Investigation of Spent Batteries Cathode Materials as Fuel Electrode for CO2 Electrolysis in Solid Oxide Electrolysis Cells

Abstract

With growing demands for carbon neutrality and the increasing challenge of spent lithium-ion battery disposal, the recovery and reuse of battery materials for electrochemical energy conversion applications has emerged as a promising strategy. The feasibility of utilizing NCM （NiCoMn） cathode materials recovered from spent lithium-ion batteries as fuel electrodes for SOEC-based CO₂ electrolysis was investigated. Electrolyte-supported cells with an LDC buffer layer and LSGM electrolyte were fabricated using a post-sintering process to suppress interfacial secondary phase formation, with the electrode sintering temperature optimized at 1250 ℃. Under FC mode with H₂ （3 vol.% H₂O） at 800 ℃, NCM/GDC achieved a maximum power density of 1.05 W·cm-2 （800 ℃）, comparable to Ni/GDC; under EC mode in CO₂ atmosphere at 1.5 V, NCM/GDC yielded 1.48 A·cm-2, outperforming Ni/GDC 1.28 A·cm-2 （800 ℃）. EIS and DRT analysis confirmed reduced polarization resistance in CO₂ adsorption, dissociation, and desorption processes, and 100-hour stability tests at 700 ℃ and 0.5 A·cm-2 demonstrated comparable degradation rates with suppressed nickel particle coarsening relative to Ni/GDC. These findings suggest that spent battery cathode materials represent a viable fuel electrode candidate for CO₂ electrolysis in SOEC systems, offering a pathway toward simultaneous waste resource valorization and electrochemical carbon conversion. MS/EN 20241186 Seunghyeon Hong （홍승현）. Investigation of Spent Batteries Cathode Materials as Fuel Electrode for CO2 Electrolysis in Solid Oxide Electrolysis Cells （폐배터 리 양극재 기반 연료극을 활용한 고체산화물 전해전지（SOEC）의 전기 화학적 CO2 전환 특성 연구）. Department of Environment and Energy Engineering. 2026. 87 p. Advisor: Prof. Jong Hoon Joo.