EV batteries: everything you need to know

What makes an EV different to an ICE vehicle? It’s an obvious answer – electricity. EVs are powered by a battery, rather than a traditional engine. The concept of a vehicle powered by electricity isn’t new, but it’s not uncommon for drivers to lack understanding of the battery technology. In this blog post, we’re answering some common FAQs regarding EV batteries.

How long do EV batteries last?

EV batteries are an expensive element of the vehicle’s makeup, which can deter people from making the switch from an ICE vehicle. As of March 2023, the average (estimated) cost for an EV battery was £5,378.43, but this varies by the make and model of the vehicle. This doesn’t include the labour costs of removing the old battery and fitting the new one, so the price could be even higher.

Don’t let this price deter you, as it’s unlikely you’d ever need to replace the battery in your vehicle. When buying an EV, most manufacturers offer a 5 to 8-year warranty on the battery. However, it’s predicted that most EV batteries can last 10-20 years before needing replacing. Battery technology is constantly evolving, so it’s likely that this predicted lifespan will only increase as the years go by.

It’s important to remember that EVs have fewer moving parts than an ICE vehicle, and therefore often have lower maintenance costs as there’s less to go wrong. Even if you did find yourself needing to pay out for a battery replacement, the vehicle will likely have cost you less over time than a petrol or diesel alternative.

Do EV batteries degrade?

EV batteries do degrade over time, leading to their expected lifespan as mentioned above. The rate of degradation can depend on several factors, including the type of battery, driving conditions, and how well the battery is managed.

There are certain measures EV owners can take to help slow the degradation of their batteries, but many factors are unavoidable and will come with the general use of the vehicle. Here are some reasons why an EV battery degrades over time:

• The vehicle’s design can impact degradation rates. How the battery is integrated into the vehicle and the on-board thermal management system can both impact the vehicle’s ability to dissipate heat and therefore influence the rate of battery deterioration.
• Lithium-ion batteries undergo chemical reactions whilst charging and discharging, which can lead to the breakdown of electrode materials and electrolytes. This will decrease the battery’s capacity over time.
• High temperatures accelerate the chemical reactions in the battery, speeding up degradation. Cold temperatures can also impact the battery’s capacity by interfering with the chemical processes. EV manufacturers often include thermal management systems to mitigate temperature-related stress, but this is still a common factor that contributes to battery degradation.
• When an EV is plugged in and the battery is recharging, the battery enters a charging cycle, and when the EV is driving and using this stored electricity, the battery enters a discharging cycle. As an EV goes through these two cycles, it gradually loses capacity. It’s recommended to charge an EV slower with a lower power chargepoint rather than frequent rapid charging to help ease the strain on the battery and slow its deterioration. Fast and rapid charging generates more heat compared to slower charging methods, putting more strain on the battery.

Are EV batteries dangerous?

We’ve all heard the stories of EVs catching fire, seemingly spontaneously, but how plausible are these fears? The electrolyte in lithium-ion batteries is indeed highly flammable and its power cells can short circuit if damaged, however, that shouldn’t be a concern for drivers. 

Manufacturers have to comply with strict safety regulations, including crash tests, immersion tests and combustion tests, before a battery can be installed onto a vehicle. The battery is also divided into smaller cells with separating fire-walls, rather than one big battery pack, which can prevent disastrous damage if one of the cells malfunctions. On top of this, the battery in an EV is surrounded by coolant liquid to maintain a safe temperature.

Every EV battery will have a management system which controls every aspect of the battery to ensure optimal performance. This includes monitoring and regulating the charge level of every individual cell, deciding which cells to charge or discharge and monitoring the battery’s temperature. The management system can automatically adjust energy use if any aspect of the battery’s operation gets outside of normal values, and if necessary, alert the driver of any battery-related risks or concerns.

Although the makeup of an EV battery can potentially pose a fire risk, lithium-ion batteries actually have a significantly lower risk of fire explosions than a gasoline engine, meaning that an EV is safer than an ICE alternative. EV manufacturers are also working to develop batteries that are even safer than those we have today.

How EV batteries are made

Similar to other types of batteries, EV batteries are composed of cells that contain a positively charged cathode, a negatively charged anode, and an electrolyte to separate them. EV batteries are often made up of either carbon or graphite, a metal oxide and lithium salt. These elements make up the positive and negative electrodes, which are then combined with electrolytes to produce an electric current. This chemical combination produces the electric current. These cells are grouped into modules which are all connected to form the full-size battery pack, enclosed in a casing made of aluminium or steel that holds the battery pack together and protects against mechanical damage.

China is the biggest producer of EV batteries, with large contributions also coming from Germany, the US, Japan and Korea.

Can EV batteries be recycled?

Most EVs use lithium-ion batteries, of which about 80% of the components can be recycled. Specialist firms can dismantle EV batteries into their parts which can then be individually recycled for various other uses. The process of recycling an EV battery can be both costly and time-consuming, but it is beneficial for reasons of both safety and sustainability. EV batteries contain toxins which can be harmful if handled incorrectly, so they cannot be safely chucked into landfills.

Metals such as nickel and cobalt can be retrieved from old EV batteries and repurposed elsewhere – these materials are expensive and often mined in lower-income countries under problematic conditions, so recycling any traces used in a now-redundant EV battery is well worth the money and time. Lower-value materials may not be retrieved from the battery, such as plastics, copper and aluminium.

Some batteries will not be recycled but will be reused instead. A battery that can no longer power a vehicle for long-distance driving could still have enough storage capacity for use elsewhere. In 2018, Nissan experimented with using both old and new EV batteries to power a Dutch sports stadium.

Understanding how an EV mechanically operates isn’t a necessity for every driver, but it can help you feel more confident with your vehicle. If you’re looking to install a chargepoint at home or your business, get in touch with our expert team today.

If you had difficulty understanding any of the terminology or acronyms in this post, check out our EV glossary.

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