The Korea Electronics Technology Institute (KETI, President Shin Hee-dong) has developed a technology that increases the energy density of all-solid-state batteries while ensuring safety, which is expected to significantly contribute to reducing the risk of electric vehicle fires in the future.

KETI announced on the 5th that it had successfully developed a lithium metal protective layer technology that increases the energy density and stability of all-solid-state batteries together with the team of Professor Yoo Dong-ju of Korea University and the team of Professor Yoon Won-seop of Sungkyunkwan University.

All-solid-state batteries, unlike conventional lithium secondary batteries, are composed of solid electrolytes, so they are safe and have the advantage of high energy density, eliminating the risk of explosion. Therefore, there is currently fierce national R&D competition for commercialization of the technology.

Among them, lithium metal anodes are the optimal material with higher energy density than existing graphite anodes, but they have problems such as side reactions occurring between the electrolyte and lithium metal, and dendrites forming on the surface of the anode during charging, which increases the risk of fire such as battery explosion and reduces the battery lifespan.

KETI's Next-Generation Battery Research Center (Director: Ji-Sang Yoo) developed a lithium metal protective layer with high ionic conductivity using nanoparticle silicon powder, ultimately improving the output performance of lithium metal all-solid-state batteries.

According to Researcher Lee Geung-jong and Dr. Choi Seung-ho (senior researcher) who led the technology development, nano-sized silicon powder It was confirmed that the composed protective layer can effectively suppress dendrite growth on the cathode surface by forming lithium metal and a silicon-lithium alloy.

Furthermore, the alloy protective layer technology developed through this study was applied to the manufacturing process to ensure safety in high-output environments, and the commercial viability of the technology was proven through pouch-type cell verification.

The research results were published in the latest issue* (published in August) of ACS Energy Letters (IF=19.3), a renowned international academic journal in the field of energy chemistry.

KETI Next Generation Battery Research Center Director Yoo Ji-sang (corresponding author) said, “In order to increase the energy density of all-solid-state batteries, the application of lithium metal anodes is essential, but the lithium dendrite phenomenon has been a major obstacle to battery development.” He added, “The lithium metal protective layer technology developed by KETI researchers is expected to become a key technology for improving the performance of all-solid-state batteries as it can be applied to large areas in the future.”

Meanwhile, this research result was developed through the Automotive Industry Technology Development Project supported by the Ministry of Trade, Industry and Energy and the Korea Institute of Industrial Technology Planning and Evaluation, and the STEAM Research Project promoted by the Ministry of Science and ICT and the National Research Foundation of Korea.