Anyone who deals with electric cars will inevitably be faced with the following question at some point: What happens when the battery is dead? One widespread misbelief is that they end up going straight into the garbage. However, that would not only be uneconomic, but also a waste of valuable resources. So, how easy is it to maintain the high-voltage traction battery in an electric car and can it, in a worst-case scenario, be repaired after a crash?
Battery lifespan Battery repairs in an electric car – is that possible?
Is the electric car dead and buried if the battery is broken? No, as it can usually be repaired. We visit the Volkswagen Qualification Center in Erfurt, where high-voltage experts are trained.
Modular structure simplifies repairs
Yes, that is possible. Trainers like Johannes Walther at the Volkswagen Qualification Center in Erfurt explain exactly how to employees of Volkswagen service partners. If damaged, the modular structure of the high-voltage battery allows partial repairs, as well as an accurate diagnosis. As a rule, this is the more economical option, compared to replacing the whole battery.
Volkswagen has two Qualification Centers, in Erfurt and Wolfsburg, at which employees are trained to become high-voltage experts. They are soon to be joined by a third location, in Nürtingen. At the centres, employees from authorised workshops are taught how to deal properly with Volkswagen vehicles.
A Volkswagen e-Golf, with battery removed, on the lifting platform: as a rule, battery systems in modern cars can usually be repaired.
The modular structure of the battery (in picture: the battery from a Volkswagen e-up!) allows a relatively simple repair process.
Every Volkswagen service partner in Germany, of which there are currently about 1,850, accepts electric cars for services and is qualified to maintain and repair them. Across Germany, there are specific support centres, which specialise in battery repair. The German service network currently includes 265 such centres, with that number set to rise to 450 by the end of 2021. The high-voltage experts working there are trained in how to open and work in the car battery.
Battery maintenance tips from the pros
When a Volkswagen service partner accepts an electric vehicle, which they suspect may have a battery fault, they first perform a routine diagnosis. This allows them to determine important characteristics, such as the “State of Health” (SoH) of the battery. This value describes the remaining capacity – how much of the original storage capacity a battery can still provide, having been used for a number of years.
The speed at which a traction battery in an electric car loses capacity depends largely on how the battery is maintained. Rule of thumb: A battery feels most comfortable with a charge level of between 30 and 70 percent. Anyone who generally keeps their battery in this range is reducing wear. For this reason, Volkswagen electric vehicles come with software that can be used to limit the maximum charge of the battery.
Accurate diagnosis required
If the examination points to a problem with the battery, the service partner hands the vehicle over to a support centre – unless they have that status themselves. Is it a part, a control unit or a battery cell that is causing the problem? In the case of a car that has been involved in a crash, the experts also check the battery casing for deformations and leaks. If any potential risk is discovered, the car is first moved to a so-called quarantine area, where it is isolated and monitored.
The subsequent repairs depend on the result of the examination. Deformations can occur at points, at which no sensitive parts are to be found, but there are cavities – so a dent does not necessarily mean there is a technical issue. The high-voltage batteries in the ID. family also have a sandwich design. The underbody protection and cooling system protect the battery cells from below. This prevents damage to the expensive cells.
Modules can be exchanged, cells cannot
The failure of individual cells within a battery module can easily be diagnosed: if one cell fails, the capacity of the module is still 50 to 66 percent, due to the parallel wiring of the cells. Furthermore, the remaining functional cells in the module must then “work” harder. This results in them reaching a higher temperature with lower voltage. If a cell is faulty, the complete module is exchanged, according to Walther. Individual battery cells cannot be replaced. The MEB battery consists of between seven and twelve modules, depending on the size.
Costs of exchanging modules
The differences between models and specific cases mean Walther is unable to give an average price for the extensive repairs. However:
If the battery still has 70 percent or more of its capacity remaining, it is definitely worth exchanging one or two modules.
Johannes Walther
Repairs make valuable contribution on the “way to ZERO”
Thanks to energy-optimised production, the use of green electricity, and the offsetting of unavoidable emissions, the Volkswagen ID.33 and ID.44 models are already net carbon-neutral when Volkswagen hands them over to the customer.
Repairing batteries extends their service life in the vehicle, after which they are given a so-called second life, for example as a mobile energy store or domestically. The battery is basically designed for the entire life of a vehicle, with more than 95 percent of the battery able to be recycled at the end of its lifecycle. To achieve this, Volkswagen runs its own recycling facility in Salzgitter.
As part of the ACCELERATE strategy, the share of Volkswagen Passenger Cars sales generated by all-electric cars is set to rise to at least 70 percent by 2030 in Europe, and 50 percent in the USA and China.
Battery cells (1) cannot be exchanged individually. High-voltage experts are trained to remove the battery modules (2) from the battery system (3).