Energy-dense anode-free rechargeable lithium metal batteries based on thick cathodes and pulse charging strategies

Abstract

Anode-free lithium metal batteries (AFLMBs), developed from lithium metal batteries (LMBs), have shown significant advantages in energy density, the assembly process, safety, and cost. However, continuous consumption of the Li anode without sufficient supplements leads to rapid capacity decay of AFLMBs. In this work, we propose that through increasing the loading of cathodes, the assembled AFLMBs demonstrated not only increased energy density but also prolonged cycling life, which were attributed to the flat and compact Li deposition at high areal capacity. In addition, by using pulse charging strategy, the depletion of Li-ion was able to compensate and the solid electrolyte interphases could be repaired, enabling the batteries with reduced polarization at high current denstiy (5 mA cm⁻²) and a capacity retention of 79.4% after 50 cycles. Our results put forward feasible and facile approaches to build energy-dense AFLMBs.