Noticing that your car battery keeps dying is never pleasant. There’s nothing worse than turning the key and hearing that dreaded clicking sound, or worse, nothing at all.

However, there are a few common reasons behind this situation and, more importantly, a few ways to prevent your car battery from draining quickly. Here’s what you need to know.

Key takeaway

• Common reasons your car battery is draining quickly
• How to prevent your car battery from dying
• Why your electric car battery keeps dying
• Ways to keep your EV battery healthy
• Last thoughts

Common reasons your car battery is draining quickly

Noticing your car battery draining repeatedly? It might be because of these reasons. 

Too many short trips

Popping to the shops might be more harmful than you think. 

Starting the engine draws a significant amount of power, and if the alternator doesn’t have enough time to replace that energy, your battery may gradually weaken. 

This means that if you regularly drive short distances, your battery may not have the opportunity to fully recharge. 

Old or failing battery

Car batteries don’t last forever. On average, they need replacing every three to five years.

If your car is struggling to start or if the lights seem dimmer than usual, your battery might be on its last legs.

Something was left on

Forgetting to turn off your headlights and interior lights or even leaving a USB charger plugged in can drain your battery overnight. 

Some newer cars turn lights off automatically, but it's always worth double-checking when you leave your vehicle.

Faulty charging system (defective alternator)

Your car relies on the alternator to keep the battery charged while driving. 

If the alternator is faulty or the drive belt is slipping, your battery won’t receive the power it needs, eventually leading to a flat battery.

A local garage can help you resolve this problem, and car repair finance from Bumper can help you split the costs.

Extreme temperatures

Notice that your car battery keeps dying when the weather changes? Well, that’s because very hot or freezing weather can impact your battery’s performance.

In the cold, the battery has to work harder to start the engine. In contrast, excessive heat can cause the battery fluid to evaporate, leading to internal damage.

Parasitic drain

Even when your car is switched off, certain systems, such as alarms, clocks, and infotainment units, continue to draw a small amount of power. 

This is known as a parasitic drain, and although it’s typically minimal, faulty components or aftermarket parts can sometimes cause excessive draw, leading to a flat battery.

How to prevent your car battery from dying 

These days, you don’t have to put up with your car battery draining quickly. Use the tips below to prevent future frustration.

1. Change your lock-up habits

Good habits are gold dust!

When you park and lock up, make it a habit to switch off the headlights, interior lights, and unplug any accessories before leaving your vehicle. It only takes a few seconds, but it can save you from a flat battery.

2. Drive for longer

If you mainly take short trips or don’t drive daily, you may want to try going for a longer drive once a week. 

Of course, this won’t be possible for everyone. In this case, consider investing in a trickle charger or battery maintainer to keep your battery topped up when your car is parked for long periods.

3. Don’t ignore warning signs

Don’t ignore dashboard battery warnings. Take action if this appears. 

Likewise, keep an eye out for:

• Slow engine cranks
• Dim headlights
• Clicks when you turn the ignition key
• Poorly functioning car accessories

These could all be early indicators of a dying battery or charging problem, and you can prevent a dead battery by acting fast.

4. Park in a sheltered area

Extreme temperatures can cause dead batteries if your car is left exposed.

Parking your car in a garage helps protect it and extend battery life. If a garage isn’t available, try to park in a shaded or sheltered spot.

5. Get the battery checked

Sometimes, there are no signs before a car battery dies.

A quick battery health check can identify potential issues early. Many garages will test your battery and alternator for free or at a low cost. 

Pro Tip: It’s best to check before winter or long road trips.

Why your electric car battery keeps dying 

Just like petrol or diesel cars, electric vehicles are susceptible to battery drain when left unused for an extended period.

Some reasons for poor EV battery health include:

• Parasitic drain due to modern features like climate control, infotainment systems, and even software updates.
• Frequent use of rapid chargers which can heat the battery and degrade its long-term capacity.
• Leaving your EV parked for weeks with a low state of charge. This can cause the battery to fall into a deep discharge, which is harmful over time.

Ways to keep your EV battery healthy

Preventing fast EV battery drain is also preventable. 

If you’ve noticed your EV battery keeps losing charge, start with the following strategies:

• Avoid overcharging. Try to keep the charge level between 20% and 80% rather than charging to 100% each time. 
• Avoid dropping to 0%. On the other hand, you also want to charge the battery before it runs out of power.
• Use rapid charging only when necessary. Fast chargers generate more heat and can degrade the battery.
• Regular software updates can also optimise battery performance and efficiency.

Last thoughts

Whether you drive a petrol car or an EV, a car battery that keeps dying is never fun.

But with a bit of regular maintenance, attention to warning signs, and smart charging habits, you can prevent unexpected breakdowns and improve your car’s health.

Split the cost with Bumper

Empty batteries are just as frustrating as last-minute repair costs.

With Bumper's car repair finance, you can split the cost of repairs into monthly payments at no extra cost. 

Apply online for up to £5,000 and choose from 1,000s of trusted repairers.