Positive electrode plate and electrochemical device containing the same

Patent metadata

Field	Value
Publication number	US-11211610-B2
Application number	US-201916426867-A
Country	US
Kind code	B2
Filing date	May 30, 2019
Priority date	Nov 16, 2018
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

The present application relates to a positive electrode plate and an electrochemical device. The positive electrode plate includes a current collector, a positive active material layer, and a binding layer disposed between the current collector and the positive active material layer, the binding layer comprising a polymer material, a conductive material, and an inorganic filler, wherein the polymer material comprises a binding layer matrix and the binding layer matrix is an oil-dispersible polymer material having a solubility in NMP at 130° C. for 5 minutes, which is 30% or less of the solubility of PVDF under the same conditions. The positive electrode plate can improve the safety performance of the electrochemical device (for example, a capacitor, a primary battery, a secondary battery, or the like) under abnormal conditions such as nailing penetration.

First claim

The invention claimed is:

1. A positive electrode plate comprising a current collector, a positive active material layer and a binding layer disposed between the current collector and the positive active material layer,
wherein the binding layer comprises a polymer material, a conductive material and an inorganic filler, wherein the inorganic filler has a specific surface area of Brunauer-Emmett-Teller of no more than 500 m 2 /g,
wherein in the binding layer, relative to the total weight of the binding layer, the polymer material is present in an amount of 50 wt % to 75 wt %, the conductive material is present in an amount of 5 wt % to 20 wt % and the inorganic filler is present in an amount of 15 wt % to 45 wt %; and
wherein the polymer material comprises a binding layer matrix and the binding layer matrix is an oil-dispersible polymer material having a solubility in N-methyl-2-pyrrolidone at 130° C. for 5 minutes, which is 30% or less of the solubility of polyvinylidene fluoride under the same conditions and the binding layer matrix is present in an amount of 20 wt % or more, relative to the total weight of the binding layer.

2. The positive electrode plate according to claim 1 , wherein the polymer material further comprises a binder.

3. The positive electrode plate according to claim 1 , wherein in the binder layer, the polymer material further comprises an optional binder and relative to the weight of the polymer material being 100 wt %,
the binding layer matrix is present in an amount of 30 wt % to 100 wt % and
the binder is present in an amount of 0 wt % to 70 wt %.

4. The positive electrode plate according to claim 1 , wherein the binding layer matrix is selected from at least one of polyacrylonitrile, polyacrylic acid, polyacrylate, polyacrylic acid-acrylate, polyacrylonitrile-acrylic acid, and polyacrylonitrile-acrylate.

5. The positive electrode plate according to claim 2 , wherein the binder is selected from at least one of polyvinylidene fluoride, polyvinylidene chloride, polyvinylidene fluoride copolymer and polyvinylidene chloride copolymer.

6. The positive electrode plate according to claim 1 , wherein the conductive material is selected from at least one of a conductive carbon-based material, a conductive metal material, and a conductive polymer material; and
wherein the conductive carbon-based material is selected from at least one of conductive carbon black, acetylene black, graphite, graphene, carbon nanotubes, and carbon nanofibers; and
wherein the conductive metal material is selected from at least one of Al powder, Ni powder, and gold powder; and
wherein the conductive polymer material is selected from at least one of conductive polythiophene, conductive polypyrrole, and conductive polyaniline.

7. The positive electrode plate according to claim 1 , wherein the inorganic filler is selected from at least one of a metal oxide, a non-metal oxide, a metal nitride, a non-metal nitride, an inorganic salt, or at least one of a conductive carbon coating coated above material, a conductive metal coating coated above material or a conductive polymer coating coated above material.

8. The positive electrode plate according to claim 1 , wherein the inorganic filler in the binding layer is at least one of magnesium oxide, aluminum oxide, titanium dioxide, zirconium oxide, silicon dioxide, silicon carbide, boron carbide, calcium carbonate, aluminum silicate, calcium silicate, potassium titanate, barium sulfate, lithium cobalt oxide, lithium nickel manganese cobalt oxide, lithium nickel manganese aluminum oxide, lithium iron phosphate, lithium vanadium phosphate, lithium cobalt phosphate, lithium manganese phosphate, lithium iron manganese phosphate, lithium iron silicate, lithium vanadium silicate, lithium cobalt silicate, lithium manganese silicate, spinel lithium manganate, spinel lithium nickel manganate, lithium titanate, or a conductive carbon coating coated above material, a conductive metal coating coated above material, or a conductive polymer coating coated above material.

9. The positive electrode plate according to claim 1 , wherein the inorganic filler has an average particle size D of 100 nm≤D≤10 μm.

10. The positive electrode plate according to claim 1 , wherein the binding layer has a thickness H of 1 μm≤H≤20 μm and the binding layer is substantially consisted of the polymer material, the conductive material and the inorganic filler.

11. An electrochemical device, comprising the positive electrode plate according to claim 1 , the electrochemical device being a capacitor, a primary battery or a secondary battery.

Assignees

• Contemporary Amperex Technology Co Ltd

Inventors

• Li Wei
• Shi Haihao
• Liu Huihui
• Jin Chao
• Xu Jianbao
• Li Shisong
• Guo Chao

Classifications

• H01M10/4235

  Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence) · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M6/50

  Methods or arrangements for servicing or maintenance, e.g. for maintaining operating temperature (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569) · CPC title

• H01M4/622

  being polymers · CPC title

• H01M4/02 Primary

  Electrodes composed of, or comprising, active material · CPC title