Role of Interfaces in Solid‐State Batteries

Abstract

Solid‐state batteries (SSBs) are considered as one of the most promising candidates for the next‐generation energy‐storage technology, because they simultaneously exhibit high safety, high energy density, and wide operating temperature range. The replacement of liquid electrolytes with solid electrolytes produces numerous solid–solid interfaces within the SSBs. A thorough understanding on the roles of these interfaces is indispensable for the rational performance optimization. In this review, the interface issues in the SSBs, including internal buried interfaces within solid electrolytes and composite electrodes, and planar interfaces between electrodes and solid electrolyte separators or current collectors are discussed. The challenges and future directions on the investigation and optimization of these solid–solid interfaces for the production of the SSBs are also assessed.

Halide solid-state electrolytes for all-solid-state batteries: structural design, synthesis, environmental stability, interface optimization and challenges

“…96,100 However, as with other inorganic SSEs, halide electrolytes also need to overcome the interface problem with electrode materials. 20,142,143…”

Surface Li2CO3 Mediated Phosphorization Enables Compatible Interfaces of Composite Polymer Electrolyte for Solid‐State Lithium Batteries

“…Li anode) greatly constrain the electrochemical performance of solid-state lithium batteries. [16][17][18][19] LLZO is unstable in ambient air and can chemically react with CO 2 and H 2 O, resulting in the formation of a Li 2 CO 3 passivation layer. [20][21][22][23][24][25] On one hand, Li 2 CO 3 is lithium-ion insulative and lithiophobic, severely hindering fast Li + exchange at the PVDF-HFP/LLZO interfaces and thus leading to the significantly decreased ionic conductivity of CPEs and increased area-specific resistance with electrodes.…”

“…[ 12–15 ] Unfortunately, the severe (electro)chemical instabilities and incompatibility of multiple interfaces and other cell components (e.g., cathode, anode) greatly constrain the electrochemical performance of solid‐state lithium batteries. [ 16–19 ]…”

Revealing the Influence of Surface Microstructure on Li Wettability and Interfacial Ionic Transportation for Garnet‐Type Electrolytes

“…[16,17] However, the poor chemical stability of LLZO causes the formation of lithiophobic species (e.g., Li 2 CO 3 and LiOH) on its surface upon contact with water and air, [18][19][20] which compromises the electrodeelectrolyte contact and leads to high interfacial impedance (R int ) and the consequent low critical current density (CCD). [9,[21][22][23] In addition to that, the poor contact between LLZO and lithium metal will also cause inhomogeneous lithium-ion flux through the interface, triggering unfavorable dendrites growth/propagation, especially at locations such as defects and cracks. [24] Thus, interfacial engineering to improve the interfacial wettability and reduce interfacial impedance is essential for the particle application of LLZO.…”