US 12,246,602 B2
Secondary battery, battery pack, electronic device, electric tool, electric aircraft, and electric vehicle
Yusuke Muroi, Kyoto (JP)
Assigned to Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed by MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed on Feb. 2, 2022, as Appl. No. 17/591,271.
Application 17/591,271 is a continuation of application No. PCT/JP2020/029444, filed on Jul. 31, 2020.
Claims priority of application No. 2019-144677 (JP), filed on Aug. 6, 2019.
Prior Publication US 2022/0153147 A1, May 19, 2022
Int. Cl. B60L 50/64 (2019.01); B64C 27/32 (2006.01); B64D 27/24 (2024.01); B64U 50/30 (2023.01); H01M 10/0587 (2010.01); H01M 50/531 (2021.01)
CPC B60L 50/64 (2019.02) [B64C 27/32 (2013.01); B64D 27/24 (2013.01); B64U 50/30 (2023.01); H01M 10/0587 (2013.01); H01M 50/531 (2021.01); H01M 2220/20 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A secondary battery comprising:
an electrode wound body having a structure in which a positive electrode and a negative electrode are stacked and wound with a separator interposed therebetween;
a positive electrode current collector plate;
a negative electrode current collector plate; and
an exterior can that accommodates the electrode wound body, the positive electrode current collector plate, and the negative electrode current collector plate,
wherein the positive electrode has a first covered portion covered with a positive electrode active material layer and a positive electrode active material non-covered portion on a positive electrode foil,
the negative electrode has a second covered portion covered with a negative electrode active material layer and a negative electrode active material non-covered portion on a negative electrode foil,
the positive electrode active material non-covered portion is joined to the positive electrode current collector plate on a first end face of the electrode wound body,
the negative electrode active material non-covered portion is joined to the negative electrode current collector plate on a second end face of the electrode wound body,
one or both of the positive electrode active material non-covered portion and the negative electrode active material non-covered portion have a flat face formed by the positive or negative electrode active material non-covered portion bending and overlapping toward a central axis of the wound structure,
the flat face has at least one groove extending from an inner peripheral portion toward an outer peripheral portion of the electrode wound body when the electrode wound body has a closed profile in a radial direction of the central axis, wherein the at least one groove comprises an area where at least two adjacent outer edges of the flat face are separated, and
a width (W1) of the groove in the inner peripheral portion is smaller than a width (W2) of the groove in the outer peripheral portion, wherein the widths correspond to the area where at least two adjacent outer edges of the flat face are separated.