A new study by an Austrian battery health testing company, which has done over 500,000 independent battery health tests globally, including Australia, reveals that EV batteries are holding up longer than some thought.
Aviloo, which runs battery testing kits globally to check the state of a used car’s traction battery, shows that cars covering 150,000 km had between 87-94% battery health remaining, which is higher than what many in mainstream media have reported.
This comes from a total database of over 1 million tests conducted worldwide by plugging in a test kit device into the car. 500,000 tests run between 2022 and 2026 across 20 popular EV models were included in the study.
Battery health also varies within the same model, with test data showing that the percentage of a battery’s original capacity remaining can differ by up to 13.5% between the best and worst examples.
In the real world, this could be the difference between a car that comfortably does a long day trip and one that needs an extra charging stop.
This could also affect the car’s resale value down the track if the new buyer gets a lower real-world range than expected.
According to the latest report, a used Model Ys shows a median State of Health of 94.5% at 50,000 km, falling to 90.3% at 150,000 km which is equivalent to a real-world range per charge of around 379 km, then dropping to roughly 362 km. These results were only median values.
Individual cars vary by up to 11% in state of health across that range, worth around 46 km of real-world range per charge, which shows that the model average doesn’t tell you how any one car has actually aged.
Another finding of the report is that the median battery health of an EV drops as kilometres on the odometer increase but not consistently across all models. While higher the km on the vehicle, the loss of health doesn’t always convert to a consistent reduction, model’s averages differ.
Some EVs come with an on-board battery health test mode, which may not be as accurate since the car relies on its own battery management system to determine the battery’s state of health, rather than independent physical measurements of each cell within the used EVs battery pack.
According to the Australian distributor of the Aviloo battery health testing kit, Test EV, there are also implications for EVs locally, given the warmer climate found in many parts of the country, compared to some parts of Europe.
Off the back of this report, Nathan Gore-Brown, Director of Test EV said:
“Aviloo’s data confirms what we see on the ground here in Australia and New Zealand every week: a battery’s real condition can only be known by testing it, not by reading a dashboard or going off the odometer,” said Nathan Gore-Brown, Director of Test EV.
“A gap of ten or fifteen per cent in state of health is a genuine difference in range and in what a car is actually worth. Until an independent test exists for it, buyers, dealers and lenders have no way to see that gap coming. That’s exactly the problem Test EV was built to solve.”
With EVs becoming more mainstream, battery health testing will give thousands of buyers more confidence in making the switch to a used EV sooner and ditch their ICE vehicle altogether.
