Diphenyl Azidophosphate as a Functional Electrolyte Additive for High-Conductivity Film Construction over Lithium Metal Battery

摘要

Lithium metal batteries (LMBs) with high loading and high current density can be achieved by tailoring electrolyte components. As an effective film-forming electrolyte additive, diphenyl azidophosphate (DPPA) has been proposed here to construct high conductive solid electrolyte interphase (SEI) layers on the Li metal anode surface enriched with Li3N and P-O compounds. Compared with cells without DPPA additive, the Li divide divide Cu cells with 1% DPPA demonstrate evaluated accurate Coulombic efficiency (CE) from 77.9% to 93.8%, and Li divide divide Li symmetric cells are able to cycle for more than 250 h at the current density of 2 mA cm(-2). The high conductive SEI layer increases the exchange current density of Li metal anode from 0.247 mA cm(-2) to 0.760 mA cm(-2). The Li divide divide LiNi0.8Co0.1Mn0.1O2 (NCM811) cell maintain 80.8% capacity retention after 250 cycles in the DPPA-containing electrolyte. Discharge capacity of the Li divide divide NCM811 cell can reach 142 mA h g(-1) at a high discharge current of 13.2 mA cm(-2). Further theoretical calculations indicate that the DPPA additive can be preferentially reduced to form a stable SEI layer with high conductivity.

关键词