A technology has been developed that dramatically suppresses performance deterioration of thick-film electrodes by introducing a roll-to-roll compatible flash process for the first time in the world to manufacture secondary battery electrodes. The technology offers new possibilities for reducing the cost of batteries, increasing their energy density and capacity, while reducing their size and weight.

The research team of Senior Researchers Woo Kyu-hee and Kwon Shin of the Secondary Battery Equipment Laboratory at the Korea Institute of Machinery and Materials (President Ryu Seok-hyun) under the Ministry of Science and ICT has developed an electrode activation technology that suppresses the deterioration of thick-film electrodes by utilizing an ultra-high-speed, large-area flash process.

The research team also successfully demonstrated compatibility with roll-to-roll processes through a pilot-scale roll-to-roll test bed.

Thick film electrodes can achieve high energy density, simplify the structure by reducing the number of layers in the battery pack, and dramatically reduce costs by improving the efficiency of the manufacturing process.

On the other hand, there was a problem that the thick electrode thickness increased the resistance to the movement of lithium ions and electrons and made electrolyte penetration difficult, which resulted in a deterioration in electrochemical performance such as rate characteristics and lifespan.

To address this issue, the research team applied a brief flash of less than a millisecond to the thick electrode.

The photothermal reaction occurring during this process immediately causes reactions such as carbonization of the material, expansion of the interlayer spacing of the active material, increase in porosity, and expansion of the interfacial area with the electrolyte, thereby enhancing the mobility of lithium ions and electrons and improving electrolyte permeability.

As a result, the performance deterioration of the thick film electrode could be suppressed.

Since it utilizes a photothermal reaction, it prevents the entire electrode from being exposed to high temperatures, thereby minimizing binder decomposition inside the electrode and preventing thermal damage such as oxidation of the current collector.

This technology is highly compatible with the roll-to-roll process, which is the standard in the secondary battery manufacturing industry, and is expected to be widely applied to various electrodes, including nickel-cobalt-manganese cathodes.

The research team is conducting an applicability evaluation by applying the flash process to the electrode drying process.

jeonIt was confirmed that the energy consumed and process time for extreme drying can be significantly reduced while inducing electrode activation effects.

Recently, we are developing mass production-level equipment and conducting process evaluations in cooperation with secondary battery equipment companies.

Kyu-hee Woo, a senior researcher at the Korea Institute of Machinery and Materials, said, “The electrode activation technology using flash is a post-processing technology that is compatible with the roll-to-roll process, so it is relatively easy to integrate into existing processes and manufacturing facilities.” He added, “We plan to continuously conduct tests, evaluations, and verifications to improve the perfection of the technology, with the goal of entering the domestic secondary battery manufacturing industry.”

This study was conducted with the support of the Global Top Strategy Research Group of the Ministry of Science and ICT and the Carbon-Reducing Medium and Large Secondary Battery Innovation Manufacturing Technology Development Project of the Ministry of Trade, Industry and Energy.

In recognition of its excellence, it was selected as the cover paper for the February 2025 issue of Small Methods (IF: 10.7), an international academic journal in the field of materials and chemistry.