Test the battery in a used e-car

Imagine that with a combustion engine: A tank that is getting smaller and smaller. From 60 to 50 or just 40 liters. And that’s not all: the internal resistance of the battery increases over time, and this results in a loss of performance when accelerating.
For buyers of a new e-car, the transience of the power storage is usually not an issue, as the manufacturers give generous guarantees on the batteries. Eight years or 100,000 miles in most cases, whichever comes first. For some, however, the assumption of costs ends at 100,000 kilometers.
Used e-car: The battery pack accounts for around 50 percent of the vehicle’s value
Buyers of used cars must therefore take a closer look, because the battery pack accounts for around 50 percent of the vehicle’s value. The older a car gets, the higher this proportion. If the battery fails in an e-car that is getting on in years, it is usually a total loss and repairs are no longer worthwhile. So be careful with short remaining warranty periods or a kilometer eater. Here it is imperative for the workshop to check the condition of the traction battery with the appropriate diagnostic software.

Diagnosis: The individual cells can be read and reveal their condition.
The automotive supplier Mahle, for example, supplies such a device. The “TechPro”, according to Mahle, is the first tool that enables basic diagnostics via the OBD port. When assessing the battery condition, professionals speak of SoH, which stands for State of Health. The corresponding control unit for battery management is usually read out for this purpose. If the determined capacity is below 70 or 75 percent, the car manufacturers speak of a guarantee case.
In addition, a battery analysis via the charging socket should soon be possible. Supplier Mahle and software specialist Volytica Diagnostics have developed a charging and diagnostic device that is currently being tested in practice by TÜV Nord. This should read the state of health of the battery in ten minutes, regardless of what data the manufacturer provides via the OBD port. This type of diagnosis would thus be particularly neutral. For example, any need for repairs can be predicted.
The driver can also control how quickly the battery wears out
This is how car manufacturers and testing organizations test batteries
Audi
DEKRA
ford
goodbye
Hyundai/Kia
Mazda
Mercedes
Renault
Seat
Skoda
MOT South
Volkswagen
Even with full batteries, you shouldn’t park a car, it’s better to drive off immediately. If you drive a lot of short distances, you should stay below 80 percent when charging, because the battery feels most comfortable between 20 and 80 percent. And: Avoid driving at full throttle and sprinting at traffic lights.