Introduction to EV Batteries
An electric battery is a device that stores chemical energy that is converted into electricity. The modern electric battery was invented by Italian physicist Alessandro Volta in 1800. This remarkable invention has enabled us to power much of our modern world with advanced devices such as laptops, smart phones, satellites, and even electric cars.
Consumers often have concerns about battery life when considering purchasing an electric vehicle (EV). The thought of replacing a battery pack is particularly daunting considering the average cost is $5,000-$15,000, and that’s not including the cost of labor. However, the battery packs that power today’s EVs are built to last longer than the vehicle itself.
How Long Do Electric Car Batteries Last?
The lithium-ion battery in your electric car is designed for extended life. However, electric car batteries will slowly begin to lose the amount of energy they can store over time. This phenomenon is called “battery degradation” and can result in reduced energy capacity, range, power and overall efficiency.
Battery degradation is not easy to predict. Not all brands perform the same, and every vehicle is different in how it is driven, charged and maintained. On the bright side, it’s not uncommon for modern EV batteries to last more than 10 years and some will go well beyond that before needing to be replaced. The average EV owner will sell their car long before they need to replace the battery pack.
Environmental factors, such as continued exposure to extreme temperatures, will impact battery performance and may lead to degradation. In particular, batteries don’t perform very well when the temperature is below 20 degrees Fahrenheit. When it’s really cold and you’re using the car’s heater, your range can temporarily drop by as much as 40%.
To maintain a battery pack at peak performance, it is recommended to keep EVs charged to between 60% and 80%, minimize fast charging and avoid extreme temperatures over long periods of time.
Battery Warranty from Automakers
Most automakers have an 8 to 10-year or 100,000 miles warranty period on their batteries. This is because federal regulation in the U.S. mandates that electric car batteries be covered for a minimum of eight years.
However, the terms of the warranty can vary. Some automakers only cover an EV’s battery pack against a complete failure while automakers like Tesla, Nissan and Volkswagen will honor the battery warranty if the capacity percentage drops below a specified threshold, typically 60-70%, during the warranty period.
Before purchasing any vehicle, it’s best to check the fine print on its warranties. For example, the Nissan Leaf has a percentage guarantee of approximately 75%; however, they use their own measurement units represented in “bars.” A full Leaf battery has 12 bars, and the included battery warranty guarantees it for nine bars of charge.
Battery repairs can be expensive, so it is important to understand the exclusions or conditions that can impact the warranty of an EV battery. Some exclusions might include, but are not limited to:
- Use of non-standard charging
- Any damage caused by using or installing non-approved parts
- Using the battery as a stationary power source
- Any damage caused by opening the battery coolant reservoir
- Failing to install software or firmware updates
- Damages or failures caused by repairs performed by non-certified technicians
- Lifting the vehicle from underneath the battery instead of designated body lift points
- Failure to make repairs
- Using the vehicle for towing and exceeding load limits
- General abuse or neglect
What About Hybrid Batteries?
Hybrid car batteries are similar to EV batteries; they are simply smaller. Since the gasoline engine, electric motor and battery work together in hybrids, if one is not performing optimally, it will impact the other.
Hybrid batteries typically last a vehicle’s lifetime with modern vehicles routinely reaching 100,000 to 150,000 miles or much more. Accordingly, automakers usually offer a warranty for at least 80,000 miles. In most cases, you can expect to achieve over double that mileage without an issue. Some automakers such as Hyundai even offer lifetime warranties. As a result, if you’re the owner of a hybrid you’ll likely never have to worry about replacing the battery.
There is also a time component to battery life — it degrades even if you don’t drive the car long distances. Hybrid batteries are designed to perform for at least 10 years. To cover any unexpected failure, time-based warranties are now standard in the industry. There is a federal mandate for warranties to cover eight years of hybrid car battery life, so most automakers offer warranties of eight years or more.
If you're faced with replacing a battery on an out-of-warranty car, there's no need to panic. The cost of a new battery pack continues to decline. Some technicians can even install an approved used battery pack salvaged from a wrecked vehicle, which would greatly reduce the potential repair cost.
Afterlife of EV Batteries
As electric car adoption continues to gain momentum, used batteries pose a serious challenge to the environment. What do we do with all the discarded batteries? As of this writing, there are two solutions: they can be recycled or repurposed.
Recycling must be handled properly, because toxic chemicals inside old batteries can lead to contamination of water and soil. As part of the recycling process, they are smelted to recover the lithium, cobalt, and nickel. However, this can be costly, so the repurposing of used batteries may be more cost-effective. Many EV batteries still have up to 70% of their capacity left, meaning they can be used for many other energy storage needs.
Automakers are exploring ways to profit from used batteries. In Japan, Nissan has repurposed batteries to power streetlights. In Paris, Renault has batteries backing up elevators. In Michigan, GM is using repurposed batteries from Chevy Bolts to back up its data center. VW recently opened its electric car battery recycling plant in Germany that can recycle 3,600 battery systems per year. Repurposed EV batteries can also be useful for storing solar energy or running electric bikes and other tools. Finding new ways to turn these used batteries into productive solutions will benefit businesses, the environment, and consumers.