KR-20260063158-A - Anode active material, method for preparing the same, and rechargeable lithium battery comprising the same

KR20260063158AKR 20260063158 AKR20260063158 AKR 20260063158AKR-20260063158-A

Abstract

The present invention relates to a negative electrode active material having improved lifespan and output characteristics due to enhanced binding strength by including at least one metal-containing particle and a conductive polymer, a method for manufacturing the same, and a lithium secondary battery including the same.

Inventors

이종하
권세만
강성환
장보옥
최영화
김태완
문지완

Assignees

주식회사 한솔케미칼

Dates

Publication Date: 20260507
Application Date: 20241030

Claims (15)

Comprising at least one metal-containing particle and a conductive polymer, Cathode active material.
In paragraph 1, The metal-containing particles are coated with the conductive polymer, either wholly or partially on the surface. Cathode active material.
In paragraph 1, The above metal-containing particles comprise one or more selected from the group consisting of Si, Al, Sn, Ge, Pb, In, As, Sb, P, and Ag. Cathode active material.
In paragraph 1, Based on 100% by weight of the total weight of the negative electrode active material, The content of the conductive polymer is 0.1 wt% or more and 6.5 wt% or less, Cathode active material.
In paragraph 1, The conductive polymer is a poly(3,4-ethylenedioxythiophene) (PEDOT) homopolymer or copolymer, a polyphenylene sulfide (PPS) homopolymer or copolymer, a polyaniline (PANI) homopolymer or copolymer, a polypyrrole (PPY) homopolymer or copolymer, a polyacetone (PAC) homopolymer or copolymer, a polyphenylene vinylene (PPV) homopolymer or copolymer, or a combination thereof. Cathode active material.
In paragraph 1, The conductive polymer is a copolymer of the poly(3,4-ethylenedioxythiophene), PEDOT, and the polyphenylene sulfide (PPS). Cathode active material.
In paragraph 1, The pH of the above conductive polymer is 2 or higher and 5 or lower, and Viscosity of 10 cP or more and 300 cP or less, Cathode active material.
In paragraph 1, electrical conductivity of 3 S/cm or higher, Cathode active material.
In paragraph 1, Amorphous carbon, crystalline carbon, or a combination thereof additionally comprising, Cathode active material.
In paragraph 1, The above metal-containing particles are silicon (Si)-containing particles, Cathode active material.
In paragraph 1, The average particle size (D50) of the metal-containing particles is 60 nm or more and 160 nm or less, Cathode active material.
A method for manufacturing a negative electrode active material according to any one of claims 1 to 11, A step of preparing a precursor powder by spray-drying a solution containing metal-containing particles; A step of introducing a conductive polymer into the above precursor powder; and Includes a heat treatment step; The above metal comprises one or more selected from the group consisting of Si, Al, Sn, Ge, Pb, In, As, Sb, P, and Ag. Method for manufacturing a negative electrode active material.
In Paragraph 12, In the step of adding the conductive polymer to the above precursor powder, the content of the conductive polymer added is 0.1% by weight or more and 6.5% by weight or less, based on 100% by weight of the total weight of the negative electrode active material. Method for manufacturing a negative electrode active material.
A cathode active material comprising any one of claims 1 to 11, electrode.
A cathode comprising a cathode active material according to any one of claims 1 to 11; An anode positioned opposite to the above cathode; and an electrolyte disposed between the above-mentioned cathode and the above-mentioned anode; comprising Lithium secondary battery.

Description

Anode active material, method for preparing the same, and rechargeable lithium battery comprising the same The present invention relates to a negative electrode active material, a method for manufacturing the same, and a lithium secondary battery including the same. Specifically, the invention relates to a negative electrode active material comprising at least one metal-containing particle and a conductive polymer, wherein lifespan characteristics and output characteristics are improved due to enhanced binding strength, a method for manufacturing the same, and a lithium secondary battery including the same. Lithium-ion batteries (LIBs) possess high energy density and are easy to design, so they are widely adopted as the primary power source for mobile electronic devices, and their application range is expanding further in the future to include electric vehicles and power storage devices for new and renewable energy. In order to apply them to new fields, continuous research is required on LIB materials with characteristics such as higher energy density and longer lifespan. In particular, regarding cathode materials, research has been conducted on various materials including carbon, silicon, tin, and germanium. Among these, silicon-based anode materials have attracted significant attention due to their very high energy density compared to currently commercialized graphite anode materials. However, silicon-based cathode materials have fatal drawbacks, such as the deterioration of electrochemical properties due to the formation of an unstable SEI layer caused by side reactions between the silicon surface and the electrolyte, or the pulverization of the electrode material due to internal stress resulting from rapid volume expansion during charging and discharging. To address this, much research has been conducted to improve battery characteristics through various surface treatments of silicon-based cathode materials, and in particular, methods of surface coating or composite with carbon materials are being widely studied. However, there are still limitations to improving battery lifespan, and there is a need for technological development regarding surface treatment of silicon-based anode active materials that suppresses volume expansion while simultaneously improving battery lifespan. FIG. 1 is a schematic diagram showing a negative electrode active material according to one embodiment of the present invention. Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Therefore, it should be understood that the configuration of the embodiments described in this specification is merely one of the most preferred embodiments of the present invention and does not represent all of the technical ideas of the present invention, and that various equivalents and modifications that can replace them may exist at the time of filing this application. In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “comprising,” or “having” are intended to specify the existence of the implemented features, numbers, steps, components, or combinations thereof, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, components, or combinations thereof. In the present specification, "a to b" and "a~b" indicating numerical ranges, "to" and "~" are defined as ≥ a and ≤ b. A negative electrode active material according to one aspect of the present invention may include at least one metal-containing particle and a conductive polymer, as shown in FIG. 1. In one embodiment, the surface of the metal-containing particles may be coated with the conductive polymer, either wholly or partially. At this time, as the conductive polymer coats the surface of the metal-containing particles entirely or partially, the binding strength of the negative electrode active material can be enhanced due to the binding properties of the conductive polymer. In particular, by selectively strengthening the binding force of the negative electrode active material with large volume expansion, stable expansion and contraction of the electrode plate are enabled even during repeated charging and discharging, thereby improving the battery's lifespan characteristics (capacity retention rate). In addition, due to the high electrical conductivity of the conductive polymer, electrical connections between particles are maintained, which can also improve the output characteristics of the battery. In one embodiment, as the conductive polymer coats the surface of the metal-containing particles in whole or in