The graphene technology developed by the Korea Electrotechnology Research Institute (KERI, Acting President Nam-Kyun Kim) has been selected as the best national research and development technology, and is expected to be widely utilized in mobility batteries and electrical components in the future.

The achievement of 'Development of Metal/Graphene Composite Electrodes for Future Mobility Batteries and Electrical Components' by the Electrical Materials Research Division of the Electric Power Research Institute was named one of the '100 Best National Research and Development Achievements of 2022'.

In addition, its value was further recognized by being selected as the best (machinery and materials sector), out of which only 12 out of 100 were selected.

This achievement, which is attracting much attention in the next-generation E-mobility field, is largely composed of ‘high-capacity silicon/graphene composite cathode material technology for lithium-ion batteries’ and ‘low-cost copper/graphene composite ink technology for electrical components.’

The 'high-capacity silicon/graphene composite cathode technology' is an achievement that greatly increases the possibility of commercialization by complementing the shortcomings of 'silicon (Si),' the next-generation cathode material for lithium-ion batteries, which are key components of eco-friendly electric vehicles/ships/drones/robots, etc., through the introduction of graphene.

Silicon has the advantage of having an energy density 10 times higher than that of the previously used graphite and a fast charge/discharge speed, but when charging/discharging It has the disadvantage of a volume expansion problem of up to 300% and low electrical conductivity. To solve this, KERI manufactured an ideal high-capacity cathode material for lithium-ion batteries by complexing 'graphene', which has excellent conductivity and is electrochemically stable, with silicon.

The research team has already been producing high-quality graphene with high crystallinity and electrical conductivity through research for over 10 years, and possesses a 'high-concentration paste-type graphene aqueous dispersion technology' that can be directly applied to the lithium-ion battery cathode manufacturing process.

In addition, based on this technology, they succeeded in mass-producing a composite cathode material with a core-shell structure (a method in which graphene wraps the core silicon like a shell). They also secured price competitiveness by utilizing inexpensive micron (μm)-sized silicon instead of the existing expensive nano silicon.

Experts report that if silicon/graphene composite cathode technology is applied to electric vehicles, it will be possible to increase battery performance and increase driving range by about 20%. The technology was recognized for its high level of technology and was transferred to HNS Co., Ltd. (CEO Nam Dong-jin), a company specializing in electrical and electronic materials and components, for 1.1 billion won last year, and commercialization is currently under preparation.

'Low-cost copper/graphene composite ink technology' is an ink that conducts electricity and is an essential material used in the manufacturing of various electrical and electronic device parts as well as in all aspects of our country's materials and parts industry. The characteristic of KERI technology is that it uses copper, which is 1/10 the price of existing silver, as an ink material.

Copper has a higher melting point than silver, and when exposed to air, an oxide film easily forms on its surface, which has the fatal problem of preventing electricity from flowing. However, the research team has effectively synthesized graphene on the surface of copper through a ‘liquid synthesis method’ that they developed for the first time in the world, securing a process technology that not only prevents copper from oxidizing, but also enables mass production of ink.

The significance of the copper/graphene composite ink technology is import substitution. The existing high-quality, conductive silver ink for manufacturing precision parts was imported from countries such as Japan with a dependency of as much as 95%, but with this KERI-developed technology, it has become possible to establish a foundation for import substitution as well as self-sufficiency in materials and parts. The related technology was also transferred to Daesung Metal Co., Ltd. (CEO Noh Yoon-goo), a metal material and ink manufacturing specialist, for 550 million won, and mass production has already been achieved, and copper/graphene ink is currently being used to make display and mobility battlefield wiring.

KERI Electric Materials Research Center Director Lee Geon-woong, who is in charge of the research, said, “Our achievement will greatly contribute to securing quality and reliability as well as realizing technological independence in important new electric materials and parts in the future mobility field with very high added value.” He added, “I am very pleased to be selected as one of the top 100 national R&D excellence achievements as it recognizes the value of our efforts and technology.”

KERI added more meaning to this year's list of 100 National Research and Development Excellence by including 'Linear Accelerator and Magnetron Technology for Radiation Cancer Treatment (Research Director Kim Jong-il, Director of the Electromagnetic Wave Application Research Center)'. The technology is a core medical technology that converts the electric energy of electron beams generated in a vacuum space into high-power electromagnetic wave energy and treats cancer by emitting high-energy radiation. It has received much attention as an achievement that has realized the domestic production of radiation cancer treatment technology, which had previously been entirely dependent on imports.

Meanwhile, the 100 Best National R&D Achievements have been held annually since 2006 to enhance the public's understanding and interest in the role of science and technology in driving national development, and to encourage pride among scientists and engineers. The achievements selected this year will be awarded a certificate and plaque from the Minister of Science and ICT, and will receive additional points in business and institution evaluations according to relevant regulations, and will also be published and distributed as a casebook.