In Situ Construction of an Ultra‐Stable Conductive Composite Interface for High‐Voltage All‐Solid‐State Lithium Metal Batteries

Abstract

The garnet electrolyte presents poor wettability with Li metal, resulting in an extremely large interfacial impedance and drastic growth of Li dendrites. Herein, a novel ultra-stable conductive composite interface (CCI) consisting of Li y Sn alloy and Li 3 N is constructed in situ between Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) pellet and Li metal by a conversion reaction of SnN x with Li metal at 300 8C. The Li y Sn alloy as a continuous and robust bridge between LLZTO and Li metal can effectively reduce the LLZTO/Li interfacial resistance from 4468.0 W to 164.8 W. Meanwhile, the Li 3 N as a fast Li-ion channel can efficiently transfer Li ions and give their uniform distribution at the LLZTO/Li interface. Therefore, the Li/LLZTO@CCI/ Li symmetric battery stably cycles for 1200 h without short circuit, and the all-solid-state high-voltage Li/LLZTO@CCI/ LiNi 0.5 Co 0.2 Mn 0.3 O 2 battery achieves a specific capacity of 161.4 mAh g À1 at 0.25 C with a capacity retention rate of 92.6 % and coulombic efficiency of 100.0 % after 200 cycles at 25 8C.

Hierarchical Composite‐Solid‐Electrolyte with High Electrochemical Stability and Interfacial Regulation for Boosting Ultra‐Stable Lithium Batteries

“…Impeded by the notoriously interfacial issues between ISEs and electrodes, it's hard for them to give a full play to their superiorities. Much efforts have been paid to reconcile these dilemmas with the aid of fabricating polymer buffer, [13][14][15] constructing heterogeneous metal or metal-oxide/nitride layer to form Lialloy interphase, [16][17][18] incorporating carbon-matrix materials into Li metal etc., [19,20] and yielding remarkable results. Nonetheless, these solutions often require extremely expensive and sophisticated equipment along with gigantic energy consumption during the handling process, thus obstructing the large-scale treatments in industry.…”

New Cost‐Effective Halide Solid Electrolytes for All‐Solid‐State Batteries: Mechanochemically Prepared Fe3+‐Substituted Li2ZrCl6

“…[13,33,36,39] Interfacial engineering that might enable halide SEs working with Li metal anode would be an interesting future research. [8,[66][67][68][69][70] The mechanochemically prepared halide SEs, Li 2+x Zr 1−x Fe x Cl 6 , were applied for cathodes using LiCoO 2 without any protective coating layers in all-solid-state cells tested at 30 °C (Figure 4a-f). Figure 4a shows first-cycle charge-discharge voltage profiles at 0.1C (16 mA Cl showed a distinctly different feature at the beginning of first charge compared with that which employed halide SEs: the sloping voltage profile starting at ≈3.2 V (vs Li/Li + ) (indicated by an arrow) confirmed the poor electrochemical oxidation stability of sulfide SEs.…”

Electrolyte/Electrode Interfaces in All-Solid-State Lithium Batteries: A Review

“…For example, Huo et al [124] introduced a Cu 3 N interlayer into LLZO using magnetic sputtering to react with Li to form a mixed conductive layer consisting of Li 3 N and Cu, resulting in a decrease in apparent LLZO/Li interfacial resistance from 1138.5 to 83 Ω cm 2 and a critical current density of 1.2 mA cm −2 . Similarly, a Li 3 N-Zn (or Li 3 N-Sn) composite interlayer was successfully introduced between LLZO and Li through an in situ reaction between Zn(NO 3 ) 2 and Li (or SnN x and Li) [125,126]. The formation of mixed conductive layers through electrode modification is also feasible.…”