US-20260128485-A1 - BATTERY AND BATTERY MANUFACTURING METHOD

US20260128485A1US 20260128485 A1US20260128485 A1US 20260128485A1US-20260128485-A1

Abstract

A battery includes a unit cell including an electrode current collector, a first layer, a second layer, a third layer, and a counter electrode current collector. The first layer includes an electrode active material layer and a first insulating layer having an electronic insulation property. The second layer includes a solid electrolyte layer. The third layer includes a counter electrode active material layer. A first region not covered with the first layer is provided at an end portion of the main surface of the electrode current collector in the first direction. A second region not covered with the second layer in a plan view is provided at the end portion of the first layer in the first direction. A third region not covered with the third layer in the plan view is provided at an end portion of the second layer in the first direction.

Inventors

TATSUYA OSHIMA
Tsutomu Koshizuka
Kazuhiro Morioka

Assignees

PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251219
Priority Date: 20230628

Claims (17)

1 . A battery comprising: a unit cell including: an electrode current collector; a first layer disposed on a main surface of the electrode current collector; a second layer disposed on a side of the first layer opposite from the electrode current collector; a third layer disposed on a side of the second layer opposite from the first layer; and a counter electrode current collector disposed on a side of the third layer opposite from the second layer, wherein the first layer includes an electrode active material layer and a first insulating layer having an electronic insulation property, the first insulating layer being aligned with the electrode active material layer in a first direction that is a direction from a center of the main surface towards an outer edge of the main surface of the electrode current collector, the first insulating layer being disposed at an end portion of the first layer in the first direction, the second layer includes an electrolyte layer, the third layer includes a counter electrode active material layer, a first region not covered with the first layer is provided at an end portion of the main surface of the electrode current collector in the first direction, a second region not covered with the second layer in a plan view of the main surface of the electrode current collector is provided at the end portion of the first layer in the first direction, and a third region not covered with the third layer in the plan view is provided at an end portion of the second layer in the first direction.
2 . The battery according to claim 1 , wherein the unit cell includes two first layers, two second layers, two third layers, and two counter electrode current collectors, the two first layers each being the first layer, the two second layers each being the second layer, the two third layers each being the third layer, the two counter electrode current collectors each being the counter electrode current collector, the two first layers are disposed on two main surfaces of the electrode current collector, the two main surfaces including the main surface, the two second layers are disposed on sides of the two first layers opposite from the electrode current collector, the two third layers are disposed on sides of the two second layers opposite from the two first layers, the two counter electrode current collectors are disposed on sides of the two third layers opposite from the two second layers, the first region is provided at an end portion of each of the two main surfaces of the electrode current collector in the first direction, the second region is provided at an end portion of each of the two first layers in the first direction, and the third region is provided at an end portion of each of the two second layers in the first direction.
3 . The battery according to claim 1 , wherein a fourth region not covered with the counter electrode current collector in the plan view is provided at an end portion of the third layer in the first direction.
4 . The battery according to claim 3 , wherein the unit cell includes two first layers, two second layers, two third layers, and two counter electrode current collectors, the two first layers each being the first layer, the two second layers each being the second layer, the two third layers each being the third layer, the two counter electrode current collectors each being the counter electrode current collector, the two first layers are disposed on two main surfaces of the electrode current collector, the two main surfaces including the main surface, the two second layers are disposed on sides of the two first layers opposite from the electrode current collector, the two third layers are disposed on sides of the two second layers opposite from the two first layers, the two counter electrode current collectors are disposed on sides of the two third layers opposite from the two second layers, the first region is provided at an end portion of each of the two main surfaces of the electrode current collector in the first direction, the second region is provided at an end portion of each of the two first layers in the first direction, the third region is provided at an end portion of each of the two second layers in the first direction, and the fourth region is provided at an end portion of each of the two third layers in the first direction.
5 . The battery according to claim 1 , wherein the second layer further includes a second insulating layer having an electronic insulation property, the second insulating layer being aligned with the electrolyte layer in the first direction and disposed at an end portion of the second layer in the first direction.
6 . The battery according to claim 1 , wherein the third region is part of the electrolyte layer.
7 . The battery according to claim 3 , wherein the third layer further includes a third insulating layer having an electronic insulation property, the third insulating layer being aligned with the counter electrode active material layer in the first direction, the third insulating layer being disposed at an end portion of the third layer in the first direction.
8 . The battery according to claim 1 , wherein side surfaces of the electrode current collector, the first layer, the second layer, and the third layer are flush with each other at an end portion of the unit cell in a second direction that is a direction from the center towards the outer edge of the main surface of the electrode current collector, the second direction being different from the first direction.
9 . The battery according to claim 1 , wherein side surfaces of the electrode current collector, the first layer, the second layer, the third layer, and the counter electrode current collector are flush with each other at an end portion of the unit cell in a second direction that is a direction from the center towards the outer edge of the main surface of the electrode current collector, the second direction being different from the first direction.
10 . The battery according to claim 1 , wherein at least one layer selected from a group consisting of the electrode active material layer, the first insulating layer, and the electrolyte layer includes a sulfide solid electrolyte.
11 . The battery according to claim 1 , wherein at least one layer selected from a group consisting of the electrode active material layer, the first insulating layer, and the electrolyte layer includes a styrene-based elastomer.
12 . The battery according to claim 1 , wherein part of the end portion of the counter electrode current collector in the first direction protrudes in the first direction relative to the third layer in the plan view.
13 . The battery according to claim 1 , comprising: a plurality of unit cells, each of the plurality of unit cells being the unit cell, wherein the plurality of unit cells are stacked.
14 . A battery manufacturing method comprising: preparing an electrode current collector and stacking a first layer on a main surface of the electrode current collector to provide a first region not covered with the first layer at an end portion of the main surface of the electrode current collector in a first direction that is a direction from a center of the main surface towards an outer edge of the main surface of the electrode current collector; stacking a second layer on a side of the first layer opposite from the electrode current collector to provide a second region not covered with the second layer in a plan view of the main surface of the electrode current collector at an end portion of the first layer in the first direction; stacking a third layer on a side of the second layer opposite from the first layer to provide a third region not covered with the third layer in the plan view at an end portion of the second layer in the first direction; and stacking a counter electrode current collector on a side of the third layer opposite from the second layer, wherein the first layer includes an electrode active material layer and a first insulating layer having an electronic insulation property, the first insulating layer being aligned with the electrode active material layer in the first direction, the first insulating layer being disposed at an end portion of the first layer in the first direction, the second layer includes an electrolyte layer, and the third layer includes a counter electrode active material layer.
15 . The battery manufacturing method according to claim 14 , wherein in the stacking of the counter electrode current collector, the counter electrode current collector is stacked on the third layer to provide a fourth region not covered with the counter electrode current collector in the plan view at an end portion of the third layer in the first direction.
16 . The battery manufacturing method according to claim 14 , further comprising: forming a cut surface at an end portion of a stacked body in a second direction by collectively cutting the electrode current collector, the first layer, the second layer, and the third layer in a direction intersecting the main surface of the electrode current collector, the second direction being different from the first direction and being a direction from the center towards the outer edge of the main surface of the electrode current collector, the electrode current collector, the first layer, the second layer, and the third layer being stacked in the stacked body.
17 . The battery manufacturing method according to claim 14 , further comprising: forming a cut surface at an end portion of a stacked body in a second direction by collectively cutting the electrode current collector, the first layer, the second layer, the third layer, and the counter electrode current collector in a direction intersecting the main surface of the electrode current collector, the second direction being different from the first direction and being a direction from the center towards the outer edge of the main surface of the electrode current collector, the electrode current collector, the first layer, the second layer, the third layer, and the counter electrode current collector being stacked in the stacked body.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This is a continuation application of PCT International Application No. PCT/JP2024/018302 filed on May 17, 2024, designating the United States of America, which is based on and claims priority of Japanese Patent Application No. 2023-106322 filed on Jun. 28, 2023. The entire disclosures of the above-identified applications, including the specifications, drawings and claims are incorporated herein by reference in their entirety. FIELD The present disclosure relates to batteries and battery manufacturing methods. BACKGROUND Patent Literature (PTL) 1 describes a battery in which an electrode current collector, an electrode active material layer, a solid electrolyte layer, a counter electrode active material layer, and a counter electrode current collector are stacked. PTL 2 describes a battery in which an electrode current collector, an electrode active material layer, a solid electrolyte layer, a counter electrode active material layer, and a counter electrode current collector are stacked. In addition, in the battery described in PTL 2, non-opposed sites are provided at the ends of the electrode active material layer and the solid electrolyte layer. PTL 3 describes a battery in which an electrode current collector, an electrode active material layer, a solid electrolyte layer, a counter electrode active material layer, and a counter electrode current collector are stacked. In addition, in the battery described in PTL 3, steps are provided in the electrode active material layer and the counter electrode active material layer, and an insulating layer is disposed on the counter electrode current collector. CITATION LIST Patent Literature PTL 1: Japanese Unexamined Patent Application Publication No. 2019-140079PTL 2: Japanese Unexamined Patent Application Publication No. 2020-129519PTL 3: Japanese Unexamined Patent Application Publication No. 2022-104137 SUMMARY Technical Problem In view of the above, the present disclosure provides a battery suitable for achieving both high resistance to short circuits and high efficiency productivity. Solution to Problem The battery according to one aspect of the present disclosure includes a unit cell including: an electrode current collector; a first layer disposed on a main surface of the electrode current collector; a second layer disposed on a side of the first layer opposite from the electrode current collector; a third layer disposed on a side of the second layer opposite from the first layer; and a counter electrode current collector disposed on a side of the third layer opposite from the second layer, wherein the first layer includes an electrode active material layer and a first insulating layer having an electronic insulation property, the first insulating layer being aligned with the electrode active material layer in a first direction that is a direction from a center of the main surface towards an outer edge of the main surface of the electrode current collector, the first insulating layer being disposed at an end portion of the first layer in the first direction, the second layer includes an electrolyte layer, the third layer includes a counter electrode active material layer, a first region not covered with the first layer is provided at an end portion of the main surface of the electrode current collector in the first direction, a second region not covered with the second layer in a plan view of the main surface of the electrode current collector is provided at the end portion of the first layer in the first direction, and a third region not covered with the third layer in the plan view is provided at an end portion of the second layer in the first direction. A battery manufacturing method includes: preparing an electrode current collector and stacking a first layer on a main surface of the electrode current collector to provide a first region not covered with the first layer at an end portion of the main surface of the electrode current collector in a first direction that is a direction from a center of the main surface towards an outer edge of the main surface of the electrode current collector; stacking a second layer on a side of the first layer opposite from the electrode current collector to provide a second region not covered with the second layer in a plan view of the main surface of the electrode current collector at an end portion of the first layer in the first direction; stacking a third layer on a side of the second layer opposite from the first layer to provide a third region not covered with the third layer in the plan view at an end portion of the second layer in the first direction; and stacking a counter electrode current collector on a side of the third layer opposite from the second layer, wherein the first layer includes an electrode active material layer and a first insulating layer having an electronic insulation property, the first insulating layer being aligned with the electrode active material l