Thermal runaway in modified e-bike caused deadly Nanjing fire

A thermal runaway triggered the fire that broke out in Nanjing's Mingshangxiyuan community on Feb 23, which claimed 15 lives and injured 44, according to an investigation report released by Jiangsu Fire and Rescue on Wednesday afternoon.

The investigation, led by the provincial government, concluded that the fire was caused by thermal runaway in an illegally modified electric bicycle's oversized lithium-ion battery.

The report stated that the battery of the vehicle which was parked in a building's open-air space, overheated and eventually caught fire.

The flames quickly spread to nearby bicycles and flammable materials stored illegally in the courtyard. The toxic smoke and intense heat penetrated into residential units, leading to casualties.

The investigation also revealed that the bike owner had illegally modified the vehicle and purchased an oversized battery from unregulated online sources. The manufacturer and retailer of the electric bicycle were found to have violated national safety standards.

Contributing factors included poor maintenance of firefighting equipment and the property management company's failure to quickly detect the fire, evacuate residents or take effective emergency measures.

As per the investigation, 10 individuals, including the bike owner, unlicensed battery sellers and the property management company's executives, have been subjected to criminal coercive measures by the public security authorities, in accordance with the law.

In addition, seven enterprises involved in electric bicycle production, sales and property management face penalties from regulatory authorities.

Liu Boqian contributed to this story.