Solid electrolyte materials for lithium-ion batteries

Abstract

The invention provides a solid-state electrolyte material of a lithium ion battery. The general formula of the solid-state electrolyte material is (LimZn)MP2X12, and the solid-state electrolyte belongs to a triclinic crystal system and a P1 space group, wherein Z is a high-valence metal element, the cationic valence is more than +1 valence and less than or equal to +3 valence, and the high-valence metal element Z is at least one of Mg, Al, Ca, Ti, Cu, Zn, Ga, In, Sr, Ru, Rh, Pd, Ag, Cd, Ba, Os, Ir, Pt or Hg; M is at least one of Ge, Si, Sn, Al or P; and X is at least one of O, S or Se. The research on the micro structure characteristics of the solid-state electrolyte material (LimZn)MP2X12 indicates that the micro interaction mechanisms such as Coulomb force, Van der Waals force and the like have important effect on the structure stability of the solid electrolyte material; and by enhancing the Coulomb attraction effect among ions and enhancing the shielding of the Coulomb repulsion effect among the ions, the total energy of the material system is greatly reduced, thereby enhancing the structure stability of the solid electrolyte material.

Description

technical field [0001] The invention relates to the field of lithium ion batteries, in particular to a solid electrolyte material for lithium ion batteries. Background technique [0002] The application of solid-state electrolytes in lithium-ion batteries instead of traditional liquid organic electrolytes can greatly improve the safety performance of traditional lithium-ion batteries, so solid-state electrolytes have long attracted attention. From the 1970s to the present, the development of solid-state electrolytes has gone through three stages: the first stage was from the 1970s to the 1990s, and the focus of research during this period was polymer electrolytes, whose ionic conductivity at room temperature was about 10 -5 S / cm, much lower than the ionic conductivity of traditional liquid organic electrolytes (approximately 10 -3 S / cm); the second stage was the 20 years after the 1990s, during which the solid electrolyte materials studied were mainly perovskite oxide mate...

AI Technical Summary

Problems solved by technology

Although the Ceder group has done a series of simulation studies on the structure of LGPS materials and verified the rapid diffusion of lithium ions in LGPS materials, they have not studied the microcosmic interaction mechanism between atoms in LGPS materials clearly, so they cannot get from the root cause Finding the key factor that enhances its structural stability

[0007] On the other hand, there are still many problems in the application of LGPS materials in all-solid-state lithium-ion batteries. One of them is that it is prone to decomposition at the interface with electrode materials, which affects the electrochemical performance of LGPS materials. The main reason is the easy decomposition of the structure of the LGPS material itself

Therefore, it is of great significance to directly find a solution to enhance the structural stability of LGPS materials experimentally, but it is difficult, costly and long-term

Images