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KR-102961535-B1 - Current collector having negative and positive characteristics and secondary battery including the same

KR102961535B1KR 102961535 B1KR102961535 B1KR 102961535B1KR-102961535-B1

Abstract

The present invention relates to a current collector having excellent corrosion resistance and possessing both negative and positive electrode characteristics when a lithium metal negative electrode or a sulfide-based solid electrolyte is applied, and a secondary battery including the same. A current collector according to the present invention is characterized by comprising a current collector substrate made of an alloy including iron (Fe) and nickel (Ni), and an anode characteristic material layer formed on one surface of the current collector substrate.

Inventors

  • 정관호
  • 이응래
  • 유신
  • 김기수

Assignees

  • 주식회사 프렘투

Dates

Publication Date
20260507
Application Date
20230228

Claims (12)

  1. A current collector substrate comprising 10 to 33 weight% or 40 to 90 weight% nickel (Ni) and the remainder being iron (Fe) and unavoidable impurities, and It includes an anode characteristic material layer formed on one surface of the above-mentioned current collector substrate, and The above anode characteristic material layer is composed of aluminum (Al) and an alloy thereof, and A current collector having both negative and positive electrode characteristics, suitable for lithium metal batteries or sulfide-based all-solid-state batteries.
  2. In Article 1, A current collector having both negative and positive properties, further comprising a negative property material layer formed on the other side of the above current collector substrate.
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  4. In Article 1, A current collector having both negative and positive characteristics, wherein the thickness of the current collector substrate is 3.5㎛ to 20㎛.
  5. delete
  6. In Article 2, A current collector having both cathodic and anode characteristics, wherein the cathodic characteristic material layer comprises at least one selected from the group consisting of copper (Cu), nickel (Ni), titanium (Ti), chromium (Cr), molybdenum (Mo), silver (Ag), cobalt (Co), gold (Au), ruthenium (Ru), platinum (Pt), iridium (Ir), and alloys thereof.
  7. In Article 1, A current collector having both cathodic and anode characteristics, wherein the thickness of the anode characteristic material layer is 0.09 to 2 μm.
  8. In Article 2, A current collector having both cathodic and anode characteristics, wherein the thickness of the cathodic characteristic material layer is 10 nm to 1 µm.
  9. In any one of Articles 1, 2, 4, 6, 7, and 8, The above current collector is a current collector having both negative and positive characteristics, having a resistivity value of 20× 10⁻⁸ Ωm or less.
  10. In any one of Articles 1, 2, 4, 6, 7, and 8, A current collector having both negative and positive properties, wherein the average grain size of the current collector substrate is 15 nm or less (excluding 0 nm), the tensile strength of the current collector substrate is 800 MPa or more, and the elongation is 2% or more.
  11. The entire first house and, A first positive active material layer formed on the first current collector, and A first electrolyte layer formed on the first positive active material layer, and A first negative active material layer formed on the first electrolyte layer, and A second current collector formed on the first negative active material layer, and A second positive active material layer formed on the second current collector, and A second electrolyte layer formed on the second positive active material layer, and A second negative active material layer formed on the second electrolyte layer, and It includes a third current collector formed on the second negative active material layer, A secondary battery, wherein the second current collector is a current collector having all the negative and positive electrode characteristics described in any one of claims 1, 2, 4, 6, 7, and 8.
  12. In Article 11, A secondary battery comprising a first electrolyte layer and a second electrolyte layer comprising a solid electrolyte.

Description

Current collector having both negative and positive characteristics and secondary battery including the same The present invention relates to a current collector having excellent corrosion resistance and possessing both negative and positive electrode characteristics when a lithium metal negative electrode or a sulfide-based solid electrolyte is applied, and a secondary battery including the same. Lithium-ion batteries are widely commercialized due to their superior energy density and power output characteristics among various types of rechargeable batteries. Furthermore, as demand for electric vehicles and large-capacity power storage devices increases, there is a need for the development of high-energy batteries to meet these needs. Technology for applying lithium metal anodes to secondary batteries is being actively developed as a method to achieve high energy densities of over 400 Wh/kg. However, there have been recent reports that when lithium metal is applied to the anode, corrosion occurs in the copper foil used as the anode current collector, leading to a decrease in battery life. Meanwhile, carbonate-based organic solvents included in the liquid electrolytes currently widely used in lithium-ion batteries have problems such as low thermal stability and very high flammability. To address this, all-solid-state battery technology using solid electrolytes is being actively researched; however, in sulfide-based all-solid-state batteries, which are the most actively researched and developed, a problem is emerging in which sulfide-based solid electrolytes corrode the copper foil current collector. In secondary batteries, the current collector acts as a connecting medium to supply electrons or holes provided from an external wire to the electrode active material, or conversely, as a carrier that collects electrons or holes generated as a result of the electrode reaction and flows them to the external wire. In addition, the current collector functions as an important support in realizing the shape of the actual electrode plate, and it is important that the metal constituting the current collector does not oxidize in the low potential region for the negative electrode current collector and in the high potential region for the positive electrode current collector. Generally, considering electrical conductivity, electrochemical stability, and suitability for the electrode plate manufacturing process, copper (Cu) is used for the negative electrode and aluminum (Al) or platinum (Pt) is used for the positive electrode, and active material particles are coated on top of them and dried to manufacture the electrode. However, as mentioned above, copper foil (Cu foil) has the critical problem of corrosion occurring in lithium metal batteries and sulfide-based all-solid-state batteries. Furthermore, since aluminum (Al) cannot be used as a negative electrode, it is impossible to utilize aluminum alone as a current collector that possesses both negative and positive electrode characteristics. Additionally, platinum (Pt) is excessively expensive, which increases battery costs, thus presenting limitations in terms of low economic efficiency for its application and mass production in batteries. Figure 1 shows a cross-sectional structure of a current collector having both negative and positive electrode characteristics according to a first embodiment of the present invention. FIG. 2 shows a cross-sectional structure of a current collector having both negative and positive electrode characteristics according to a second embodiment of the present invention. FIG. 3 shows the cross-sectional structure of a solid electrolyte battery having both negative and positive electrode characteristics according to the third embodiment of the present invention. FIG. 4 shows the cross-sectional structure of a solid electrolyte battery having both negative and positive electrode characteristics according to the fourth embodiment of the present invention. Embodiments of the present invention are described below with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. In addition, to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals. Throughout this specification, when a part is described as being "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "electrically connected" with other elements interposed between them. Throughout the entire specification, when a component is described as being located "on," "on top," "on top," "under," "on bottom," or "on bottom" of another component, this includes not only cases where the component is in contact with the othe