Range is already a concern for prospective EV owners, and battery degradation will be an equally important factor – particularly as the used electric car market expands. In the same way your mobile phone’s battery may not hold as much charge as it used to, the same thing can happen to EVs. And worryingly, that reduction in capacity means a reduction in overall range.

How long do electric car batteries last? – Car Magazine – March 2021

 There are examples of used electric cars on BuyaCar that have gone way beyond 100,000 miles, some even passing 150,000 miles. Many drivers would stay well clear of a petrol or diesel car with that kind of mileage, so its fair to say these batteries have a reasonable life expectancy.

BuyaCar – April 2021
How long do electric car batteries last. Electric car batter in chassis
Curtesy of https://www.transportenvironment.org/

Battery Degradation

Over time these battery packs become less efficient in the same way a mobile phone does. Batteries degrade over time as they’re charged and discharged and won’t hold the same capacity as when they’re new. 

The key to Electric car Battery lifespan (longevity) is usage and charging pattern. The mileage does not indicate the state of the battery, indeed a lower mileage vehicle with a poor charging regime can offer higher value. This is one of several situations where unlearning of ICE (Internal Combustion Engine) thinking is required.

Modern EVs should still have a good capacity even after years of use. There are plenty of older EVs still on the road that are in fine order after thousands of miles and years of battery degradation.

How long do electric car batteries last? – Car Magazine – March 2021

Batteries typically degrade at around one percent per year, although it can be less with careful charging. Without a BMS it would be nearer 2% per year.

How long will an EV battery last? – Use the free EV Battery Degradation Tool to compare the average battery degradation over time for different vehicle makes and model years.

Causes of Degradation

  • Rapid charging
  • Taking the charging level to extremes
  • Rapid acceleration

Electric car Battery Lifecycle

Battery warranties

Manufacturers generally provide an Eight year 100,000 Mile Warranty, less than this is unusual and some offer more.

Isobel Sheldon OBE, chief strategy officer of Britishvolt, says that modern EV battery packs are designed to last up to 12 years and 1500-2000 charge cycles, making them ideal for most commuters. And once these batteries do become degraded, they have a second life as storage for renewable energy. 

How long do electric car batteries last? – Car Magazine – March 2021

Battery Longevity

Nissan Leaf example

Car batteries can be expected to last longer than the rest of the car. For some years an 8 year / 100,000 thousand mile battery warranty has been standard from most manufacturers, previously it was 5 years / 60,000 miles.

Older Leafs are not known for having a good Battery Management System, however despite that this example shows minimal battery degradation.

7 years old, 95,000 miles still with 85% Battery State of health

Battery Management System

Battery Management Systems are designed to reduce the impact of charging on the battery.

To understand any particular battery you will need to obtain the State of Health (SOH) figure.

Limited battery lifespan is one of the most common myths about electric cars. Not only do automakers like Tesla and Volkswagen expect batteries to last the life of a vehicle, but some expect them to last longer, and have proposed so-called “second-life” uses of batteries as stationary power sources.

Tips and Tricks

The first tip is to try to keep the battery from discharging to low levels, specifically below 20% capacity. That goes hand in hand with Hyundai’s second tip, which is to charge frequently in order to prevent the battery from draining too much.

Hyundai recommends charging every two to three days. This also ensures the car is prepared ahead of time for long trips, the automaker noted.

While driving, it’s best to avoid heavy acceleration, which drains the battery more quickly, according to Hyundai. Maintaining a consistent speed, rather than abruptly accelerating or braking, is the most efficient way to drive.

Nissan Leaf batteries are passively air-cooled, and hence lose capacity more quickly than batteries from Tesla, GM, and others that are actively liquid-cooled.

But long before recycling, electric-car batteries will have second and third lives well beyond their automotive use. Small businesses are forming to rack them for energy storage in buildings, etc. Some carmakers are even going into that business themselves.

The value of a battery that cost $5,000 to $10,000 new does not suddenly fall to zero, so people won’t want to just dispose of them them. They’re too valuable, and could live on for as long as a few decades.

Remember that manufacturers only design cars for lives of 10 to 12 years and 100,000 to 150,000 miles to start with, though Toyotas and a few other brands often last far longer.

Thus far, data shows Tesla batteries have only lost about 10 percent of their energy capacity after 100,000 miles.