for immediate release
Electric Vehicle batteries lasting well so far
Nissan Leaf batteries will deliver at least 85 km range on average after 10 years, with some models going further. This estimate is from Flip the Fleet, a citizen science coalition of electric and plug-in hybrid vehicle owners that upload data from their vehicles to a communal database each month.
“Many people are understandably passionate about battery health in their electric vehicles”, says Dr Myall, Flip the Fleet’s statistician. “It determines the EV’s range and affects resale value. Just as your cellphone battery gradually loses its ability to hold charge, so too an EV cannot store as much energy as it gets older”.
“For most EV owners, we have good news”, says Dr Myall. “The battery in Nissan Leafs, one of the commonest EVs on our roads, loses on average between 2% and 4% of its range each year”.
“In an earlier questionnaire, most EV owners reported that, ideally, they will want to refurbish their battery or replace their EV once its range falls to around 85 km. The actual average daily travel by car in New Zealand is less than 29 km. We expect Nissan Leafs to achieve at least this distance for many years to come”, says Dr Myall.
The Flip the Fleet team are struck by the huge variation between cars in battery health – one has only slipped to 95% charge holding capacity over 5 years, while another is down to 71% after 6 years. The citizen science project wants to find out why some batteries last way longer than others so they can advise how owners can protect their investment. It is the age of the car that matters most – there is no evidence in the Flip the Fleet database so far that battery capacity is greatly affected by overall distance travelled or how many fast charges it has had.
“We need more data for EVs as they age in New Zealand conditions before we can find out what causes the variation in battery health, and to check that rates of decline observed so far continue throughout the life of the battery. We hope more EV owners will sign-up to help Flip the Fleet so that we can learn faster”, says Dr Myall.
Considering that the first Nissan Leafs hit the road in 2011, some will become impractical by 2021 – which is another 4 years away. The most pessimistic outcome would have the earliest EVs needing battery refurbishment in a few years. Batteries in the newer and more expensive electric vehicles are expected to have a longer life than these early Leaf models.
Fortunately, New Zealand already has a fledgling battery refurbishment industry, led by Carl Barlev from Bluecars in Auckland.
“We just need to scale up this support industry in the next few years to extend the life of these very early entry-level EVs”, says Mr Barlev.
“The battery can have an afterlife as a power storage pack in your house. But propelling your car for over ten years is a good first innings and well within the range where the savings on the fuel and maintenance more than pays for the replacement battery you will need eventually. At the moment, refurbishing your battery will cost between $2,000 and $5,000, not much for at least another decade of low cost motoring”, says Mr Barlev.
The newer model EVs have bigger and better batteries, so it’s even less of an issue for them. All up then, battery capacity decline is likely to be a small and manageable issue for most EV owners and battery replacement costs are sufficiently low to make electric vehicles an excellent life time value proposition.
The Flip the Fleet project is described at: www.flipthefleet.org. See the ‘Discussion’ and the ‘Resources’ pages there for further data and results of a recent survey of New Zealand’s electric vehicle owners about battery health.
For personal quotes from a recent survey on this subject, see http://flipthefleet.org/2017/1-click-survey-13/
Contacts for more statements:
Daniel Myall, New Zealand Brain Research Institute, Christchurch. 027 222 2585. firstname.lastname@example.org. He is a statistical modeller and owns a Nissan Leaf. Photographs of Dr Myall are available on http://flipthefleet.org/resources/founder-photos/
Carl Barlev, Blue Cars, Auckland – 021 499 122 – email@example.com
Henrik Moller, Prof Emeritus, Centre for Sustainability, University of Otago; and cofounder of Flip the Fleet – 027 2268 688 – firstname.lastname@example.org
Dima Ivanov, PowerStats Ltd.; and cofounder of Flip the Fleet; 021 927 346; email@example.com
Flip the Fleet has members spread throughout New Zealand. We list the contact details of some local contributors below in case you want to get a local perspective for your story. Please ring 027 2268688 or Email firstname.lastname@example.org so we can find a local member to speak to you.