Three-dimensional SEI framework induced by ion regulation in toroidal magnetic field for lithium metal battery

Abstract

Lithium metal batteries are considered to have great potential as rechargeable batteries in next-generation energy storage devices. However, the generation of dead lithium and lithium dendrites caused by the rupture of the solid-electrolyte interphase (SEI) during cycling limits the application of lithium metal batteries. While tremendous efforts have been devoted to modification of SEI, the long-term and stable use of residual SEI has rarely been studied. Herein, we design a LiF-rich three-dimensional SEI framework (3DSF) formed in a toroidal magnetic field. This 3DSF can induce the uniform bottom-up deposition of lithium metal in the channel structure and realize 1,300 cycles at a high current density of 50 mA/cm2. The capacity of the battery paired with a high mass-loading LiFePO4 cathode (18.3 mg/cm2) maintains 98.2% at 1 C after 150 cycles. This work provides a simple and practical strategy for the additive free development of lithium metal battery technology.