Positive electrode material of lithium-sulfur battery, preparation method of positive electrode material and lithium-sulfur battery

Abstract

The invention discloses a positive electrode material of a lithium-sulfur battery. The positive electrode material comprises a sulfur-containing positive electrode material and a transition metal compound. The transition metal compound can generate a transition metal sulfide when the lithium-sulfur battery performs discharging, and the transition metal sulfide is poorly soluble in an electrolyte.According to the positive electrode material, the transition metal compound and the polysulfide ions in a discharge product can form the transition metal sulfide in the lithium-sulfur battery system.The transition metal sulfide is insoluble in an electrolyte so that the transition metal sulfide plays a role in fixing the polysulfide ions of the positive electrode, and shuttling of the polysulfideis blocked fundamentally.

Description

technical field

[0001] The invention belongs to the field of chemical power sources, and in particular relates to a positive electrode material of a lithium-sulfur battery, a preparation method thereof and a lithium-sulfur battery containing the positive electrode material. Background technique

[0002] The theoretical capacity and specific energy of lithium-sulfur batteries reach 1675mAh / g and 2600Wh / kg, which are much higher than the energy density (<300wAh / kg) of iron-lithium or ternary batteries widely used in commerce, and elemental sulfur is abundant in the earth , has the characteristics of low price and environmental friendliness. Therefore, lithium-sulfur batteries are widely considered to be the development direction of next-generation high-energy-density batteries, and they are also a research hotspot for high-energy-density batteries.

[0003] However, elemental sulfur reacts with lithium ions during the electrochemical reaction to form lithium polysulfide (L...

Images