LG Electronics was responsible for the ceramic coating process of battery separators used in batteries of Hyundai’s Kona EV, TheElec has learned.
Earlier this week, South Korea’s Ministry of Land, Infrastructure and Transportation ordered a voluntary recall for Kona EV models due to the recent string of fires.
Coating in lithium-ion battery separators is a core process that determines their stability.
LG Electronics and Japan’s Toray are handling the coating process for LG Energy Solution, people familiar with the matter said.
Chinese companies such as Semcorp and Senior manufacturers the bare film, which is then coated by LG Electronics and Toray before being supplied to LG Energy Solution, they said. LG Energy Solution coats some of the batches as well, they said.
The coating work is given to LG Electronics and Toray for efficiency. Semcorp is currently the world’s largest battery separator manufacturer, beating Japan’s Asahi Kasei, which was the largest in 2019. Semcorp had an annual production capacity of 2.0 billion meter-square last year, dwarfing Asahi Kasei’s 900 million meter square and SK IE Technology’s 870 million meter-square.
Semcorp is offering bare films at US$1 per meter-square. Like other separator companies, it offers coated films to sell them at a higher rate. Coated separator prices increases to mid to late-US$1. Battery cell companies can save cost by outsourcing or coating the films themselves.
LG Energy Solution also has patents in safety-reinforced separators. It receives licensing fee for the patents from LG Electronics and Toray. Using the pair allows LG Energy Solution to procure separators that are more safer at reduced cost.
Separators account for around 20% of battery production costs, which makes price and safety of them a priority for battery cell manufacturers, one of the people said.