ESS units caught on fire due to bad management

SEJONG - A government-backed committee of experts blamed a series of fires that ravaged energy storage systems (ESS) over the past two years on faulty components and poor safety practices in the budding industry.

The Ministry of Trade, Industry and Energy announced Tuesday that after a five-month investigation, the committee of experts found four causes for the fires: defective battery protection systems, improper operation management, faulty installation of the systems and a lack of an overall control unit.

The committee also found manufacturing defects in the battery cells of the ESS units but said it failed to recreate fires through tests based solely on the defective batteries.

An ESS, largely composed of batteries, is used in factories or eco-friendly power plants such as wind farms to store power and acts as a stable power source.

Since August 2017, there have been 23 ESS-related fires, leading to the investigation late last year.

The committee explained that it recreated the circumstances of the fires to find the causes.

It found that some ESS battery protection systems failed to function properly during electrical surges, causing components to explode.

The committee said ESS units located on mountains or near beaches were susceptible to condensation and dust, and systems that were not managed properly were prone to fires as components would degrade.

The expert panel also discovered that systems that were not installed properly, such as those that did not appropriately store batteries, could burst into flames.

Lastly, the committee found that the lack of an overall control system that connects ESS components such as batteries and power conversion systems contributed to the failures.

The government said it will change regular safety inspection periods to one to two years from the current four years, and conduct random special checks.

The committee refrained from placing direct responsibility on specific parties such as battery manufacturers.

“The investigation committee is focused on finding the cause of the accidents, not finding who is responsible,” said Kim Jung-hoon, an electrical engineering professor at Hongik University who headed the committee. “Battery manufacturers, system integrator companies and power conversion system companies are all at fault.”

The Trade Ministry added that the fires were not caused by regulation violations and were not subject to punishment by the government.

The investigation weighed heavily on the local battery industry after the government recommended businesses halt operations of ESS late last year.

Major battery maker Samsung SDI reported a 52.2 percent on-quarter decline in operating profit for the first quarter, blaming the slump in the ESS market. Sales from its battery business fell 7.9 percent over the same period.

LG Chem, another battery maker, recorded a 57.7 percent on-year decline in operating profit in the first quarter. Its battery business sales fell 20.5 percent on quarter with the company blaming the ESS fires.

The industry was upbeat about Tuesday’s report. “We are relieved that battery cells were not found to be the cause,” said LG Chem in a statement. “As the government announced that it will designate batteries to be mandatorily managed for safety, we will follow the set safety standards.”

BY CHAE YUN-HWAN [chae.yunhwan@joongang.co.kr]