Lower Interfacial Resistance between a Ta-Doped Li7La3Zr2O12 (LLZTO) Solid Electrolyte and NiCl2 Cathode by a Simple Heat Treatment for a High-Specific Energy Thermal Battery

Min Yang; Licai Fu; Jiajun Zhu; Wulin Yang; Lingping Zhou

doi:10.1021/acsami.2c14067

Lower Interfacial Resistance between a Ta-Doped Li₇La₃Zr₂O₁₂ (LLZTO) Solid Electrolyte and NiCl₂ Cathode by a Simple Heat Treatment for a High-Specific Energy Thermal Battery

ACS Appl Mater Interfaces. 2022 Nov 23;14(46):52467-52475. doi: 10.1021/acsami.2c14067. Epub 2022 Nov 8.

Authors

Min Yang¹, Licai Fu¹, Jiajun Zhu¹, Wulin Yang¹, Lingping Zhou¹

Affiliation

¹ College of Material Science and Engineering, Hunan University, Changsha410082, China.

PMID: 36346367
DOI: 10.1021/acsami.2c14067

Abstract

Large current discharge is restricted because of the poor conductivity between the Ta-doped Li₇La₃Zr₂O₁₂ (LLZTO) solid electrolyte and electrode. The poor conductivity would be caused by the interfacial reaction between LLZTO and the cathode, which is detrimental to the secondary Li ionic or metal battery. In this case, we studied the interfacial reaction between LLZTO and a haloid cathode (NiCl₂) for a thermal battery for the first time, and a lower interfacial resistance could be obtained by a simple heat treatment. Owing to the element interdiffusion of Cl^- and O^2- at a high temperature of 600 °C, the main reaction products are LaOCl, LiCl, and La₂Zr₂O₇. This reaction reduces the interfacial resistance from 3 Ω to 2 Ω. After a pretreatment at 600 °C, the discharge specific energy could reach 1254 Wh kg^-1 from 828 Wh kg^-1 at 550 °C with a cut-off voltage of 1.8 V. These results suggest that the interfacial reaction could be significant for the battery by adding interfacial contact. It is an effective approach to decrease the interfacial resistance at high temperature for some specific system, such as a haloid cathode-solid electrolyte.

Keywords: LLZTO; NiCl2 cathode; interface reaction; resistance; thermal battery.