Fires blamed on battery makers

The government clashed with Korea’s two largest battery makers Thursday over investigation results attributing fire breakouts at energy storage systems to the companies’ battery cells.

The investigation found that four out of five energy storage system fires that broke out after August 2019 started from faulty battery cells, a committee of experts backed by the Ministry of Trade, Industry and Energy announced.

The systems are composed of multiple battery cells and are used in factories or renewable energy plants such as wind farms to store power and act as a stable power source.

The government’s explicit finding that LG and Samsung’s batteries caused the fires could be a serious blow to their business. The two companies have already invested large sums of money to enforce safety measures in its battery cells to regain trust.

Thursday’s announcement contradicted the government’s initial round of investigation last June, when the committee cited improper management and installation as the main reasons for 23 energy storage system fires from mid-2017 through 2018.

The latest investigation looked into five additional energy system fires that happened after last August.

“Operational records of the system, battery and monitoring results helped us better define the relationship between the battery cells and the fire,” said Kim Jae-chul, the committee’s co-head on Thursday.

He added that the first investigation lacked access to the same amount of information because the facilities had all burned down.

“Our assumption is that faulty batteries and a common practice of keeping a high state of charge level caused the four fires,” said Kim, referring to the level of charge a battery has relative to its capacity. According to the committee, the four systems in question kept the figure above 95 percent.

One system that had a fire unrelated to batteries was caused by the system’s exposure to an external substance, the committee found.

The report pointed to traces of damage to battery parts, along with monitoring records that suggested the fire had started from the battery cells in four cases.

Among the four, two each were supplied by Korea’s two largest battery makers: LG Chem and Samsung SDI. Both challenged the committee’s investigation results in lengthy documents Thursday afternoon that countered the government report clause by clause.

The companies both offered strongly worded statements that they do not believe that the battery cells had a direct causal relationship with the fires.

Both companies argued that traces of fusion do not prove the fires started from the battery cells.

“Fire requires a combination of three conditions - the ignition source, oxygen and fuel. A battery can provide energy [and the fuel] but cannot in itself be an ignition source,” Samsung SDI argued in the statement.

The company also argued against the fact that the committee’s investigation did not consider the actual fire locations but instead examined batteries from other systems that were produced at a similar time.

LG Chem and Samsung SDI have been conducting internal investigations on their own. Since the fire outbreaks, both companies have repeatedly said that the domestic fires are the result of mismanagement by the energy system operators. They also export energy storage system battery cells overseas, but none have burst into fire outside Korea.

BY SONG KYOUNG-SON [song.kyoungson@joongang.co.kr]