Onset Potential for Electrolyte Oxidation and Ni-Rich Cathode Degradation in Lithium-Ion Batteries.

ABSTRACT: High-capacity Ni-rich layered metal oxide cathodes are highly desirable to increase the energy density of lithium-ion batteries. However, these materials suffer from poor cycling performance, which is exacerbated by increased cell voltage. We demonstrate here the detrimental effect of ethylene carbonate (EC), a core component in conventional electrolytes, when NMC811 (LiNi_0.8Mn_0.1Co_0.1O₂) is charged above 4.4 V vs Li/Li⁺-the onset potential for lattice oxygen release. Oxygen loss is enhanced by EC-containing electrolytes-compared to EC-free-and correlates with more electrolyte oxidation/breakdown and cathode surface degradation, which increase concurrently above 4.4 V. In contrast, NMC111 (LiNi_0.33Mn_0.33Co_0.3

SUBMITTER: Dose WM 

PROVIDER: S-EPMC9578037 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature