Crew members and firefighters spray water over a vehicle covered with a fire blanket on a ship anchored in Incheon to practice extinguishing fires caused by electric vehicles on ships in this Aug. 18, 2023, photo. Courtesy of Ministry of Oceans and Fisheries

An electric vehicle's (EV) state of charge (SoC) should not exceed 50 percent during transportation by sea, as recommended by the Ministry of Oceans and Fisheries, Thursday, as part of efforts to prevent battery-caused fires on ships.

The recommendation has been applied on a trial basis to sea routes connecting Jeju and Ulleung islands with the mainland.

The ministry explained that a lower SoC allows more time to extinguish fires, as the thermal runaway of batteries takes longer.

"There has been an urgent need for safety measures, considering the lithium battery plant fire in June and a series of fires on car carriers overseas, which are presumed to have been caused by EVs," an oceans ministry official said.

"EV-caused fires on ships can cause heavy casualties, as it is difficult to rescue them quickly."

Additionally, the ministry has sought to ban the recharging of EVs on car ferries since earlier this year.

Fire apparatuses tailored for EV-caused fires will also be distributed to coastal car ferries gradually until the end of next year.

Crew members will be asked to get training on counteracting EV-caused fires on ships.

"We plan to develop fire extinguishing technologies optimized for ships, in order to brace for the era of EVs," the ministry official said.

The ministry had initially planned to announce the guidelines last month.

It noted that its decision to tighten its safety measures is not the result of a fire that occurred last Thursday in an underground parking garage of an apartment complex in Incheon, due to a Mercedes-Benz EQE 350 electric sedan equipped with a battery from China's Farasis Energy.

According to data sent from the ministry to Rep. Jung Hee-yong of the ruling People Power Party, the number of EVs carried by car ferries between May 13 and 19 was 1,591, up 28.4 percent from a year earlier.

The volume of export and import of EVs also rose to 253,000 tons last year from 43,000 tons in 2019.

"The government should overhaul systems and secure a budget to supply equipment counteracting EV-caused fires on ships," the lawmaker said.