What is the average battery life of an electric car?

At a glance:

• EV battery lifespan is a common concern among new electric car buyers
• But, average electric car battery life is actually comparable to most petrol and diesel cars – expect at least 100,000 miles before it starts to noticeably decline
• All EV manufacturers offer decent warranties on their batteries (7 years+)
• Discover some of the key factors that affect EV battery life

Contents:

• Why do electric car batteries degrade?
• What affects the lifetime of an electric car battery?
• Do electric car batteries come with a warranty?
• How long is the warranty on electric car batteries?
• Can electric car batteries be recycled? 

Buying an electric vehicle is a major purchase, so naturally you’ll want to be confident that your new wheels will last you for the long run. This is why the battery life of electric cars is an important question for many new buyers. We’re all familiar with how smartphone batteries seem to run out of juice much faster after a couple of years use, so you don’t want to experience the same thing with your car. 

As a general rule, an EV battery is said to be degraded once it can no longer reach 80% of its original charge – at this point it won’t give you the range or reliability you need. 

The good news is that electric car battery life expectancy is actually pretty long. Most manufacturers today say you can expect the batteries to last at least eight years or 100,000 miles before reaching that 80% threshold. That’s about the same distance as in a traditional car before things start going wrong. According to a study by GeoTab, a firm that tracks thousands of EV’s performance, the battery life of an electric car will decrease by a fairly negligible 2.3% per year. 

So, how long do EV batteries last, what makes them degrade, and what protections are in place? Read our guide on electric car battery life expectancy to find out.

Why do electric car batteries degrade?

To understand EV battery life, it’s worth having a quick refresh on how lithium-ion batteries work – these are the rechargeable batteries used in EVs. 

As you might remember from chemistry lessons at school (put on your lab coat, don’t touch the bunsen burners!), all batteries contain an anode and a cathode at each end, with an electrolyte fluid between them. When a battery is charging up, ions (atoms with an electric charge) move from the cathode to the anode. When the battery is in use, the lithium-ions move the other way, discharging electricity which then powers the EV’s motor. Va-va-voom. 

EV batteries degrade for a number of reasons:

• Some of the lithium-ions are ‘lost’ through chemical reactions in the battery’s electrolyte, which means the battery simply has fewer lithium-ions available over time
• The battery’s electrodes (anode and cathode) will gradually get damaged as lithium-ions move in and out of them, reducing their capacity to store electric charge
• High temperature can cause the electrolyte to break down, which means fewer lithium-ions can pass easily back and forth through it

As you can see, EV battery lifespan is ultimately dictated by chemistry, yet there are a lot of other factors involved too. 

What affects the lifetime of an electric car battery?

While the degradation of the battery is inevitable, there are several other factors that impact  how long an EV battery lasts. These include:

• The car’s cooling system: All EV manufacturers use clever cooling systems to keep the battery at a stable temperature. Generally speaking, those with liquid cooling systems last longer than those with air cooling systems (though the difference is small). 
• Temperature: Since high temperatures damage the battery’s electrolyte, EVs in warmer climates tend to have a shorter lifespan than those in more temperate places. 
• Using fast charging too often: Fast charging is a great way of topping up your EV battery quickly, but it does increase the temperature inside the battery more than regular charging – and that can degrade the battery. Occasional fast charging is fine, but do it often and it will affect the battery life of the electric car. 
• Overcharging and running low: Your battery will last longest when charge is kept somewhere between 20% and 80%. While it’s tempting to ‘fill’ the battery up to 100%, this is only really necessary before long trips – charging till full and then draining till empty affect how the battery stores energy. Most manufacturers recommend charging only to 80%. Read our electric car charging guide for more tips and advice. 
• How you drive: If you drive quickly and aggressively, this will cause the cells to deplete faster and that, in turn, affects their longevity too. 

Do electric car batteries come with a warranty?

Yes. EV manufacturers know that electric car battery life expectancy is a big concern for most of us, so they all offer warranties should something go wrong. Check the website or sales brochure of any car you’re interested in buying to find the exact figures. 

How long is the warranty on electric car batteries?

Almost all manufacturers today provide a warranty of eight years or 100,000 miles on EV batteries (remember that these are warranties solely for the battery – the rest of the car will have a different warranty). 

Some even offer more – the Tesla Model S has an eight year warranty or 125,000 miles, as do some of the latest Hyundai EVs. There are also a couple of EVs with a seven year warranty, and a handful that only promise support up to around 65,000 miles. Make sure you read the brochures for any EV you’re thinking of buying so you know how much you’re covered. 

It’s worth remembering that these battery warranties are considerably longer than the warranty you’d get on most traditional petrol/diesel powered cars. Since EV motors have far fewer moving parts than internal combustion engines, they tend to last a lot longer. And as EV batteries improve, we can expect battery life to last longer too – some manufacturers have been promising the arrival of ‘million mile batteries’ in the near future. 

Can electric car batteries be recycled?

Yes, EV batteries certainly can be recycled. There are broadly two ways they can be repurposed:

1. Recycling for raw materials: EV batteries contain a variety of valuable metals, including lithium, cobalt, nickel and manganese. The battery can be shredded, ground to a powder and undergo various chemical treatments to extract these metals. They can then be reused to produce new EV batteries, or for other uses. 
2. Repurposing the batteries: After the end of the initial EV battery lifespan, the cells can be repurposed for many different applications. They can be used for home or workplace electricity storage – such as for storing energy from solar panels to use at night. Some companies are building mega batteries out of used EV cells to use in power grids. And they can also be installed in other vehicles that need less power, such as forklift trucks or golf buggies. 

Read our article about electric car battery recycling to learn more about extending EV battery life after they’re no longer suitable for use in vehicles.

It’s very common to have concerns about the battery life of a new EV. But, generally speaking, you can be pretty confident that the battery will last as long as you need it – and maybe even longer than comparable petrol/diesel powered vehicles.