Hydroxypropylmethylcellulose: Functional material carrier for in-situ solid electrolyte engineering of advanced lithium metal batteries

Electrolyte engineering strategies with convenient operation and conspicuous effect have been launched a lot for rechargeable lithium metal batteries (LMBs). However, something profitable for LMBs’ comprehensive performance is confined to its noxious reactions with the reactive lithium metal anode. Here, for the first time, a concept of functional material carrier is proposed. Due to the excellent H2O-anchoring and film-forming capacity, hydroxypropylmethylcellulose is designated as a H2O-carrier for decorating the hydrophobicity of polyolefin separator and promoting the in-situ polymerization of liquid electrolyte with the firmly-anchored trace H2O, while avoiding the direct contact between the reactive electrode and movement-restricted H2O. Using this modification, the lithium metal anode exhibits outstanding cyclic stability, and the high-loading LiNi0.6Co0.2Mn0.2O2-coupled LMBs present excellent capacity retention (above 72% over 500 cycles). Enlightening, this scalable carrier strategy can be further developed with synergistic effects of specific additives, accelerating the commercialization of sustainable, affordable, and secure LMBs.