Factory automation, lithium batteries present new fire safety challenges

Firefighters battle a blaze at a Coupang logistics center in Incheon, Tuesday. Yonhap

The dayslong fire at a Coupang logistics center in Incheon has highlighted growing fire safety challenges, as factories and warehouses become increasingly automated and reliant on lithium-ion battery-powered robots that could cause a massive explosion when heated.

This new industrial environment is raising concerns that existing safety standards may not be keeping pace.

Fire officials said one of their top priorities during efforts to contain the blaze at the site was preventing flames from spreading from the sixth floor, where the fire began, to the fifth floor, where hundreds of lithium-ion battery-powered warehouse robots were housed. They estimated the batteries had a combined capacity roughly equivalent to those used in about 20 electric vehicles (EVs).

The fire, which broke out on Saturday, was brought under initial control after about 61 hours without spreading significantly to the fifth floor and was fully extinguished on Wednesday.

The spread of physical artificial intelligence (AI) is expanding the deployment of autonomous mobile robots, automated guided vehicles and automated storage and retrieval systems (ASRS) across warehouses and factories, increasing the number of lithium-ion batteries used at industrial sites.

Coupang, Lotte, Kurly lead warehouse automation

Major retailers have already accelerated warehouse automation, with Coupang deploying AGVs at its Daegu fulfillment center, while Lotte Mart is building a robot and AI-powered fulfillment center in Busan with Britain's Ocado. Market Kurly is testing autonomous robots, while Hyundai Home Shopping has introduced robotic arms and automated sorting equipment at one of its distribution centers.

"When lithium-ion batteries are exposed to heat or impact, the separator inside can be damaged, causing a short circuit and an explosion," Lee Duck-hwan, a chemistry professor at Sogang University, told The Korea Times.

"So the lithium-ion batteries inside the fire will eventually explode, making the fire even worse."

A sign at a subway station in Seoul warns that large-capacity lithium batteries and electric scooters are not permitted on subway trains, June 30. Yonhap

Lithium-ion batteries can undergo thermal runaway when exposed to heat or physical damage, triggering a chain reaction that can repeatedly reignite fires and complicate firefighting efforts.

However, as battery-powered robots become more common in automated warehouses, fire safety standards have yet to fully address the risks posed by lithium-ion batteries.

Korea has proposed tighter rules for primary lithium batteries following the deadly fire at Aricell’s plant in 2024, but rechargeable lithium-ion batteries were excluded because of their widespread use across consumer electronics, EVs and industrial equipment.

Separately, the National Fire Agency strengthened fire safety standards for warehouses in 2024, requiring greater water storage capacity and higher-capacity sprinkler systems for new facilities. However, most existing warehouses, including Coupang’s Incheon facility, were built before the revised rules took effect and are not subject to the tougher requirements.

Experts say the fire safety measures should go beyond conventional warehouse protection, and must include dedicated battery charging areas, thermal runaway mitigation and emergency response procedures designed for automated facilities.

Lee said lower-quality batteries were generally more prone to problems and noted that the likelihood of thermal runaway rises as battery charge levels increase.

"The practical solution is to use high-quality batteries. Lower-quality batteries tend to have more problems,” he said. "And the higher the state of charge, the greater the likelihood of a battery catching fire on its own. So, if possible, keeping batteries at a lower charge level is also a way to reduce the risk.”

Officials inspect Aricell’s plant in Hwaseong, Gyeonggi Province, June 25, 2024. Korea Times Photo by Choi Joo-yeon

Lee also emphasized the need to strengthen emergency response procedures. "If a battery catches fire, the only way to stop it is to put it into a container of water," he said. "One option is to keep a large water tank at the workplace and train workers to quickly remove a battery and throw it in when it catches fire."

Following the Coupang fire, the Ministry of Land, Infrastructure and Transport said it plans to review improvements to safety rules to better reflect changing operating environments at large logistics facilities, where automation equipment has expanded and goods are stored at increasingly high density.

The ministry said a joint task force involving relevant agencies and experts would develop measures to strengthen safety management after authorities complete their investigation into the Coupang fire.

Coupang declined to comment, saying the cause of the fire has not yet been determined.

Meanwhile, some cautioned against overstating the role of lithium-ion batteries in the incident.

"In Coupang’s case (for example), the amount of lithium-ion batteries on the fifth floor was very small compared with the total amount of combustible materials in the warehouse," said Lee Young-ju, a fire safety professor at Kyungil University.

"It is difficult to say the batteries themselves would have made the fire dramatically worse.”

Lee said warehouses are inherently vulnerable because they contain large amounts of combustible goods packed into enclosed, high-density rack systems that trap heat and smoke while making it harder for firefighters to gain access.

"The key is how effectively you respond in the early stage, before the fire grows out of control," he said.

"We need to examine whether early detection and initial response systems actually worked properly and identify areas that need improvement."