The electric car has now reached the used market. Especially now that they are helped by a purchase subsidy, buyers are quite enthusiastic about this. An electric car has much fewer parts than a petrol or diesel car, so there is much less to break and that makes a significant difference in maintenance costs. On the other hand, the battery pack loses capacity over time. There is now a way to measure how much puncture is left in the battery and what is left of the range. Because if the battery pack fails, the replacement costs are so high that your occasion can be written off in one go.
The pressing question when purchasing an electric used car is what the battery pack is like. That is by far the most expensive part of the car. If it has to be replaced, the costs run into the tens of thousands of euros and an electric used car is in fact a total loss. The manufacturers of EVs obviously have equipment in house to measure the ‘degradation’ of their packages, but they are not generous with giving the results. For example, anyone who has a battery pack measured at Tesla will only be told whether it has surrendered more or less than 30 percent of capacity. In the first case, a new one is installed – provided the car still has the factory warranty. But they won’t tell you whether the battery has decreased by 5 or 20 percent. While if you ask us, measuring battery degradation should be the most important act before buying an electric car.
dongle
Marcel van Renselaar represents the Austrian company Aviloo in the Netherlands, which has developed a system to measure the battery of every electric car and determine the capacity. “After years of development, this test is new on the market and is now fully certified by TÜV.” Testing is a lengthy story, because obtaining the required data is different for each car model. But once it is possible to do such a test, you will have exactly what you need.
Marcel explains how the test works: “The battery must be fully charged. Then the Aviloo dongle goes into the OBD port and the car has to be run empty to less than 10 percent. Each individual cell in the battery pack is read and the voltage and temperature are checked at the same time. During the entire test period, the dongle automatically sends its measurement data to Aviloo. I can tell you the ‘state of health’ of the battery within two working days. A new WLTP range is then calculated based on that data.” If you do that test with a used car that you have in mind, then all ambiguity about capacity and range will in principle be eliminated.
According to Marcel van Renselaar, the results so far have shown that there are no brands or models with a bad battery pack. “The relegation mainly depends on how it has been dealt with. A battery that is always fully charged and empty degrades faster than a battery that is always between 30 and 70 percent charged. Chemically, a 50 percent charge is best. Furthermore, a battery does not like cold or extreme heat. A car that is always warm inside usually has a better battery than an EV that is outside in all kinds of weather.” Still, he says, there is still a lot of unexplored territory, because the EV has only just passed the pioneering stage. “For example, I’m curious about the lifespan of a battery in the end. Chemically, that should be ten years, and if you look at laptops, hearing aids or penlite batteries, that’s right. I wonder if that also applies to the electric car.”
Learning from testing
Aviloo started testing cars in the Netherlands last summer and there is now interest from all sides in the results. “The developers in Austria also learn a lot from the tests in the Netherlands. There are many more electric cars here. It would be nice if in the future a used car was offered with such a test result behind the front. Then as a potential buyer you have all the information about the most important part of the EV.
AutoWeek recently kicked off the new ‘Battery degradation’ section with a Nissan Leaf. We check the condition of the battery pack.
Looking for a used electric car? View the offer here.
– Thanks for information from Autoweek.nl