Incheon Benz Electric Vehicle Fire Cause Remains Unidentified

Possible External Impact on Electric Vehicle Battery Pack Confirmed to Cause Fire
Benz Korea and German Headquarters Investigated but Battery Defect Not Confirmed
Apartment Manager Charged with Negligent Injury in Duty

The cause of the electric vehicle fire that occurred in the underground parking lot of an apartment in Cheongna International City, Incheon, last August has not been determined despite a four-month police investigation.

On the 28th, the Criminal Mobile Unit of the Incheon Metropolitan Police Agency announced that they plan to send four individuals, including employee A from the management office of an apartment in Cheongna International City, to the prosecution without detention on charges of negligence causing injury. A and others are suspected of failing to properly manage safety during the Mercedes-Benz electric vehicle fire that occurred on August 1 in the underground parking lot of an apartment in Seo-gu, Incheon, causing injuries to residents and others. Among them, A, who was on night duty, was found to have pressed the stop button immediately after the fire broke out, preventing the sprinkler system from activating.

A Mercedes-Benz electric car reduced to its frame by fire following an explosion in the underground parking lot of an apartment complex in Cheongna International City, Seo-gu, Incheon last August. Photo by Yonhap News

As a result, 23 residents and others inhaled smoke or complained of dizziness and received hospital treatment, with 87 vehicles burned and 783 vehicles scorched, causing significant damage. Among the 23 who inhaled smoke, three submitted injury medical certificates to the police. In the police investigation, A stated that "if alarms malfunction, apartment residents might protest, so I turned off the sprinkler first."

The suspects also include the apartment management office head and the overall fire safety manager. The police judged that they bear responsibility for the fire as they either failed to respond properly initially or did not adequately manage safety on a regular basis. It was found that they did not conduct fire response education or training for employees regularly.

The police formed a dedicated team led by the head of the Criminal Mobile Unit and investigated for four months but ultimately failed to identify the exact cause of the fire. During this period, the police conducted raids at four locations, including the Mercedes-Benz Korea Seoul office, and carried out joint forensic examinations three times. The National Forensic Service suggested that the fire might have started due to external impact damage to the lower part of the battery pack of the Mercedes-Benz electric vehicle or electrical heating caused by 'insulation breakdown' (a phenomenon where the insulator loses its properties) inside the battery pack.

The police explained that some vehicle experts also expressed opinions that the fire might have been caused by damage to the electric vehicle battery cells due to external impact, but since the battery management system (BMS) was completely burned, the exact cause of the fire could not be confirmed. As no inherent defect in the electric vehicle battery was identified, Mercedes-Benz Korea and the German Mercedes-Benz headquarters avoided criminal charges. The police also summoned officials from Mercedes-Benz Korea and the German Mercedes-Benz headquarters as witnesses but found no grounds for criminal indictment. A technician from the German Mercedes-Benz headquarters reportedly stated during the police investigation that "there was no problem with the battery itself" and "we do not know the exact cause either."

A police official said, "The battery of the electric vehicle that caught fire is a component made by receiving battery cells from a Chinese company and assembling the battery pack with their own technology before installing it in the vehicle," adding, "There was no driving history that could have caused external impact to the underside of the vehicle, and there was no recall history for other reasons." He continued, "The sprinkler would have worked properly if it had not been deliberately turned off," and explained, "Because the response after the fire was inadequate and the damage increased, charges of negligence causing injury were applied to the related parties."