A few details are important when the accident vehicle is appraised by an expert - examples:

• Electrical know-how: Motor vehicle experts need basic electrical knowledge. Among other things, they must know where the high-voltage power cables run in the car and check these cables for their integrity.
• Battery in view: The battery check after an accident is similarly important. So-called lithium-ion batteries are used in electric cars and must not be damaged. Otherwise they pose a fire and explosion hazard.
• Know the additional repair costs: In addition, it plays a role for the expert opinion that the repair workshop should later observe various safety regulations. This increases the repair costs. The assessor must of course include these additional costs in his report, because the injured party benefits from this.
• This may also include Working under voltage should not be underestimated: the risk assessment, the handling of intrinsically and non-intrinsically safe high-voltage systems, knowledge of the structure of the drive batteries and the entire vehicle body, high-voltage diagnostics, safe working on the electric car.

Roads Test of the Porsche Taycan

The ones who suffer are the customers. BMW sees the responsibility primarily with the supplier of the EGR cooler, but is anything but accommodating in legal proceedings. The burden of proof after a vehicle fire lies with the owner of the vehicle: he must prove the technical defect to the manufacturer in each individual case (despite the KBA recall). Without a lawyer's complaint and an expensive expert, nothing is possible, because BMW takes the position that not all radiators are affected. Nevertheless, the cause of the fire is usually easier to clarify in the case of combustion engines than in the case of battery cars - if only because the experts have much more experience with conventional drives. According to Korean media reports, Hyundai and LG Chem are still arguing about the cause of the 14 battery fires in the Kona EV so far (according to the manufacturer, no vehicle in Germany has been affected yet). The KBA recall cited at the beginning of this article also leaves room for interpretation. The only thing that is clear is that the cells "breathe" during charging and discharging, i.e. they expand and shrink minimally. The smallest impurities in cell production can rub through the separating layer between the positive and negative pole (anode) in places. It is also possible that these mechanical stresses lead to contacting problems and short circuits in LG Chem's flexible pouch cells.

Flare up through the battery

Modern electric vehicles have so-called battery management systems that are intelligent enough to recognise short circuits, to recognise faults, so that a fire development by itself is relatively unlikely and can rather only occur through external influences, i.e. an accident, for example. But even then, the fire development, the heat released, is not significantly different. We have a second peak, because if you imagine a time course of heat release and temperature, then we have a second high point, which is caused by the burning of the accumulator. In addition, toxic gases are a problem. And then we have another difference: we can't put electric vehicles on a par with electric vehicles because the batteries are also constructed differently. Some of them have different cell chemistries, and we have also seen a tremendous development in this area in recent years. It is true that toxic gases are released, and that can be a problem for the firefighters.

Exciting literature on the subject of e-mobility