How Long Do Electric Vehicle Batteries Last?

All battery-electric vehicles (BEVs) use rechargeable batteries as their main store of energy. The most common type found in modern EVs are lithium-ion based, the same chemistry found in many electronic devices, such as smartphones or laptops.

EV batteries are recharged by plugging the car to the grid, either from a home or public charging station. The battery is also recharged when the vehicle is slowing down or when the driver presses the brake through the process of regenerative braking. Lithium-ion batteries have higher energy densities when compared to other types of rechargeable batteries; making them ideal to support propulsion applications.

BEVs run entirely on an electric motor powered by a large internal battery. These batteries are generally maintenance-free, with any maintenance needing to be performed by trained technicians due to their high voltage (400-600 VDC or more). The battery is monitored by a battery management system (BMS) that maintains the cells within the battery assembly, generating fault codes if something requires attention.

There are a handful of reasons for EV battery degradation, including:

• Repeated deep discharge – Repeatedly discharging the battery to near zero capacity can degrade battery performance over many years. Storing an EV or leaving it parked for weeks with the battery at low states of charge can exacerbate battery degradation
• Operating temperatures — Like us, batteries prefer ‘comfortable’ temperatures. Exposing the battery to prolonged high temperature (>90F) and subfreezing temperature (<10F) can accelerate degradation. Fortunately, battery systems have evolved such that the BMS will maintain the battery in an EV in optimal temperature range, thereby reducing the risk of temperature related degradation.
• Using the EV — As with any electronic device that is powered by a rechargeable battery, normal use will bring about a certain level of degradation. However, normal use of an EV will yield many years of useable life without causing degradation that renders the vehicle inoperable. Many EVs that are seven to 10 years old still have perfectly functional battery packs.

• Always topping the battery up to 100% — Charging to 100% can strain your battery, eventually leading to a reduction in total capacity. Ideally, your EV battery should not be charged to more than 80%, although charging to 100% before a long trip should not lead to accelerated degradation, if done infrequently. Fleet managers can charge EVs every night — just not to 100%. Follow instructions from the EV manufacturer closely; in some cases the battery management system will automatically handle this for you.
• Repeatedly draining the battery to 0% — Batteries experience the most strain when they are either 100% charged or completely drained. It’s best to avoid draining an EV battery below 20%.
• Time — Just like the lithium-ion batteries found in electronic devices, EV batteries will eventually degrade over time due to what experts refer to as inevitable “calendar aging.”

It depends on whether the user has taken proper care of the vehicle and battery, but in general, EV batteries are expected to last much longer and log many more miles than internal combustion engine (ICE) vehicles.

The federal government requires that electric vehicle batteries have an 8-year/100K warranty. Many vehicles make it past the 200,000 mile mark with no significant reduction in battery.

While some degradation is expected, there are several steps fleet managers can take to prolong the life of their EV batteries:

• Limit battery exposure to extreme temperatures. Weather is an important factor in maintaining electric vehicle battery efficiency. Try to minimize exposure to extremely cold temperatures whenever possible, as it could affect the battery’s operating range.
• Consult manufacturer guidelines on battery performance. Each EV manufacturer should provide you with detailed information on the battery system and estimated charging range.
• Precondition the battery before you drive. Preconditioning refers to warming up an EV battery to normal operating temperatures so that it can charge more quickly. It’s ideal to have the EV running for a short time before you start driving in the winter months (you can program this in your vehicle’s computer system to condition before your trip).
• Minimize use of Level 3 fast chargers as a primary way to charge your EV. Although Level 3 chargers are the fastest way to charge your EV, they are only meant to replenish your battery in emergency situations, like during a long road trip for example. Regular and repeated use of high speed Level 3 fast chargers can accelerate degradation, though newer battery chemistries and technologies are becoming increasingly resilient against this phenomenon.

We pride ourselves on being an end-to-end EV provider that can help you find the vehicles you need while also strategizing and planning for fleet electrification. And once you secure your vehicles, we have the EV services, solutions, and support to keep your fleet up and running.

Our EV consultants are ready to answer your questions. Contact us today for more information or to get started on your EV adoption journey.