Energy storage device and method for manufacturing energy storage device
An energy storage device includes an electrode body and an outer packaging. The outer packaging seals the electrode body. The outer packaging is constituted by a film-like outer packaging member. The outer packaging includes a first sealing portion sealed by joining surfaces that face each other in a state in which the outer packaging member is wrapped around the electrode body. A base portion of the first sealing portion is formed at the boundary between a first surface and a second surface of the outer packaging. The first surface has a larger area than the second surface. The first sealing portion does not overlap the first surface in a plan view.
1 . An energy storage device comprising:
an electrode body; and
an outer packaging that seals the electrode body, wherein
the outer packaging includes:
a film-like outer packaging member wound around the electrode body to have an opening,
a lid body fitted into the opening, and
a first sealing portion that is sealed by joining surfaces that face each other in a state in which the outer packaging member is wrapped around the electrode body,
a base portion of the first sealing portion is at a boundary between a first surface and a second surface of the outer packaging,
the first surface has a larger area than the second surface,
the first sealing portion does not overlap the first surface in a plan view, and
the lid body is a resin-molded or metal-molded product.
2 . The energy storage device according to claim 1 ,
wherein the first sealing portion is bent to be in contact with the second surface.
3 . The energy storage device according to claim 2 ,
wherein the first sealing portion covers substantially the entire second surface in a state in which the first sealing portion is bent to be in contact with the second surface.
4 . The energy storage device according to claim 1 , further comprising:
an electrode terminal that is electrically connected to the electrode body,
wherein the outer packaging further includes a second sealing portion sealed in a state of holding the electrode terminal,
a portion of the electrode terminal is outside of the outer packaging, and
a base portion of the portion of the electrode terminal is at a position at approximately half of the thickness of the energy storage device in a thickness direction of the energy storage device.
5 . The energy storage device according to claim 1 ,
wherein a region where a joining force between the surfaces is strong and a region where the joining force between the surfaces is weak are side-by-side along the boundary in the first sealing portion.
6 . The energy storage device according to claim 1 ,
wherein a thin region and a thick region are side-by-side along the boundary in the first sealing portion.
7 . The energy storage device according to claim 1 , further comprising:
an electrode terminal that is electrically connected to the electrode body,
wherein the first sealing portion is sealed in a state of holding the electrode terminal.
8 . The energy storage device according to claim 1 , further comprising:
an electrode terminal that is electrically connected to the electrode body; wherein
the electrode terminal is attached to the lid body, and
the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body.
9 . The energy storage device according to claim 8 ,
wherein the lid body includes a first surface facing the electrode body and a second surface that is opposite to the first surface, and
the second sealing portion includes a portion where the outer packaging and the second surface are joined together.
10 . The energy storage device according to claim 1 ,
wherein the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body,
the lid body includes a metal portion that is where a metal layer is exposed on a surface of the lid body or that is made of a metal material, and
the metal portion and the electrode body are welded to each other.
11 . The energy storage device according to claim 1 , further comprising:
an electrode terminal that is electrically connected to the electrode body,
wherein the outer packaging further includes an extending portion that protrudes outward and a second sealing portion sealed in a state in which the electrode terminal is held by the extending portion.
12 . The energy storage device according to claim 1 ,
wherein a direction extending along the boundary is orthogonal to a machine direction of the outer packaging member.
13 . An energy storage device comprising:
an electrode body; and
an outer packaging that seals the electrode body, wherein
the outer packaging is constituted by a film-like outer packaging member,
the outer packaging includes a piece in which peripheral edges of surfaces that face each other are joined together in a state in which the outer packaging member is wrapped around the electrode body,
a base portion of the piece is at a boundary between surfaces of the outer packaging,
a space in which the surfaces that face each other are not joined is in the piece,
in the piece, a region in which the surfaces that face each other are joined together and a region in which the surfaces that face each other are not joined are side-by-side in a vicinity of the boundary, and
in the region in which the surfaces that face each other are not joined, opposing inner surfaces of the outer packaging member face each other directly without any intervening element.
14 . A method for manufacturing an energy storage device from an unfinished product,
the unfinished product including
an electrode body, and
an outer packaging that seals the electrode body,
the outer packaging being constituted by a film-like outer packaging member,
the outer packaging including a piece in which peripheral edges of surfaces that face each other are joined together in a state in which the outer packaging member is wrapped around the electrode body,
a base portion of the piece being at a boundary between surfaces of the outer packaging,
a space in which the surfaces that face each other are not joined being in the piece, and
in the piece, a region in which the surfaces that face each other are joined together and a region in which the surfaces that face each other are not joined being side-by-side in a vicinity of the boundary,
the manufacturing method comprising:
unsealing the outer packaging with use of the piece and discharging gas from the outer packaging; and
resealing the outer packaging by joining the surfaces that face each other in at least a portion of the piece.
15 . The energy storage device according to claim 13 , further comprising:
an electrode terminal that is electrically connected to the electrode body; and
a lid body to which the electrode terminal is attached, wherein
the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body,
the lid body includes a first surface facing the electrode body and a second surface that is opposite to the first surface, and
the second sealing portion includes a portion where the outer packaging and the second surface are joined together.
16 . The energy storage device according to claim 13 , further comprising:
a lid body, wherein
the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body,
the lid body includes a metal portion that is where a metal layer is exposed on a surface of the lid body or that is made of a metal material, and
the metal portion and the electrode body are welded to each other.
17 . A method for manufacturing an energy storage device from an unfinished product, according to claim 14 , wherein
the unfinished product includes
an electrode terminal that is electrically connected to the electrode body, and
a lid body to which the electrode terminal is attached,
the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body,
the lid body includes a first surface facing the electrode body and a second surface that is opposite to the first surface, and
the second sealing portion includes a portion where the outer packaging and the second surface are joined together.
18 . A method for manufacturing an energy storage device from an unfinished product, according to claim 14 , wherein
the unfinished product includes a lid body,
the outer packaging further includes a second sealing portion sealed in a state of being joined to the lid body,
the lid body includes a metal portion that is where a metal layer is exposed on a surface of the lid body or that is made of a metal material, and
the metal portion and the electrode body are welded to each other.
19 . The energy storage device according to claim 1 ,
wherein the lid body is a tray-shaped member having a bottom and a rectangular shape in a plan view.
20 . The energy storage device according to claim 1 ,
wherein the lid body has a plate shape.
21 . The energy storage device according to claim 1 ,
wherein the lid body has a member that is divided into a plurality of parts so that holes are formed through which electrode terminal can be placed.