We’d put an old battery on the floor near a floor drain and using a hammer and screwdriver and bust it apart to see what was inside. After seeing the inside of a few worn out batteries, you get a pretty good understanding of what goes wrong when they die.
Making Batteries Last
What makes batteries last? It depends. Once the engine is started the battery is not really needed. So the less cranking a battery must do, the less recharging is needed, and the longer the battery will live. But an engine with a poorly maintained ignition and/or fuel system, or if compression is low or the ignition system needs maintenance, will run only when coaxed and that means a lot of cranking – a deep discharge followed by long recharging. This is the best recipe for short battery life.
There are really two causes of battery sulfation, recharging and elapsed time. Many of us use our tractors only occasionally. While they are sitting unused, time is marching on as your battery is sulfating. Think of it like a watch that is ticking away, chemically. Sulfation is irreversible: it always gets worse – never better. And from the moment electrolyte is poured into your new battery, a small amount of sulfation begins. That two-year-old battery you just bought has may have only a year or so left in its useful life.
Last, heat kills battery chemistry. Sulfation occur more rapidly, thus shortening battery life. Both Deka and Exide battery manufacturers report that more batteries are sold in hot climates than in cold. Some automakers have moved their battery location away from under the hood. Large trucks usually have batteries mounted along the frame rails behind the cab. And modern tractors also reflect this thinking in battery placement. But unfortunately there is no cool place on most older tractors to mount batteries.
Next up: maintenance considerations.
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Have you ever hooked up the cables wrong when jumping a battery? Hopefully the battery did not blow up in the process. Mr. Erb's advice to color the negative terminal red encourages such a scenario. Conventionally, red is positive and black is negative. Jumper cables are similarly coded. When jumpering any vehicle, it does not matter if they are positive or negative ground, always connect positive to positive and negative to negative. If jumpering 12 volt to 6 volt, the best way is to go direct to the starter, provided the 6 volt battery has enough juice to power the ignition. Otherwise, connect the negative jumper cable to the starter, and ground the positive cable away from the battery AFTER you push the starter button. This will limit the voltage to the battery.