[Interview] "All-Solid-State Batteries Are the Inevitable Future... Solid Electrolyte Prices Will Plummet," Says Sung Dongwook, CEO of Solivis

Annual Production of 42 Tons of Sulfide-Based Solid Electrolyte
Completion and Initial Shipment at Hoengseong Plant
Solid Electrolyte Prices Down to One-Third of Last Year
"Prices Will Drop Rapidly with Mass Production System"
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Sung Dongwook, CEO of Solivis. Photo by Heejong Kang

"We have already secured land nearby for the construction of a second plant, which will be about 10 times larger than the current one."

On November 19, at the completion ceremony and initial shipment event held at the Hoengseong factory in the Ucheon Industrial Complex, Gangwon Province, Sung Dongwook, CEO of Solivis, revealed his vision for building a second plant.

Solivis develops sulfide-based solid electrolytes, which are a key material for all-solid-state batteries. Construction of the Hoengseong plant began in May last year, and after a year and a half, the facility and equipment were completed. On this day, the company held a commemorative event to deliver the initial batch to customers. About 140 people attended the event, including Kim Myunggi, Mayor of Hoengseong County.

All-solid-state batteries are next-generation batteries that use solid electrolytes instead of organic liquid electrolytes, reducing fire risk and increasing energy density. There are three types of solid electrolytes: sulfide-based, oxide-based, and polymer-based. Among these, sulfide-based electrolytes are preferred because they are flexible, easy to manufacture, and have excellent ionic conductivity.

The newly completed Solivis Hoengseong plant has the capacity to produce 420,000 tons of sulfide-based solid electrolytes annually, making it the largest facility of its kind in Korea to date.

Key attendees are cutting the ribbon at the completion ceremony and initial shipment event of Solibis' Hoengseong factory held on the 19th. Photo by Kang Heejong

The solid electrolytes produced here are supplied to sample and pilot lines of major domestic and international battery and automobile manufacturers. Previously, Solivis produced products at its central research institute's pilot facility in Hanam, Gyeonggi Province, but built the Hoengseong factory to meet increasing customer demand.

The production facility at Hoengseong, which was unveiled on this day, is a single-story structure and smaller than expected. Solivis explained that by using a wet process, the space required for a dry room could be minimized, which also reduced the costs associated with installing and maintaining a dry room.

Until now, competitors have produced solid electrolytes using a dry process. Because sulfur components generate toxic hydrogen sulfide (H2S) when exposed to moisture, large dry rooms are needed for dry processing.

The wet process involves mixing raw materials in a solvent and then heat-treating them. Traditionally, the wet process resulted in lower ionic conductivity, but Solivis claims to have increased ionic conductivity to 12 millisiemens (mS)/cm using its proprietary technology.

Sung Dongwook, CEO of Solivis (right in the photo), is guiding attendees including Kim Myunggi, Mayor of Hoengseong County (left in the photo), inside the Hoengseong factory. Photo by Heejong Kang

The biggest obstacle to the commercialization of all-solid-state batteries is considered to be their high price. Since mass production processes have not yet been developed, material companies have not achieved economies of scale, and the price of solid electrolytes remains high.

CEO Sung said, "At the beginning of last year, the price was 8 million won per kilogram, but now it has dropped to about one-third of that level. Once we begin to achieve economies of scale, prices will fall at an incredible rate." He also predicted that the price of lithium sulfide, the raw material, would "plummet" once a mass production system is established.

Solivis is targeting a price of 40,000 won per kilogram for solid electrolytes. Although this is still more expensive than the liquid electrolytes currently used in lithium-ion batteries, CEO Sung explained that solid electrolytes can also replace separators, making them sufficiently price-competitive.

CEO Sung expects that by 2027, demo versions of electric vehicles equipped with all-solid-state batteries will be introduced. He said, "It is already a given that all-solid-state batteries have been chosen as the next-generation power source. Although we are currently at the pilot stage, by 2027, automakers will gradually begin to establish mass production plans."

At the completion ceremony and initial shipment event of Solibis Hoengseong Plant held on the 19th, a sulfide-based solid electrolyte produced by Solibis is being shipped. Photo by Kang Heejong

Solivis has already secured land for a second plant so that it can expand production at any time when the all-solid-state battery market takes off. CEO Sung said, "We plan to increase production at the second plant by about 10 times compared to the current level. If we succeed in attracting Series C investment next year, we could break ground as early as October."

Solivis holds more than 100 core patents for original all-solid-state battery technologies, including its "third-generation wet synthesis mass production platform." In addition, the company is researching technologies to produce sulfide-based solid electrolytes under relaxed humidity conditions and anode material technologies based on solid electrolytes.

CEO Sung Dongwook also serves as a professor in the Department of Materials Science and Engineering at Hanyang University. Based on more than 20 years of experience in solid electrolyte technology, he founded Solivis in 2020. Solivis has raised a cumulative total of 42.2 billion won in investment through last year. This year, the company was selected as a preliminary unicorn in the Ministry of SMEs and Startups' "Special Guarantee Program" for fostering global unicorn companies, which can provide up to 20 billion won in scaling-up funds as of September.

Meanwhile, in Korea, Samsung SDI is operating a pilot plant for all-solid-state batteries, while LG Energy Solution and SK On are also conducting research and development for all-solid-state batteries. Among automobile companies, Hyundai Motor Group and Japan's Toyota Motor Corporation are developing electric vehicles equipped with all-solid-state batteries.

This content was produced with the assistance of AI translation services.