How long do EV batteries last, and how sustainable are they really?

At a glance

• Real-world studies indicate that most modern EV batteries degrade slowly and remain useful beyond their warranty periods.
• Battery design, climate, and charging habits can all influence how quickly capacity is lost.
• EV batteries have environmental and social impacts, but life cycle studies show electric cars produce fewer emissions overall than comparable petrol cars.

Questions about sustainability and lifespan of an EV battery are understandable. The battery is the most valuable component in an electric vehicle, and replacing a complete battery pack is expensive. But thinking of it as something that works perfectly one day and dies the next is misleading.

Like the battery in a phone or laptop, an EV battery gradually loses some of its ability to store energy. For a driver, that usually means a slow reduction in range rather than sudden failure. Because of highly sophisticated thermal management software in modern EVs, the battery generally remains usable for longer than many people expect. How quickly degradation happens depends on the battery itself, the climate, and how the vehicle is charged and used.

The growing number of older and higher-mileage EVs now provides a much clearer picture of what owners can realistically expect.

Are EV batteries bad for the environment?

EV batteries have an environmental footprint, and because of this electric cars currently produce more emissions during manufacturing than comparable petrol cars. However, the balance shifts when emissions are measured across the vehicle’s entire life.

A 2025 lifecycle analysis by the International Council on Clean Transportation estimated that a medium-sized electric car sold in Europe would produce 63g CO₂-e/km over its lifetime, 73 per cent less than a comparable petrol car’s 235g CO₂-e/km. With renewable electricity, this fell to 52g CO₂-e/km.

The ICCT found that an electric car’s additional manufacturing emissions, largely from its battery, were offset after about 17,000km of European driving.

In Australia, the Electric Vehicle Council’s lifecycle emissions calculator compares electric, petrol and hybrid vehicles using regional grid emissions. Its modelling finds EVs produce fewer lifecycle emissions across every vehicle segment, even under conservative assumptions. Readers can select their location and vehicle type to see when an EV’s higher manufacturing footprint is overtaken by the ongoing emissions from burning petrol.

Charging from solar or renewable electricity increases this advantage. Battery size also matters, as larger batteries require more materials and energy to produce. Choosing the smallest vehicle and battery that suit your needs can further reduce lifecycle emissions.

How long will an EV battery last?

There is no single age or distance that applies to every EV battery. A battery’s useful life depends partly on how much capacity it retains and partly on how much driving range its owner needs.

Geotab's analysis of 22,700 electric vehicles found average degradation of 2.3 per cent a year across 21 models. At that rate, a battery would retain about 81.6 per cent of its capacity after eight years, although degradation is not perfectly linear and often settles after a larger initial decline in the first few years.

A major new data set offers a closer look at how individual models are faring. The Aviloo Certified EV Battery Report draws on more than 500,000 independent battery test results collected between 2022 and 2026 across Europe, Australia, Asia and the Americas.

Aviloo bills it as the world's largest independent study of used EV battery health. Across the 20 models studied, most retained a median of around 87 to 94 per cent of their original usable capacity at 150,000km.

Among models sold in Australia, the Hyundai Ioniq 5 was a standout. Its median state of health was 97.2 per cent at 50,000km, 95 per cent at 100,000km and 92.8 per cent at 150,000km.

The Volkswagen ID.4 retained a median 90.6 per cent at 150,000km, while the Tesla Model Y recorded 90.3 per cent and the Model 3 about 88.9 per cent.

At the other end of the results was the 40kWh Nissan Leaf ZE1, which retained a median 86.3 per cent at 150,000km. Its smaller battery must complete more charging cycles to travel a given distance than a larger battery, while the Leaf also lacks the active liquid cooling used by many newer EVs. That can be particularly relevant in Australia's hotter regions.

Even so, a Leaf battery at 86.3 per cent state of health is not dead. It simply holds less energy than it did when new, reducing the distance available from a full charge. For someone using it for local trips, that remaining range may still be perfectly serviceable.

Aviloo also found differences of up to 13.5 percentage points between examples of the same model, with the spread tending to widen at higher mileages. This underlines why a model average cannot reveal the condition of an individual car.

There are some limitations to keep in mind. The study analyses test results rather than following 500,000 individual vehicles from new, and some model data combines different battery sizes. Although Australian vehicles contributed to the global data set, Aviloo has not published separate Australian results. Its figures are therefore a broad guide rather than a prediction for any particular car.

Taken together, the data suggests many modern EV batteries should remain useful well beyond their warranty periods. 

What affects EV battery degradation in Australia?

Battery chemistry, pack design and thermal management all play a part, but how and where an EV is used also matters.

Geotab found that frequent use of DC charging above 100kW was associated with faster degradation than lower-powered charging. Vehicles operating in hot climates also degraded about 0.4 percentage points faster each year than those in mild climates, a relevant consideration across much of Australia.

That does not mean Australians should avoid road trips or DC fast chargers. They are part of what makes an EV practical. But drivers who can do most of their charging at home or work may place less stress on the battery than those relying heavily on high-powered public chargers.

Leaving an EV battery sitting for long periods at a very high or very low state of charge can also accelerate ageing. Owners should follow their carmaker's charging advice, which may differ between lithium-iron-phosphate and nickel-based batteries.

Does an eight-year warranty mean an eight-year battery?

No. Eight years is a common battery warranty period, not an expiry date.

Many new EVs sold in Australia carry a high-voltage battery warranty of about eight years or 160,000km. Some warranties guarantee the battery will retain a minimum proportion of its original capacity, commonly around 70 per cent, while others place different conditions on capacity loss, faults and coverage.

A battery that reaches 70 per cent state of health can still work. It will hold less energy, provide less range than when new, and may charge more slowly, but it does not automatically need to be replaced.

Australian buyers should read the warranty terms for the particular model rather than assuming all brands provide the same protection. Manufacturer warranties also sit alongside rights under Australian Consumer Law, which may continue to apply when a vehicle fails to meet the consumer guarantees.

How can you check a used EV battery?

Odometer readings are useful, but Aviloo's results demonstrate that they cannot reveal battery condition by themselves. Two cars of the same model and mileage can have quite different remaining capacity.

When considering a used EV, check:

• its independently measured battery state of health
• the original usable battery capacity and what remains in kWh
• the battery warranty terms and whether coverage transfers to a new owner
• whether battery recalls and software updates have been completed
• whether the remaining real-world range suits your regular driving.

An independent EV battery report is particularly valuable when the car is approaching the end of its warranty, has travelled a high number of kilometres, or has an unknown charging history.