Positive electrode material, preparation method thereof, a positive plate and lithium-sulfur battery

Abstract

The invention provides a positive electrode material of a lithium-sulfur battery, a preparation method thereof, a positive plate and the lithium-sulfur battery. The positive electrode material contains dedoped polyaniline. The preparation method of the positive electrode material includes the steps that 1, the dedoped polyaniline is prepared; 2, a dedoped polyaniline solution is prepared; the positive electrode material is prepared. The positive plate comprises a current collector and an active layer combined with the surface of the current collector, wherein the active layer contains the positive electrode material. The lithium-sulfur battery comprises the positive plate. During charging and discharging, the positive electrode material generates new electrochemical kinetics behaviors to restrain a shuttle flying effect, and the structure is simple. The positive plate comprising the positive electrode material has the advantages that the gram volume of active substances is high, the dissolve-loss rate of the active substances is low, and the structure is stable; according to the lithium-sulfur battery including the positive plate, the specific capacity is accordingly increased greatly, and the cycle life is accordingly prolonged greatly.

Description

technical field [0001] The invention belongs to the technical field of battery materials, and in particular relates to a positive electrode material, a preparation method thereof, a positive electrode sheet and a lithium-sulfur battery. Background technique [0002] Lithium-sulfur batteries refer to a new generation of lithium-ion secondary batteries that use metallic lithium as the negative electrode and elemental sulfur as the positive electrode active material. The metal lithium battery assembled with metal lithium as the negative electrode has higher energy density and working voltage. The oxidation number of sulfur element can range from -2 to +6. Assuming that the electron transfer number of each sulfur atom is 2, using Li 2 The reversible conversion between S and S, the theoretical specific capacity is 1672mAh / g, and the theoretical energy density is 2600Wh / kg calculated according to the average voltage of 2.1V. The lithium-sulfur combination is the most energy-dense...

AI Technical Summary

Problems solved by technology

In addition, since conductive polyaniline (i.e., protonic acid-doped polyaniline) is acidic, it will cause corrosion of aluminum current collectors when used as an additive.

Therefore, its technical effect is limited, and the lithium-sulfur battery designed according to this mechanism of action will inevitably affect its effect once the conductive polymer shell is partially damaged.

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