Will my EV battery last?

For a world used to mobile phone batteries seemingly lasting barely one day past the warranty period before dying … and the replacement cost often being more than the cost of a new phone, it was hardly surprising that the same negative expectation would be brought to battery electric vehicles (BEVs).

Adding to this mix was the first big selling EV (the Nissan Leaf) having batteries prone to accelerated degradation when used in hot climates and/or when they did a lot of DC fast charging.

The result was that the idea of EV batteries not lasting became not only cemented into public thinking, it became generalised to all EVs.

(Nissan’s problems by the way sprang from a combination of an early battery chemistry prone to heat degradation and no battery cooling system. Nissan addressed the first issue with a change in battery chemistry – although to this day, the Nissan leaf still has no cooling system!)

Manufacturers since have worked hard to dispel this impression. EV batteries are now a well-developed, time tested technology and (in all but the Nissan leaf) also have active cooling systems.

Battery warranties have also been structured to further instil confidence with commonly 8 years coverage for a minimum of 70% to 80% capacity remaining.

This, it should be pointed out, is the worst-case scenario: studies show that degradation rates are commonly 0.5% to 1% a year. At that rate, a 500km range BEV when new will have between 450 to 475km range left after 10 years use.

As another example, Tesla in their 2022 impact report found that Models S and X batteries lose on average 12% of their capacity after travelling 200,000 miles (320,000km). Given the average Australian passenger vehicle travels roughly 12,000 km a year – that 320,000 km equates to over 26 years of driving.  

Even with all that battery improvement work, warranties and data – some people are still not satisfied that EV batteries will go the distance.

Enter the California Air Resources Board,(CARB). From 2026 onwards, BEVs sold in California must be warrantied to retain at least 70% of the original range for 10 years/240,000 km (up from 160,000 km and 8 years). This will increase further to 80% of the original range for 2030 and beyond model year cars.

Their reasoning for the changes?:  “(These) durability and warranty requirements in the regulation will help establish a viable and dependable used ZEV market”.

As with all California based vehicle rules, the changes will almost certainly flow through to the 40% of the US market that follow California’s settings. The EU is also looking into adopting them.

Plus, even if Australian consumer law does not change to reflect the new overseas rules – manufacturers here are likely to move their warranties up to these standards simply to gain a competitive advantage.

After all, if battery life is a commonly perceived worry – why not use it as a selling feature? Who amongst this group isn’t going to consider more favourably the EV with a longer time/distance, higher percentage warranty over a lower life/distance one?

And, as stated in CARB’s reasoning for the changes – it will instil greater confidence in the second-hand market as EVs move into the next phase of the transition and move into the hands of subsequent owners.

Overall, in order to instil confidence in the technology beyond the first adopters and into the general vehicle buying public – these are the sorts of legislative changes we need to see as the EV Transition progresses. Hopefully too, warranty requirements and related issues will be one of the topics that is addressed in the upcoming Federal government inquiry into the EV Transition.