Influence of sintering additives on Li + conductivity and electrochemical property of perovskite-type Li 3/8 Sr 7/16 Hf 1/4 Ta 3/4 O 3

Solid-State Electrolytes and Electrode/Electrolyte Interfaces in Rechargeable Batteries

Solid-state batteries (SSBs) are considered to be one of the most promising candidates for next-generation energy storage systems due to the high safety, high energy density and wide operating temperature range of solid-state electrolytes (SSEs) they use. Unfortunately, the practical application of SSEs has rarely been successful, which is largely attributed to the low chemical stability and ionic conductivity, ineluctable solid-solid interface issues including limited ion transport channels, high energy barriers, and poor interface contact. A comprehensive understanding of ion transport mechanisms of various SSEs, interactions between fillers and polymer matrixes and the role of the interface in SSBs are indispensable for rational design and performance optimization of novel electrolytes. The categories, research advances and ion transport mechanism of inorganic glass/ceramic electrolytes, polymer-based electrolytes and corresponding composite electrolytes are detailly summarized and discussed. Moreover, interface contact and compatibility between electrolyte and cathode/anode are also briefly discussed. Furthermore, the electrochemical characterization methods of SSEs used in different types of SSBs are also introduced. On this basis, the principles and prospects of novel SSEs and interface design are curtly proposed according to the development requirements of SSBs. Moreover, the advanced characterizations for real-time monitoring of interface changes are also brought forward to promote the development of SSBs.

A cost-effective and humidity-tolerant chloride solid electrolyte for lithium batteries

Li-ion-conducting chloride solid electrolytes receive considerable attention due to their physicochemical characteristics such as high ionic conductivity, deformability and oxidative stability. However, the raw materials are expensive, and large-scale use of this class of inorganic superionic conductors seems unlikely. Here, a cost-effective chloride solid electrolyte, Li₂ZrCl₆, is reported. Its raw materials are several orders of magnitude cheaper than those for the state-of-the-art chloride solid electrolytes, but high ionic conductivity (0.81 mS cm^–1 at room temperature), deformability, and compatibility with 4V-class cathodes are still simultaneously achieved in Li₂ZrCl₆. Moreover, Li₂ZrCl₆ demonstrates a humidity tolerance with no sign of moisture uptake or conductivity degradation after exposure to an atmosphere with 5% relative humidity. By combining Li₂ZrCl₆ with the Li-In anode and the single-crystal LiNi_0.8Mn_0.1Co_0.1O₂ cathode, we report a room-temperature all-solid-state cell with a stable specific capacity of about 150 mAh g^–1 for 200 cycles at 200 mA g^–1.

Stable inorganic solid electrolytes are instrumental in developing high-voltage Li metal batteries. Here, the authors present the synthesis and electrochemical energy storage properties of a cost-effective and humidity-tolerant chloride solid electrolyte.