The Korean government has concluded that faulty batteries were the main culprit behind the recent spate of energy storage system (ESS) fires.
The ESS Fire Accident Investigation Team announced the outcome of its second investigation in the fires on Feb. 6.
The conclusion is opposite to the one announced after the first round of investigation in 2017. At the time, the team put the blame on the poor operation of ESS facilities. The latest conclusion will undermine the reliability of batteries manufactured by Korean companies.
The investigation team investigated the five ESS fire accidents that took place since August last year. It said in a briefing at the Government Complex in Sejong City that four of the five cases were caused by faulty batteries. The four fires took place at business sites in Yesan of South Chongcheong Province, Pyeongchang of Gangwon Province, Gunwi of North Gyeongsang Province and Gimhae of South Gyeongsang Provicnce. The sites in Yesan and Gunwi used batteries manufactured by LG Chem, while those in Pyeongchang and Gimhae sites used batteries from Samsung SDI.
The government launched an investigation team after a total of 23 ESS fires occurred for 1 year and 9 months from August 2017.
The head of the second investigation team explained why his team arrived at a conclusion different from that of the first probe.
“After the first investigation, the government authorities has made it mandatory for ESS operators to keep battery operating data separately," said Kim Jae-chul, a professor of electrical engineering at Soongsil University, who led the second investigation team. “This made it possible for us to analyze data on battery failures during the second investigation.”