Electric cars damaged in accidents at the workshop: parking, assessment, quarantine area

As the number of electric and hybrid vehicles grows, so does the number of accident-damaged vehicles with high-voltage batteries ending up at towing services, workshops and recyclers. The DGUV has summarised its position on this in Fachbereich AKTUELL FBHM-124 "Handling high-voltage batteries" (as of September 2024). It applies to batteries from 60 to 1,500 volts DC, i.e. the scope of DGUV Information 209-093.

Why an accident-damaged vehicle has to be treated differently

Mechanical damage can trigger an internal short circuit in a lithium-ion cell. If a cell goes into thermal runaway, temperatures of up to around 1,400 degrees occur, and the reaction can spread to neighbouring cells. In a fire, toxic and corrosive gases are released, including hydrofluoric acid. Even batteries that appear to be discharged can still deliver very high short-circuit currents.

Recovery and handover

Information on towing and transport can be found in the manufacturer's operating instructions, supplemented by the rescue sheet. Before loading, the high-voltage system should be deactivated, for example by switching off the ignition, using an existing disconnection point or disconnecting the vehicle's 12-volt battery. If the fire brigade hands over the vehicle, its drive type and the measures already taken are documented. FBHM-124 recommends passing on this information at every subsequent handover to a workshop or disposal company, for example in the towing order.

Parking in a secure quarantine area

Electric and hybrid vehicles damaged in accidents are parked in a cordoned-off outdoor area, at a sufficient distance from other vehicles, buildings and combustible material. Exposed high-voltage components are covered with a weatherproof tarpaulin, and the vehicle is labelled. Minimum distances from buildings must be agreed with the building authority (Baugenehmigungsbehörde).

Critical battery systems are assessed by a person with battery expertise. According to FBHM-124, this is a high-voltage qualified person at level 3S or 3E under DGUV Information 209-093 with vehicle-specific knowledge, for example from manufacturer training. This person decides how long the system remains in the quarantine area and then reassesses it. It is only moved once they have given clearance.

What businesses should prepare

It makes sense to have an incident plan with a designated parking area, escape routes, the option of cooling with water and a qualification matrix showing who is permitted to carry out which assessment. There is not yet any generally recognised testing standard for storage cabinets and transport boxes. Their suitability must therefore be checked as part of the risk assessment. The transport of critical batteries is governed by the ADR and should be handled by a dangerous goods safety adviser.