New technology improves the stability of lithium battery -Lithium - Ion Battery Equipment
The key factor determining the performance of solid oxide fuel power lithium battery is the cathode, which is the place where oxidant is reduced. Generally, perovskite type oxides (ABO3) are used in the cathode of solid oxide fuel power lithium batteries. Although perovskite type oxides have high performance in the initial working process, their performance will decline over time, limiting their long-term use. In particular, the high temperature oxidation state required for cathode operation leads to surface segregation phenomenon, and the second phases, such as strontium oxide, accumulate on the surface of perovskite oxide, resulting in its performance degradation.
Professor WooChulJung from the Materials Science and Engineering Department of the Korean Academy of Sciences organized a research team. Using computational chemistry and experimental data, the team observed that strontium atoms in the perovskite electrode lattice were in a local compression state, which weakened the adhesion strength of Sr-O and promoted strontium surface segregation. Therefore, the team confirmed that the change of strain distribution of perovskite type oxides is an important reason for strontium surface segregation.
Based on the above findings, the team doped different sizes of metallic materials in the oxides, controlled the lattice strain range in the cathode materials, and effectively restrained the strontium surface segregation.
Professor Jung said: "This technology only needs to add a small amount of metal atoms during material synthesis, without any additional procedures. I hope this technology can be used in the future when developing perovskite type oxide electrodes with high resistance."