A flat car battery is annoying, especially when you’re pressed for time, and it’s becoming more common with today’s power hungry technology in increasingly smart vehicles.

But there are some things you can do to minimise the risk of being stranded when you least need it.

We got some tips from UK-based battery-charger manufacturer CTEK, which says there are 10 things flattening your battery’s life — and some are, unfortunately, inevitable for most motorists.

1. You’re taking too many short drives

Nipping out on lots of short journeys, particularly in urban areas, drains the battery, as it takes 150-350A of battery power just to start the car. On short trips, the alternator won’t have the time or capability to replace this charge. Over several short trips, your battery will soon be flat.

A battery can lose as much as 35 per cent in performance when temperatures hit freezing, and up to 50 per cent if temperatures sink below that. Drivers should look out for any signs of change — like the way the car starts, or the operation of the electrical system in general — as these can be indications of a weak battery.

3. Leaving your keys close to the car

Leaving your car key in your car overnight, or even on a hook near the car, is not recommended. If the fob is too close to your car, it can continue to communicate with it, which could needlessly drain the battery.

Your standard lead-acid battery will naturally drain at 0.1V per month, even sitting on a shelf. That may not sound a lot, but if we consider that a fully charged battery is at 12.72V — and a chemically discharged battery, at which point you’d struggle to start the car, is at 11.8V in just eight months of non-use — the battery could appear flat. That is without considering any additional drains that may also impact battery life, too.

5. Continual power draw when parked

Even while your car is off, your battery provides power to things like the clock, the radio, and the alarm system, though these things shouldn’t have a major impact on its life. With modern vehicles, though, you’ll also find that engine cooling fans and other systems will keep running after the ignition is turned off to, for example, quickly cool down the engine and prevent damage. The vehicle may run its own network with communication to the manufacturer servers via the TCU (telematics control unit) for over-the-air updates that are sent out on a regular basis. Additionally, the ability to remotely turn on the lights, heating and cooling from your phone via an app can also go through this network.

6. Opening the doors and boot

Every time you open the doors or boot to get something out, your car springs into life and the interior and door lights will drain the battery. As an example, unlocking your vehicle, popping the boot or tailgate and locking it again can draw around 50A from the battery. It doesn’t seem a lot, but regularly doing this can have an impact on battery voltage, especially as all the vehicle’s systems become active for the short time that the car is opened up.

Parasitic battery drain is something that constantly affects your battery. This could be a headlight/dome-light switch, alternator, or any other electrical gremlins. You can help avoid parasitic drains by turning off every light and making sure your boot, glove box and doors are fully closed and locked before leaving the car.

Your car relies on your battery when you fire up the engine. But when your vehicle is running, your battery relies on the alternator to help it stay charged. If your alternator isn’t working correctly, it won’t charge your battery properly, which can make it hard to start your car, even if you were just driving.

If your battery falls below 12.4V, a chemical reaction called sulphation will start to happen. This is where lead sulphate crystals start to build up on the battery plates, degrading the battery, reducing its capacity and cranking potential. Your vehicle will easily start if the battery is at 12.4V but, beware, your battery is already dying.

Nothing lasts forever, including your car’s battery. In many cases it depends on where you live, how you drive and how you look after it — though, did you know, that more than 87 per cent of batteries returned under warranty are not faulty; they are suffering from sulphation. Extreme temperatures, frequent short trips and general everyday use could shorten the life of your battery to as little as two to three years if you don’t look after it.

CTEK recommends charging your car battery using a reliable battery charger at least once a month to prolong its life by up to three times.

There are many battery chargers to choose from, ranging in price from under $100 to more than $500.

Repco has CTEK’s MXS 5.0 in a couple of variants for $159-$336, but you can get a basic battery charger for $89 and there are various brands to choose from, including Projecta (starting from $150), Milwaukee (from $174) and Maxi Trac (from $199 with solar input).

Supercheap Auto has SCA battery chargers starting from $60, Century (from $135), Projecta )from $160), Ridge Ryder (from $250) and Calibre (from $300), plus more.

WA-based iTechworld has the iTECHBC20 battery charger currently on sale for $299, plus jump-starter back-up power banks, such as the JS80 ($450 but currently on sale for $349), which also has USB ports and can run 12V appliances.

The store is at 281 Great Eastern Highway, Burswood, or online at itechworld.com.au.

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