Search

The integrated approach of interfacial engineering and composite electrolytes is crucial for the market application of Li metal batteries (LMBs). A 22 μm thin-film type polymer/Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) composite solid-state electrolyte (LPCE) was designed that combines fast ion conduction and stable interfacial evolution, enhancing lithium metal interface stability and cycling performance. The ether-based molecular coordination groups/clusters formed by triethylene glycol dimethyl ether (TGDE) and anions facilitated the movement of Li + between the polymer chain segments. These specific coordination clusters significantly "constrained" the interaction between anions and Li + , inducing the anions to follow the clusters to the Li metal and preferentially participate in solid electrolyte interface (SEI) derivatization. The inorganic salt-rich gradient SEI modulates Li + deposition and inhibits uncontrolled dendrite growth, achieving stable cycling of Li symmetric cell at 0.2 mA cm -2 for over 2000 h. Furthermore, the Li||NCM811 cell at a rate of 0.1 C exhibits an initial discharge capacity of 194.5 mAh g -1 , maintaining a capacity retention rate of over 90% after 500 cycles. This work demonstrates the importance of domain-limited ion clusters in ion transport and interfacial evolution, providing a perspective for solid-state LMBs.

Solid-state Li metal batteries (SSLMBs) are widely investigated since they possess promising energy density and high safety. However, the poor interfacial compatibility between the electrolyte and electrodes limits their promising development. Herein, a robust composite electrolyte (poly(vinyl ethylene carbonate) electrolyte with 3 wt % of BaTiO 3 , PVEC-3BTO) with excellent interfacial performance is rationally designed by incorporating ferroelectric BaTiO 3 (BTO) nanoparticles into the poly(vinyl ethylene carbonate) (PVEC) electrolyte matrix. Benefiting from the high dielectric constant and ferroelectric properties of BTO, the interfacial compatibility between electrolytes and electrodes was significantly improved. The enhanced Li + transference number (0.64) of solid electrolyte and in situ generated BaF 2 inorganic interphase contribute to the enhanced cycling stability of PVEC-3BTO based Li//Li symmetrical batteries. Furthermore, the antioxidation ability of PVEC-3BTO has also been enhanced by modulating the local electric field for good pairing with high-voltage LiCoO 2 material. Therefore, in this work, the mechanism of BTO for improving interfacial compatibility is revealed, and also useful methods for addressing the interface issues of SSLMBs have been provided.