Electric car battery out of warranty: what now?

1. First, check that the warranty has really expired

The battery warranty is separate from the vehicle warranty, and considerably longer. With most manufacturers, it runs for 8 years or 100,000 miles from first registration, whichever comes first. It covers failure, but also loss of capacity below a threshold, generally around 70% of the original capacity.

• It belongs to the vehicle: a used buyer benefits from it until it expires.
• Some brands extend it if the car is serviced within their network, or apply different durations and mileages depending on the model and year.
• To find out the exact date, ask the manufacturer, quoting the vehicle identification number (VIN) shown on the V5C logbook.

If the battery is still under warranty, go to the manufacturer’s dealer network: the repair will cost you nothing. An independent garage only makes sense once that warranty has expired.

2. Why your car insurance won’t pay

Car insurance pays out on a claim: a collision, a fire, a theft, storm damage. Policies for electric cars often add the charging cable, the home charger or breakdown assistance if the battery runs flat.

A battery that fails on its own, or loses capacity over the years, is not an insured event under these policies. No standard policy covers it, not even fully comprehensive cover.

3. Extended warranties: what exists, and what to check

The only product designed for this risk is the used car or mechanical breakdown warranty, offered by specialist companies and mostly sold through dealerships and used car dealers. For the traction battery, the choice remains limited:

• The battery is frequently excluded, or only covered as an option.
• Contracts that cover it beyond the manufacturer warranty are often taken out before it ends, sometimes with a compulsory state-of-health check in the preceding months. Once the warranty has expired, it is often too late.
• Many apply a claim limit of a few thousand pounds, far below the price of a new pack, as well as age and mileage limits.
• Warranties offered on a private sale often exclude the traction battery, or cap it low.

Before signing, ask these questions and insist on written answers:

• Is the traction battery covered, and under which level of cover?
• Does the contract cover only failure, or loss of capacity too? From what threshold?
• What is the limit per claim, and is there an excess?
• What are the maximum age and mileage, when taking out the contract and during it?
• Can a repair with a reconditioned battery be imposed?
• Can the warranty be transferred if the car is sold?

4. Without a warranty: repair rather than replace

A “failed” battery is not always a battery that needs replacing. The fault often lies in a single module, a contactor or the battery management system (BMS). The manufacturer’s dealer network generally replaces the whole pack; specialist garages can work on just the part at fault.

The first step is a diagnosis: it establishes the battery’s state of health and locates the fault before any quote.

5. Buying used? The right reflexes

• Ask for the battery’s state of health (SoH, as a percentage).
• Failing that, have an independent diagnosis carried out before buying.
• Check the remaining battery warranty and, if it ends soon, the extensions available before it expires.
• Low capacity or an expired warranty are bargaining points: factor the cost of a possible repair into the price.