Car battery care tips

Posted on February 4th, 2015 by Rob Marshall

batteryWith batteries being sealed, they tend to be ignored, until they are subjected to an outpouring of disgust, when they fail to start an engine.

With cold weather reducing their capacities and making engines harder to start, the savvy car owner can save money and reduce the chance of battery let-down, by following these ten tips:



1. Keep at full charge

Keep your battery fully-charged, as much as possible. The capacity of lead-acid batteries deteriorates, if kept below 100%. This can be difficult to maintain in winter, therefore, consider using a mains-powered smart charger, especially if you use your car for short journeys only.

2. Avoid long waits

Car batteries hate being discharged slowly, over long periods, and modern cars tend to consume power, even when parked and locked. Therefore, if you own a car that is decommissioned for longer than a month, disconnect the battery, take it indoors and treat it to a full charge.

3. Never ignore flats

Never allow a battery to become discharged, prior to being left for a long period of time. Chemical reactions will take place internally that will reduce its capacity and most of these changes are irreversible.

4. Check your belts

The battery is charged by the vehicle’s alternator, which is powered by a belt. Ensuring that this belt is tight (not over-tightened) and not showing signs of cracking is a vital part of regular maintenance. An illuminated battery light, on your dashboard, indicates that the battery is not being charged; it is not an indication of battery condition.

5. Do not overcharge

If you choose to charge a battery externally, never leave it connected permanently to an old-style trickle charger, because they tend to feed power continually. The resultant overcharging might cause the internal battery level to fall and, because most batteries are sealed, it might not be possible to replenish it. A modern, smart-charger is preferable and we are conducting tests on the most popular units currently.

6. Keep clean and tight

Ensure that the battery terminals are free from fluffy, white corrosion and that they are tight. This will ensure that current can flow freely to-and-from the battery. Pouring very hot water over the corrosion removes it effectively but make certain that you do not soak any of the vehicle’s delicate electrics. Use petroleum jelly (e.g. Vaseline), to keep the terminals clean. Make sure that the battery cannot move in its tray. An insecure battery is an MoT failure point and might prove dangerous in a harsh braking (or emergency) situation.

7. Long better than short

Many modern cars, especially well-equipped diesel cars, tend not to replenish their batteries, when all electrical ancillaries are in use, especially on short journeys. Therefore, a longer run will help the vehicle to replenish as much depleted charge as possible, which will make the battery last longer. Alternatively, consider charging the battery externally with a smart charger.

8. Get it tested

Eventually, a battery will wear out. Should your battery be out of its warranty period, get it charged fully, prior to having its discharge capacity verified by a suitable garage. This will let you know whether, or not, you should have the battery replaced, before it leaves you stranded.

9. Do not postpone replacement

Modern cars are very sensitive to short periods of low voltage, which result, when an ailing battery is struggling to start a cold engine. Electric power steering tends to be a popular item that stops working. Should your car be exhibiting strange electrical gremlins, suspect the battery before more complicated and expensive items. Always replace an ailing battery in good time.

10.  Replace like with like

Although you can buy upgraded batteries, some later car models, with either regenerative braking, stop-start (or both), will require an Enhanced Flooded Batteries (EFB), or an Absorbent Glass Matt battery (AGM), both of which are costlier than the conventional types. Never be tempted to cut costs, by fitting an inferior battery, or else the fuel-saving devices might not work properly. Some cars also require a new battery to be coded to the vehicle, so that it charges properly. Failing to do so might ruin your new battery.