Electrode assembly, battery, and battery pack and vehicle including the same

Patent metadata

Field	Value
Publication number	US-12249681-B2
Application number	US-202218294117-A
Country	US
Kind code	B2
Filing date	Jul 19, 2022
Priority date	Nov 19, 2021
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

An electrode assembly, a battery, and a battery pack and a vehicle including the same are provided. One end of the electrode assembly includes a plurality of segment alignments in which the plurality of segment groups are aligned along a radial direction, and an electrolyte impregnation portion provided between segment alignments adjacent in a circumferential direction, wherein an end of the first active material portion is exposed between winding turns of the separator. The segments included in the segment alignment are bent toward the core to form a bending surface region. An end of the separator is spaced apart from a criterion line extending in a winding axis direction along a location corresponding to the plurality of cut grooves by 30% or less of a minimum height of the segments forming the bending surface region.

First claim

What is claimed is:

1. An electrode assembly, comprising:
a first electrode,
a second electrode, and
a separator interposed therebetween are wound around a winding axis in a winding direction to define a core and an outer circumference of the electrode assembly,
wherein the first electrode includes a first active material portion coated with an active material layer and a first uncoated portion not coated with an active material layer along the winding direction,
wherein the first uncoated portion includes a segment region divided into a plurality of independently bendable segments by a plurality of cut grooves provided along the winding direction,
wherein the segment region includes a plurality of segment groups arranged with a group separation interval along the winding direction,
wherein one end of the electrode assembly includes a plurality of segment alignments in which the plurality of segment groups are aligned along a radial direction of the electrode assembly, and an electrolyte impregnation portion provided between adjacent segment alignments in a circumferential direction of the electrode assembly,
wherein an end of the first active material portion is exposed between winding turns of the separator,
wherein the segments included in each segment alignment are bent toward the core to form a bending surface region,
wherein an end of the separator is spaced apart from a criterion line extending in the winding direction along a location corresponding to the plurality of cut grooves by a preset distance or less, and wherein the preset distance is 30% of a minimum height of the segments forming the bending surface region.

2. The electrode assembly according to claim 1 , wherein widths of the segment groups in the winding direction, arranged in the bending surface region, increase stepwise or gradually from the core toward the outer circumference.

3. The electrode assembly according to claim 1 , wherein the number of segments included in each segment group arranged in the bending surface region increases gradually or stepwise from the core to the outer circumference, and
wherein the segments included in a same segment group are identical in terms of at least one selected from a width in the winding direction, a height along the winding axis, a lower internal angle, and a separation pitch in the winding direction.

4. The electrode assembly according to claim 1 , wherein the segments included in a segment group located at a first winding turn is smaller than the segments included in a segment group located outward from the first winding turn in terms of at least one selected from a width in the winding direction, a height along the winding axis, a lower internal angle, and a separation pitch in the winding direction.

5. The electrode assembly according to claim 1 , wherein the bending surface region has a fan, rectangular, trapezoidal or parallelogram shape.

6. The electrode assembly according to claim 1 , wherein, when a line connecting a center of the core and a geometric center of a figure approximately corresponding to the bending surface region is defined as an angle measurement line, an angle between angle measurement lines of adjacent bending surface regions in the circumferential direction is substantially identical.

7. The electrode assembly according to claim 1 , wherein at least a part of the segment groups included in each segment alignment are rotated in a clockwise or counterclockwise direction based on the winding axis as the radius of the winding turn increases.

8. The electrode assembly according to claim 1 , wherein each segment alignment includes a height variable region in which heights of the segments increase stepwise from a first height (h 1 ) to an N-1 th height (h N-1 ), where N is a natural number of 3 or more, from the core of the electrode assembly toward the outer circumference of the electrode assembly, and a height uniform region in which heights of the segments are kept uniform as an N th height (h N , greater than h N-1 ).

9. The electrode assembly according to claim 8 , wherein, when a starting radius of a winding turn containing a segment with a height h k (k is a natural number of 1 to N) is defined as r k , 90% or more of a diameter of the core of the electrode assembly is not covered by the bent portion of the segment located at the r k .

10. The electrode assembly according to claim 1 , wherein, based on a cross section along the winding axis, sequentially along the radial direction, each segment alignment includes a segment skip region having no segment, a height variable region where heights of the segments vary, and a height uniform region where heights of the segments are uniform, and the plurality of segments are disposed in the height variable region and the height uniform region.

11. The electrode assembly according to claim 10 , wherein, when a number of segments meeting an imaginary line parallel to the winding axis at an arbitrary radius location of the bending surface region based on a center of the core of the electrode assembly is defined as a stack number of the segments at the corresponding radius location, the bending surface region includes a stack number uniform region where the stack number of the segments is uniform from the core toward the outer circumference and a stack number decreasing region located at an outer side of the stack number uniform region in which the stack number of the segments decreases toward the outer circumference.

12. A battery, comprising:
an electrode assembly in which a first electrode, a second electrode, and a separator interposed therebetween are wound around a winding axis in a winding direction to define a core and an outer circumference of the electrode assembly, the first electrode including a first active material portion coated with an active material layer and a first uncoated portion not coated with an active material layer along the winding direction, the first uncoated portion including a segment region divided into a plurality of independently bendable segments by a plurality of cut grooves provided along the winding direction, the segment region including a plurality of segment groups arranged with a group separation interval along the winding direction, one end of the electrode assembly including a plurality of segment alignments in which the plurality of segment groups are aligned along a radial direction of the electrode assembly, an electrolyte impregnation portion being provided between adjacent segment alignments in a circumferential direction of the electrode assembly, an end of the first active material portion being exposed between winding turns of the separator, the segments included in each segment alignment being bent toward the core to form a bending surface region, an end of the separator being spaced apart from a criterion line extending along the winding direction along a location corresponding to the plurality of cut grooves by a preset distance or less, and the preset distance being 30% of a minimum height of the segments forming the bending surface region;
a battery housing configured to accommodate the electrode assembly and electrically connected to one of the first electrode and the second electrode to have a first polarity;
a sealing body configured to seal an open end of the battery housing; and
a terminal having a surface exposed to outside the battery housing and electrically connected to another of the first electrode and the second electrode to have a second polarity.

13. The battery according to claim 12 , further comprising a current collector electrically connected to an uncoated portion of the second electrode having the

Assignees

• Lg Energy Solution Ltd

Inventors

• Park Jong-Sik
• Lim Jae-Won
• Choe Yu-Sung
• Kim Hak-Kyun
• Lee Je-Jun
• Ryu Duk-Hyun
• Lee Kwan-Hee
• Lee Byoung-Gu
• Lee Jae-Eun

Classifications

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M10/0409

  for cells with wound electrodes · CPC title

• H01M10/0587 Primary

  of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• H01M50/538

  Connection of several leads or tabs of wound or folded electrode stacks · CPC title