SK On’s ESS Passes Large-Scale Fire Test... “No Thermal Runaway in Adjacent Containers”

[Financial News] SK On said on the 28th that its energy storage system (ESS) had completed a large-scale fire test and met the evaluation criteria under UL 9540A, the North American standard for ESS fire safety testing. The company said that thermal runaway did not spread to adjacent containers during a test that recreated an actual fire.
UL 9540A is a leading North American ESS safety testing standard that assesses how much heat spreads to the surrounding area when thermal runaway occurs in a battery. The large-scale fire test (LSFT), in particular, recreates an actual ESS fire to verify, among other things, whether fire spreads to adjacent containers. In March this year, its detailed requirements were strengthened to assess factors such as fire spread against clearer criteria.
According to SK On, the test results showed that heat from the ESS container where the fire began did not cause thermal runaway in the battery cells inside the neighboring container. The temperature inside the container also met the evaluation criteria.
An SK On representative explained, “We designed the system to release the heat generated by the ESS gradually over an extended period, curbing a sharp rise in the heat release rate and reducing the likelihood of fire spreading to nearby containers.”
SK On plans to use the UL test report to accelerate its push into the global ESS market. It signed a contract last August to supply lithium iron phosphate (LFP) batteries for ESS with U.S. ESS company NeoVolta Power, and in September last year it signed a contract with U.S. renewable energy company Flatiron to supply 1 GWh of ESS.
It is also stepping up efforts in the domestic market. At the second Central Contract Market held in February this year, it secured 284 MW, more than half of the total 565 MW. The Seosan plant in South Chungcheong Province is converting 3 GWh of its total 7 GWh production capacity into a dedicated line for LFP batteries for ESS.
An SK On representative said, “This test confirmed the fire safety of SK On’s ESS, which suppresses fire spread and maintains key safety performance even under actual fire conditions.” The representative added, “We will continue to strengthen our safety technology and product competitiveness, provide customer-tailored ESS solutions, and expand our presence in global markets.”
[email protected] Kim Dong-chan Reporter