US-12627017-B2 - Secondary battery

US12627017B2US 12627017 B2US12627017 B2US 12627017B2US-12627017-B2

Abstract

A secondary battery disclosed herein includes an electrode body, a case body having an opening that houses the electrode body, and a lid mounted at the opening of the case body. The lid includes a liquid injection port through which an electrolyte is injected, an insulation member mounted on an inner surface of the lid, and an insulation holder that is mounted on the insulation member and at least a portion of which is opposed to the liquid injection port at an interval. The insulation holder includes a liquid receiving portion disposed in a position opposed to the liquid injection port, and an electrode body protective portion disposed in a position closer to the electrode body than a position of the liquid receiving portion.

Inventors

Kazuki Oshima
Yoshinori Yokoyama

Assignees

Prime Planet Energy & Solutions, Inc.

Dates

Publication Date: 20260512
Application Date: 20221220
Priority Date: 20211221

Claims (8)

1 . A secondary battery comprising: an electrode body; a case body having an opening that houses the electrode body; and a lid mounted at the opening of the case body, wherein the lid includes a liquid injection port through which an electrolyte is injected, an insulation member mounted on an inner surface of the lid, and an insulation holder that is mounted on the insulation member and at least a portion of which is opposed to the liquid injection port at an interval, and the insulation holder includes a liquid receiving portion disposed in a position opposed to the liquid injection port such that electrolyte injected through the liquid injection port hits the liquid receiving portion, an electrode body protective portion disposed in a position closer to the electrode body than a position of the liquid receiving portion, and a stepped portion disposed between the electrode body protective portion and the lid, and the liquid receiving portion being provided in the stepped portion.
2 . The secondary battery according to claim 1 , wherein the electrode body protective portion is formed in a flat plate-like shape.
3 . The secondary battery according to claim 1 , wherein the insulation holder has a hole through which the electrolyte is injected from the liquid injection port in a position shifted from the liquid injection port.
4 . The secondary battery according to claim 1 , wherein the insulation holder includes a support portion extending from the electrode body protective portion toward the lid.
5 . The secondary battery according to claim 1 , wherein a partition portion that partitions a tab extends from the liquid receiving portion toward the electrode body.
6 . The secondary battery according to claim 1 , further comprising a current collecting terminal mounted on the lid, wherein in the electrode body, a positive electrode sheet, a negative electrode sheet, and a separator are stacked, at least one of the positive electrode sheet and the negative electrode sheet includes a plurality of current collecting tabs connected to the current collecting terminal so as to extend around the stepped portion from different directions, and the stepped portion includes a partition portion provided to extend from the liquid receiving portion toward the electrode body to separate the plurality of current collecting tabs that extend around the stepped portion from different directions.
7 . The secondary battery according to claim 1 , wherein the insulation member includes a first claw and a first fitting portion, the insulation holder includes a second claw and a second fitting portion, the first claw is fitted to the second fitting portion, and the second claw is fitted to the first fitting portion.
8 . The secondary battery according to claim 1 , wherein the electrode body protective portion is provided as a pair of members located on either side of the stepped portion.

Description

CROSS REFERENCE OF RELATED APPLICATION The present application claims priority from Japanese Patent Application No. 2021-207390 filed on Dec. 21, 2021, which is incorporated by reference herein in its entirety. BACKGROUND The present disclosure relates to a secondary battery. Japanese Laid-open Patent Publication No. 2019-129129 discloses a storage device including an electrode body including a first electrode plate, a second electrode plate, and a separator disposed between the first electrode plate and the second electrode plate, an exterior body that houses the electrode body, a lid that closes an opening of the exterior body, and an electrode terminal that is electrically connected to the electrode body and has a portion exposed to outside of the exterior body through the lid. The lid of the storage device disclosed in Japanese Laid-open Patent Publication No. 2019-129129 has a liquid injection hole through which an electrolyte is injected into the exterior body. In the lid, a cylindrical boy disposed between an outer surface of the lid and the electrode body and extending from the lid toward the electrode body to surround an opening of the liquid injection hole in a surface of the lid located closer to the electrode body is provided. A shielding portion provided between the liquid injection hole and the electrode body is connected to the cylindrical body, According to a configuration described above, in supplying an electrolyte into the exterior body through the liquid injection hole, a flow rate of the electrolyte when the electrolyte hits the electrode body in the exterior body can be reduced by the shielding portion. Therefore, occurrence of damage, peeling, and slipping of a material of the electrode body can be suppressed. SUMMARY Incidentally, the present inventors desire to suppress damage of an electrode body housed in a battery case. A secondary battery disclosed herein includes an electrode body, a case body having an opening that houses the electrode body, and a lid mounted at the opening of the case body. The lid includes a liquid injection port through which an electrolyte is injected, an insulation member mounted on an inner surface of the lid, and an insulation holder that is mounted on the insulation member and at least a portion of which is opposed to the liquid injection port at an interval. The insulation holder includes a liquid receiving portion disposed in a position opposed to the liquid injection port, and an electrode body protective portion disposed in a position closer to the electrode body than a position of the liquid receiving portion. According to a configuration described above, a momentum of the electrolyte in injecting the electrolyte is weakened, so that damage of the electrode body is prevented. The electrode body protective portion may be formed in a flat plate-like shape. The insulation holder may have a hole through which the electrolyte injected from the liquid injection port in a position shifted from the liquid injection port. The insulation holder may include a support portion extending from the electrode body protective portion toward the lid. A partition portion that partitions a tab may extend from the liquid receiving portion toward the electrode body. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a secondary battery. FIG. 2 is a cross-sectional view taken along a line II-II of FIG. 1. FIG. 3 is a cross-sectional view taken along a line II-III of FIG. 1. FIG. 4 is a perspective view of an insulation member. FIG. 5 is a perspective view of an insulation holder. FIG. 6 is a cross-sectional view of a secondary battery according to another embodiment. DETAILED DESCRIPTION One embodiment of a secondary battery disclosed herein will be described below. As a matter of course, the embodiments described herein is not intended to be particularly limiting the present disclosure. The accompanying drawings are schematic and do not necessarily reflect actual members or portions. Note that, in the following drawings, members/portions that have the same effect may be denoted by the same sign and the overlapping description may be omitted or simplified. As used herein, a term “secondary battery” refers to overall storage devices in which charge carriers move between a pair of electrodes (a positive electrode and a negative electrode) via an electrolyte and thus a charging and discharging reaction occurs. Such secondary batteries include not only so-called storage batteries, such as a lithium-ion secondary battery, a nickel hydrogen battery, a nickel cadmium battery, or the like, but also capacitors, such as an electric double-layered capacitor or the like. Embodiments in which a lithium-ion secondary battery, among the above-described secondary batteries, is a target will be described below. <Secondary Battery 10> FIG. 1 is a perspective view of a secondary battery 10. FIG. 2 is a cross-sectional view taken along a line II-II of FIG. 1. FIG. 2 schematic