Car 101: Things that are ruining your car’s battery life

That tick-tick-tick of a dead battery is the last thing anyone wants to hear when they’re late.

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That tick-tick-tick of a dead battery is the last thing anyone wants to hear when they’re late.

A flat car battery is a quick way to ruin your day, and winter introduces more ways for your battery to drain.

Here are a few things to keep in mind when it comes to your vehicle’s battery health.

Cold weather

DAVID LINKLATER

There’s plenty you can do yourself to make sure your car is healthy for cold-weather driving.

A battery can lose as much as 35% in performance when temperatures hit freezing, and up to 50% 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.

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Considering the weather is out of our control, there’s not much that can be done – but something like a battery trickle charger can help mitigate any problems. And don’t forget to check other things that could be wrong with your car too, the cold doesn’t stop at the battery.

Too many short drives

Short trips drain your battery, as well as your fuel tank.

MONIQUE FORD/Stuff

Short trips drain your battery, as well as your fuel tank.

Nipping out on lots of short journeys, particularly in urban areas, also drains the battery, as it takes 150-350A of battery power just to start the car, and 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.

If you do need to duck out, and it’s not pouring outside, consider walking or cycling. Or, you could try and bundle a few other stops in to ensure your battery gets a decent recharge in. Plus, it helps save fuel!

Parasitic drain

Make sure your doors are properly shut to avoid any lights staying on overnight.

Markus Spiske/Unsplash

Make sure your doors are properly shut to avoid any lights staying on overnight.

This one might be obvious. Parasitic battery drain is something that constantly drains 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.

Leaving your key too close to your 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 in both the car and the key fob.

Self discharge

Car batteries will drain if they’re left alone and it doesn’t take long before they can’t start a car.

Christel Yardley/Stuff

Car batteries will drain if they’re left alone and it doesn’t take long before they can’t start a car.

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. Another good reason to pick up a trickle charger!

Sulphation

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 battery capacity and cranking potential. Your vehicle will easily start if the battery is at 12.4V but beware, your battery is already dying.