A fire at a lithium battery manufacturing plant in Hwaseong, South Korea, on Monday killed at least 23 people and injured eight others.

Parts of the top floor of the facility - operated by battery manufacturer Aricell - collapsed, and chunks of concrete spilled into the road. The warehouse stored approximately 35,000 battery units, according to fire officials.

The fire - video of which has appeared on social media - was apparently triggered by a series of explosions and burned for 22 hours before it could be extinguished, according to information posted by Korea's National Fire Agency. Other reports suggest the blaze was largely under control within six hours.

The majority of the victims were foreigners - at least 18 of them Chinese. The deceased were found on the second floor of the building in which the fire broke out, and were likely in the process of inspecting and packaging batteries.

As the workers were largely temporary hires, it is believed they may not have been familiar with the structure of the building. This probably contributed to their deaths, likely caused by inhaling the toxic smoke generated by burning batteries. Fire officials were only able to find some victims by reportedly geolocating their mobile phone signals.

The CEO of Aricell, Park Soon-kwan, apologized for the accident and promised to "provide sincere support to the deceased and the bereaved families in all possible ways." The CEO also pledged to "make every effort to investigate the cause of the accident and take follow-up measures to prevent recurrence."

As there are concerns that the hazardous chemicals from the batteries could contaminate the surrounding areas, the mayor of Hwaseong has proposed declaring the area a special disaster area. And the Ministry of the Interior and Safety announced it will urgently provide a ₩1 billion ($720,000) grant to Hwaseong for damage repair and debris disposal.

What next?

The Central Disaster and Safety Countermeasures Headquarters met to discuss supporting fire victims and prevent future occurrences.

And Korea's National Fire Agency announced on Tuesday it will investigate the safety management status of 213 workplaces that store substantial amounts of battery products - checking for storage and handling compliance as well as emergency procedures and fire safety education for employees.

Founded in 2020 and based in Hwaseong, Aricell specializes in manufacturing and exporting lithium-thionyl chloride (Li-SOCl₂) batteries - particularly for sensors and radio communication devices.

The batteries are known for their high energy density, long shelf life, and wide operational temperature range - but equally for being particularly reactive.

One of the world's most respected battery tech scientists, Dr Rachid Yazami, told The Register the batteries are known for using a liquid cathode, where all other chemistries use a solid state cathode.

"Thionyl chloride (SOCl₂) is a highly reactive liquid. When combined with water, it forms toxic gases such as hydrogen chloride (HCl) and sulfur dioxide (SO₂)," said Yazami.

Although the cause of the fire is unknown, Yazami suggested that a chain reaction could have occurred - if one battery were to experience a thermal event, it could easily propagate to others in close proximity. ®

https://www.theregister.com//2024/06/25/aricell_plant_fire_korea/