A guide to electric car battery life

Understanding how long electric car batteries last is one of the biggest worries first time EV buyers have. Along with range – and the fear of running out of power mid-journey, known as range anxiety – the way an electric car’s battery might degrade over time is a big concern for potential electric car buyers.

Like any battery, including the one in your mobile phone or laptop, the batteries in electric cars will lose some of their capacity over time. So, how long do electric car batteries last and how can we extend the battery life? This helpful guide will give you all the answers you need to know about the electric car battery life in your MG electric car.

What are electric car batteries made of?

Most are made from lithium ion, and work in the same way as batteries in household appliances, mobile phones and laptops. Lithium ion batteries are lightweight and rechargeable - making them perfect for a travelling vehicle. However, this means that their power capacity will decline over time, much like our handheld devices, resulting in approximately 80% of the original capacity after eight years of daily use.

The key to overcoming range anxiety is to treat an electric vehicle exactly as you would a petrol car, only this time the fuel comes from a socket rather than a pump. As such, regular charging is required to prevent any potential power outages.

Knowing your electric car's range

Knowing the range of an electric car (how long it can run before recharging) is essential to ensuring it is always charged and ready to go. 

As with anything that’s battery-powered, electric car ranges vary between models and manufacturers. For example, listed below are the different ranges of MG’s range of hybrid and electric vehicles:

- MG5 EV Long Range: 250 miles
- New MG ZS EV: Up to 273 miles
- MG HS Plug-in Hybrid: 32 miles (EV only mode)

Once you know the range of your electric car’s battery before it needs fully recharging, you will be able to plan journeys accordingly and eliminate any potential range anxiety.

How long do electric car batteries last?

Electric car battery life is one of the main factors that makes drivers reluctant to switch to an electric vehicle. The batteries undergo cycles of 'discharge' that occur when driving and 'charge' when the car is plugged in. Repeating this process over time affects the amount of charge the battery can hold. This decreases the range and time needed between each journey to charge. Most manufacturers have a five to eight-year warranty on their battery. However, the current prediction is that an electric car battery life will last from 10 – 20 years before they need to be replaced. Advancements in technology, however, mean that the latest electric car batteries have a longer lifespan than ever before, including the New MG ZS EV which comes with a 7-year warranty.

This might seem remarkable when the battery in your mobile phone begins to wear out after only a couple of years, but during that time it might be fully charged and discharged hundreds of times. Each of these so-called charge cycles counts against the life of the battery: after perhaps 500 full cycles, a lithium ion phone battery begins to lose a significant part of the capacity it had when new.
While a couple of years might be acceptable in a phone, it's not good enough for a car designed to last many thousands of miles, so electric car manufacturers go to great lengths to make the batteries last longer.

In an electric vehicle such as the New MG ZS EV, batteries are 'buffered', meaning that drivers can't use the full amount of power they store, reducing the number of cycles the battery goes through. Together with other techniques such as water-cooling systems, this means that electric car batteries should last for many years.

How to make your car battery last longer

There are several tips that you can use to try and increase your electric car battery life:

- Charge the electric car battery between 20%-80% - The lifespan of the battery pack often depends on how much it’s charged. You can extend the life of the batteries by only charging them between 20% and 80% and trying not to let them drop below 50% too often. Going beyond these limits can increase the rate that the battery deteriorates over time.
- Avoid overcharging - Overcharging can cause chemical changes inside the battery itself, which again could negatively affect how efficiently it can store energy. Ultimately, you are looking to reduce the number of charging cycles that your battery goes through in its lifetime.
- Reduce exposure to extreme temperatures - Extreme cold or heat can negatively affect your car’s battery and therefore the range you can travel

Why does an electric car battery lose charge?

Almost all the batteries in electric cars are of the lithium ion variety. These batteries undergo ‘cycles’ of discharge (when you’re driving your car) and charge (when you plug your car in), and over time those cycles can reduce how much charge the battery can hold – and therefore, how far your electric car can travel before needing to be recharged.

Replacing an electric car battery

On average, electric car batteries last around 10 years, with some lasting up to 20 years, so you shouldn’t be concerned about replacing the battery before you’ve even bought a new car.
Leaving your battery flat and your car out of use could result in the battery pack no longer accepting charge (this is called bricking), but a lot of EVs, including the New MG ZS EV, have systems that prevent the battery fully depleting.

You may find the battery loses its capacity over time. This is natural, and often due to extended use. In the event of a battery fault, consult your warranty first.

So, in answer to the question of how long do electric car batteries last, it is estimated that the batteries should last approximately 10 years.