South Korean SK expands lithium diaphragm production in China and Poland, production capacity will reach 2.73 billion tons in 2024

According to SK, the global market demand for lithium-ion battery separators will grow from about 4 billion square meters in 2020 to about 16 billion square meters in 2025, and there is expected to be a supply shortage from 2023.

Battery network noted that since the beginning of this year, SK innovation's materials subsidiary SKIE Technology (, hereinafter referred to as: SKIET), is busy with diaphragm capacity expansion based on market demand.

On April 13th, SKIET announced the start of commercial operation of its second battery separator plant in Changzhou, China. After the formal commercial operation of the first factory in Changzhou in November last year, SKIET opened the second factory in Changzhou five months later, speeding up the pace of entering China's electric vehicle battery market.

It is reported that the second plant of SKIET Changzhou has a total production capacity of 340 million tons, and now it has partially started a production capacity of 170 million tons. Including the 340 million tons of production capacity owned by the first plant, the diaphragm capacity in China alone has reached 510 million tons, which is equivalent to the amount of diaphragm needed to produce about 500000 high-capacity electric vehicles every year. The remaining production line of the second factory aims to start in the first quarter of next year, and production preparations are being carried out smoothly.

China is the world's largest market for electric vehicles, accounting for about 50 per cent of the global market, according to SKIET. Aiming at the market prospect of China, the company will use it as the first overseas production base and will begin to build a factory in 2019. The diaphragm produced by the company is also very popular in the Chinese market, and all the supply contracts for this year's production volume have been completed before the second plant in Changzhou is officially put into production.

In addition to rapidly increasing the size of the Chinese market, in March, SKIET said in its investment decision that it would invest 1.1 trillion won (US $983.4 million) to build its third and fourth battery separator plants in Silesia, Poland. The two battery diaphragm plants have an annual production capacity of 430 million square meters. The project will increase the total capacity of SK's battery diaphragm in Poland to 1.54 billion square meters, including 680 million square meters for plants 1 and 2 under construction. Construction of Poland's No. 3 and No. 4 plants will begin in the third quarter of this year and will be put into production by the end of 2023.

SKIET said that after the opening of the second plant in Changzhou, the company's production capacity in South Korea, Poland, China and other production bases will reach 1.04 billion kilowatt, a milestone in the production scale of diaphragm needed to meet the needs of 1 million electric vehicles per year. Production capacity is expected to be further expanded to 2.73 billion tons by 2024.

Battery Network also noted that recently, electric vehicle battery fires are frequent, one of the reasons is caused by the diaphragm, but the SKIET diaphragm is favored by customers because there has not been a single fire so far. SKIET is also leading the market with technological competitiveness such as "successive extension" and "ceramic-coated diaphragm" that can produce high-end diaphragms.

According to data from SNE Research, a South Korean market research agency, SKIET accounted for 26.5% of the "Tier 1" wet diaphragm market last year, ranking first in the world. Tier 1 refers to the vehicle companies that lead the electric vehicle market, such as Tesla, Volkswagen, Renault Nissan, Toyota, Hyundai Kia and so on. The Tier 1 diaphragm market is the diaphragm market that supplies these enterprises. Including SKIET, only Japanese companies such as Asahi Kasei and Toray that produce high-quality diaphragms can enter.

"SKIET will provide a high-end diaphragm with excellent performance and safety, contribute to the rapid development of the global electric vehicle market, and continue to increase production capacity and technical capabilities to build a unique market-leading system," said Lu Zaishi, president of SKIET.