The fear that an electric car's battery will wear out and cost a fortune to replace is one of the biggest things holding people back, and the real-world data has quietly put it to rest. Batteries degrade slowly and gradually, not in a sudden cliff, and most are comfortably outlasting their warranties. This guide sets out what the figures actually show and how to make a pack last as long as possible.
The short answer. Longer than most people fear. Real-world data shows electric car batteries degrade about 1.8 to 2.3 per cent a year, retaining roughly 80 to 90 per cent of their original capacity after eight years and 100,000 miles. Most makers warranty the battery for eight years or 100,000 miles to at least about 70 per cent capacity, and modern packs routinely beat that. A few simple habits slow the wear further.
The fear versus the data
The worry imagines a battery that works fine and then suddenly dies, leaving you with a five-figure bill. That is not how it behaves. A battery loses capacity slowly and steadily, so what you actually see over the years is a gradual, modest reduction in range, not a failure. A car that did 250 miles when new might do around 220 after eight years and a lot of miles, still perfectly usable. Large studies of real fleets, covering tens of thousands of cars, have made this clear, and the picture has only improved as the technology has matured.
How much they actually degrade
The headline figure from recent large-scale data is an average loss of around 2.3 per cent of capacity a year, with the best modern cars doing nearer 1 per cent. That compounds gently rather than dramatically, so the retained capacity after several years stays high.
| Age and use | Typical capacity retained |
|---|---|
| After 4 years | ~90 to 93% |
| After 8 years / 100,000 miles | ~80 to 90% (average ~82%) |
| LFP battery, 8 years | ~90 to 93% |
| Warranty floor most makers guarantee | ~70% |
From large real-world fleet analyses, mid 2026. Newer lithium iron phosphate (LFP) packs, increasingly common in standard-range cars, hold up especially well. Older air-cooled designs in hot climates degrade fastest.
The warranty backstop
You are not left to chance on this. Manufacturers warranty the battery separately from the rest of the car, almost always for eight years or 100,000 miles, whichever comes first, and that warranty guarantees the capacity will not fall below a set threshold, typically around 70 per cent. If it does, they repair or replace it. Since the average pack is still around 80 per cent or better at that point, most batteries never come close to triggering a claim, but the cover is there as a floor under the worst cases. It is worth checking the exact terms for a car you are considering, since the threshold and conditions vary a little between makers.
What ages a battery fastest
A handful of things wear a battery harder than ordinary use. Heat is the big one: sustained high temperature ages the cells, which is why hot climates are tougher on batteries than temperate ones, and why parking in the shade and not leaving the car baking at a full charge in a heatwave helps, as the EV range in hot weather guide covers. Frequent rapid charging is harder on a pack than slow charging, because of the heat and stress it puts the cells under. Routinely charging to a full 100 per cent and running down to empty stresses the battery more than keeping it in a middle band. And time itself plays a part, since cells age slowly whether the car is driven or not.
How to make it last
The habits that protect a battery are easy and mostly the same ones that save money. For everyday use, set the charge limit to around 80 per cent rather than 100, and only fill to full before a long trip, since sitting at a full charge is one of the harder things for the cells. Do the bulk of your charging slowly at home overnight rather than leaning on rapid chargers, which is gentler as well as far cheaper, as the best time to charge guide explains. Park in the shade or a garage in hot weather, and avoid leaving the car at a very high or very low charge for long periods. None of this is onerous, and a battery treated this way will hold its range well for many years.
What happens at the end of its life
Even when a battery eventually drops below the point where it suits a car, it is far from useless. Packs with plenty of capacity left are increasingly given a second life in home and grid energy storage, where the demands are gentler, and the materials in them are recyclable, with recovery improving as the industry scales. Replacement, the expensive worst case people fear, is rare within a car's normal life and getting cheaper as battery prices fall. For the running-cost picture overall, this durability is part of why an electric car's lower fuel and maintenance costs, set out in the EV versus petrol guide, are not undone by a looming battery bill the way the myth suggests.
The bottom line
Electric car batteries last well: they degrade gradually at around 2 per cent a year, keep roughly 80 to 90 per cent of their capacity after eight years and 100,000 miles, and are warrantied to about 70 per cent over that period, a floor most never approach. Heat, frequent rapid charging and sitting at a full charge are what wear them fastest, so charge to 80 per cent for daily use, charge slowly at home, and keep the car out of extreme heat. Treated sensibly, the battery will outlast the worries, and very likely the rest of the car's first life too.