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Extract from March's Octagon Car Club Bulletin

Battery Care

Batteries are getting expensive and disposing of them is becoming a problem. They're full of lead, and lead is expensive and toxic. It's in everyone's interest to make batteries last as long as possible - apart, of course, from the people who sell them to you!

The best way of making a lead-acid battery last as long as you can, is to keep it fully charged. I don't subscribe to the view that it's good for a car battery to be completely discharged and then re-charges from flat. Car batteries are generally designed differently from leisure batteries they're not supposed to be completely flattened and then re-charged. You can sometimes get an apparent small improvement by flattening a battery and then re-charging it, but in the longer term you are abusing its plates quite badly and in all probability reducing its useful life considerably.

If you lay up your car for long periods, and promise yourself that you'll charge the battery each week, and then don't, how about treating yourself to a mains timer? I have one which will switch on for 15 minutes a day, and cost me less than #9. If you charge your battery for 15 minutes a day on a trickle charge, that should do the trick and keep it nicely charged.

Relying on the alternator/dynamo to keep your battery up to scratch isn't the best way to do it. In a quest to make sure that don't overcharge the battery, most of these err on the side of caution. You can charge your battery more fully statically using a battery charger. With a modern battery charger, over-charging the battery is extremely unlikely unless you are very careless.

It's a fallacy that most batteries fail in cold weather, that's only when the symptoms show. As a rule of thumb, the power output of a battery doubles with every 10 degrees centigrade rise in temperature. That means that the power output at 20 degrees centigrade in the summer is eight times that at - 10 degrees centigrade on a bitter winter's morning. If you have a nice classic which you don't use in winter, why not take its battery/batteries off, keep them nice and warm in the house, and charged regularly using a timer? When the neighbour's cars won't start in mid-winter, you can walk out with a warm battery, a set of jump leads, and fire-up their car with little problem. If you want to start your pride-and-joy every so often in mid-winter, you'll have batteries capable of doing that too.

To make your batteries last as long as possible, always keep them well topped-up, and this includes maintenance-free batteries, if you can gain access. Distilled water isn't strictly necessary. You can use water obtained from de-frosting fridges and freezers, water boiled in a kettle and then allowed to cool, or even rain water. Going to your local shop and buying distilled water or de-ionized water for a car battery simply isn't worth it. Never top them up with fresh acid, you should only put acid in a battery if there has been a spillage of electrolyte.

Generally, the old wives tales about keeping batteries up to scratch are just that. Don't treat each cell with an aspirin. Keep those for a headache. Don't dose your battery with Epsom Salts or Glauber Salts either, you probably won't do it any harm, but you certainly won't do it any good. Additives that work just aren't this simple.

Make sure that the top of your batteries are always clean and dry. If they're not you can get conduction across the top, especially if a trace of the electrolyte has escaped by splashing on to the top of the case. If you've got a hairline crack around where the lead terminal enters the case, I've always found that cleaning around the crack and then sealing it with Araldite works nicely.

Of course, older batteries will begin to show their age, even with the best will in the world they won't last forever. When the time comes that you have to replace batteries, think carefully about how much you are prepared to pay. Will the battery that costs three times as much last three times as long? I doubt it! I always go for the cheapest battery I can find, and I've never been disappointed yet. My wife has a Triumph Spitfire (sorry about that!), and it is just going through its sixth winter on a battery that cost £15.95 - it was treated with EDTA when new and has just been looked after properly since.

When you look after batteries properly, you have to have an eye towards safety. Remember that when they charge, the gases given off create an explosive mixture. Don't smoke near them! They are full of sulphuric acid, and this isn't nice when spilled. Keep them on the floor, the higher up you store then, the more likely they are to fall, break and spill. If you do have an acid spillage, wash it down with masses of cold water, and ensure that the spilled acid never comes into contact with your eyes.

Do you have problems around your batteries on the car? You may have corrosion of the terminals, the leads, or even on surrounding bodywork. These can be caused by minute acid splashes or the evolution of acidic gases from the battery. Put Vaseline on the battery terminals once the leads are fitted. If you are suffering from surface corrosion on bodywork near to the battery, try the following sequence: wash the affected area with dilute washing soda solution, let it dry, paint with Hammerite, and then after a month or two, restore to the original colour. I've never known it to fail yet (but you might know differently!).

Finally, if you have any battery problems, remember that I'm always happy to talk to you and offer some friendly advice. My number is 01462 814827.

Kevin Martin, Shefford, Bedfordshire

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