Electrode assembly including bi-cell and full-cell and secondary battery including the same

• US 10,454,132 B2
• Filed: 10/22/2015
• Issued: 10/22/2019
• Est. Priority Date: 10/31/2014
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Choi, Hyoungsik, Ryu, Sang Baek, Park, Chan Ki
• Primary Examiner(s): Mohaddes, Ladan
• Application Number:
  US15/505,512
• Publication Number:
  US 20170207481A1
• Time in Patent Office: 1,461 Days
• CPC Class Codes: H01M 10/0418 with bipolar electrodes
• CPC Class Codes: H01M 10/044 with bipolar electrodes
• CPC Class Codes: H01M 10/0459 Cells or batteries with folded separator between plate-like electrodes
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0583 of accumulators with folded construction elements except wound ones, i.e. folded positive or negative electrodes or separators, e.g. with "Z"-shaped electrodes or separators
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 10/12 Construction or manufacture
• CPC Class Codes: H01M 10/28 Construction or manufacture
• CPC Class Codes: H01M 10/38 Construction or manufacture
• CPC Class Codes: H01M 50/103 prismatic or rectangular H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/107 having curved cross-section, e.g. round or elliptic H01M50/103, H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/124 having a layered structure
• CPC Class Codes: H01M 50/40 Separators; Membranes; Diaphragms; Spacing elements inside cells
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

Disclosed herein is a stacked/folded type electrode assembly configured to have a structure in which a plurality of unit cells, each of which includes a positive electrode having an electrode mixture including an electrode active material applied to a current collector, a negative electrode having an electrode mixture including an electrode active material applied to a current collector, and a separator disposed between the positive electrode and the negative electrode, is wound in the state of being arranged on a sheet type separation film, wherein the unit cells include one full cell and three or more bi-cells, the outermost unit cells of the electrode assembly are each configured such that an electrode forming the outside of the electrode assembly is configured as a single-sided electrode, in which no electrode mixture is applied to the surface of the current collector facing the outside of the electrode assembly, and the single-sided electrodes are electrodes having the same polarity.

Claims

1. An electrode assembly configured to have a structure in which a plurality of unit cells, each of which comprises a positive electrode having an electrode mixture comprising an electrode active material applied to a current collector, a negative electrode having an electrode mixture comprising an electrode active material applied to a current collector, and a separator disposed between the positive electrode and the negative electrode, is wound in a state of being arranged on a sheet type separation film, wherein

the unit cells comprise one full cell and three or more bi-cells,

outermost unit cells of the electrode assembly are each configured such that an electrode forming an outside of the electrode assembly is configured as a single-sided electrode, in which no electrode mixture is applied to a surface of the current collector facing the outside of the electrode assembly,

the single-sided electrodes are electrodes having the same polarity, and

the unit cells are wound in a state in which the unit cells are sequentially arranged in a plane from a first unit cell, which is located at a winding start point of the separation film, to a 2n-th unit cell (where n is an integer that satisfies 2≤

n≤

20), which is located at a winding end point of the separation film, and

the three or more bi-cells configured as an A-type bi-cell or a C-type bi-cell are alternatingly stacked, and the one full cell is disposed as one of the outermost unit cells.

2. The electrode assembly according to claim 1, wherein the full cell is a first full cell, which is configured to have a structure in which a first positive electrode, configured as a single-sided positive electrode, a separator, and a negative electrode are sequentially stacked, or a second full cell, which is configured to have a structure in which a first negative electrode, configured as a single-sided negative electrode, a separator, and a positive electrode are sequentially stacked, the first positive electrode or the first negative electrode facing the separation film.

3. The electrode assembly according to claim 1, wherein the A-type bi-cell, which is configured to have a structure in which a positive electrode, a negative electrode, and another positive electrode are sequentially stacked in a state in which separators are disposed therebetween, a and the C-type bi-cell, which is configured to have a structure in which a negative electrode, a positive electrode, and another negative electrode are sequentially stacked in a state in which separators are disposed therebetween.

4. The electrode assembly according to claim 3, wherein the A-type bi-cell comprises a 1A-type bi-cell, which is configured to have a structure in which a first positive electrode, configured as a single-sided positive electrode, a negative electrode, and a positive electrode are sequentially stacked in a state in which separators are disposed therebetween, or a 2A-type bi-cell, which is configured to have a structure in which a positive electrode, a negative electrode, and another positive electrode are sequentially stacked in a state in which separators are disposed therebetween.

5. The electrode assembly according to claim 3, wherein the C-type bi-cell comprises a 1C-type bi-cell, which is configured to have a structure in which a first negative electrode, configured as a single-sided negative electrode, a positive electrode, and a negative electrode are sequentially stacked in a state in which separators are disposed therebetween, or a 2C-type bi-cell, which is configured to have a structure in which a negative electrode, a positive electrode, and another negative electrode are sequentially stacked in a state in which separators are disposed therebetween.

6. The electrode assembly according to any one of claims 2 to 5, wherein the first unit cell is a bi-cell, the 2n-th unit cell is a 1A-type bi-cell, and a (2n−

1)-th unit cell is a first full cell.

7. The electrode assembly according to any one of claims 2 to 5, wherein the first unit cell is a bi-cell, the 2n-th unit cell is a 1C-type bi-cell, and a (2n−

1)-th unit cell is a second full cell.

8. The electrode assembly according to any one of claims 2 to 5, wherein the first unit cell is a bi-cell, the 2n-th unit cell is a first full cell, and a (2n−

1)-th unit cell is a 1A-type bi-cell.

9. The electrode assembly according to any one of claims 2 to 5, wherein the first unit cell is a bi-cell, the 2n-th unit cell is a second full cell, and a (2n−

1)-th unit cell is a 1C-type bi-cell.

10. The electrode assembly according to claim 1, wherein the single-sided electrode is a first positive electrode.

11. The electrode assembly according to claim 1, wherein the single-sided electrode is a first negative electrode.

12. A secondary battery comprising an electrode assembly according to claim 1 mounted in a battery case.

13. The secondary battery according to claim 12, wherein the battery case is a pouch-shaped case made of an aluminum laminate sheet or a can-shaped case.

14. A battery pack comprising a secondary battery according to claim 13 as a unit cell.

15. A device comprising a battery pack according to claim 14 as a power source.

16. The device according to claim 15, wherein the device is a mobile electronic device, a power tool driven by a battery-powered motor, an electric automobile, such as such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV), an electric two-wheeled vehicle, such as an electric bicycle (E-bike) or an electric scooter (E-scooter), an electric golf cart, or a power storage system.