JP2019175613A - Battery and housing member - Google Patents

Abstract

To provide a battery with a novel configuration, capable of reducing labor for removing an electrolyte adhering to the outer surface of a lid member.SOLUTION: A battery of an embodiment includes a housing, a wall part, an uneven part, a lid, and a welded part. The housing houses an electrode body and an electrolyte therein. The wall part configures the housing, and has an outer surface facing the outside of the housing and an inner surface facing the inside of the housing. The wall part is provided with a through hole opening to the outer surface and the inner surface. The uneven part has a plurality of projecting portions provided in a distributed manner around the edge of the through hole. The lid is overlaid on the uneven part and closes the through hole. The welded part surrounds the edge and joins the lid with the wall part.SELECTED DRAWING: Figure 4

Description

  Embodiments described herein relate generally to a battery and a casing member.

  Conventionally, a sealed battery such as a lithium ion battery is known. The case of this type of battery has, for example, a case having an open upper end and a lid member that is welded so as to close the opening of the case. And before welding a cover member to a case, a battery element is arrange | positioned in a case, and a cover member is welded to a case after that, and a housing | casing is manufactured. Next, an electrolytic solution is injected into the housing through a liquid injection port provided in the lid member. Then, after pouring the electrolytic solution, the injection port is closed with a lid, and the lid is welded to the lid member.

JP 2014-41770 A

  In the above structure, when the electrolytic solution adheres to the outer surface of the lid member, it is necessary to perform welding after removing the electrolytic solution by suction or wiping, for example, which is troublesome. In view of this, in this type of battery, it is preferable if the effort required to remove the electrolyte attached to the outer surface of the lid member can be reduced.

  The battery of the embodiment includes a housing, a wall portion, an uneven portion, a lid, and a welded portion. The housing contains an electrode body and an electrolytic solution. The wall portion constitutes the casing, and has an outer surface facing the outside of the casing and an inner surface facing the inside of the casing. The wall portion is provided with a through hole that opens to the outer surface and the inner surface. The concavo-convex part has a plurality of convex parts provided in a distributed manner around the edge of the through hole. The lid is stacked on the uneven portion and closes the through hole. The welded portion surrounds the edge and joins the lid and the wall portion.

It is an exemplary and typical appearance perspective view of a battery of an embodiment. It is an exemplary and schematic plan view of the periphery of the sealing lid of the housing provided in the battery of the embodiment. FIG. 3 is an exemplary schematic cross-sectional view taken along the line III-III in FIG. 2 of the embodiment. It is an exemplary and schematic top view of the uneven | corrugated | grooved part of the battery of embodiment. It is a flowchart which shows an example of the manufacturing process of the battery of embodiment.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

  As shown in FIG. 1, the battery 1 includes an electrode body 2, a housing 3 that houses the electrode body 2 together with an electrolytic solution, and a positive electrode terminal 4 and a negative electrode terminal 5 that are a pair of electrode terminals. Examples of the battery 1 include nonaqueous electrolyte batteries (secondary batteries) such as lithium ion batteries.

  The electrode body 2 is formed by winding a positive electrode sheet and a negative electrode sheet, which are power generation elements, in a spiral shape via a separator, and is housed in the housing 3 together with an electrolytic solution. The electrolytic solution is volatile.

  The housing | casing 3 has a flat rectangular parallelepiped shape, for example, is comprised with metals, such as aluminum or aluminum alloy. The housing 3 includes a case 3a whose one end (upper end in FIG. 1) is open, and a rectangular plate-like lid member 3b that closes the opening at one end of the case 3a. The lid member 3b is a case. It is welded to 3a and formed fluid-tight. The lid member 3b is an example of a wall portion and a housing member. Case 3a is also referred to as a container.

  The positive electrode terminal 4 is provided at one end portion in the longitudinal direction of the lid member 3b, and the negative electrode terminal 5 is provided at the other end portion in the longitudinal direction of the lid member 3b. The positive electrode terminal 4 and the negative electrode terminal 5 are connected to the positive electrode and the negative electrode of the electrode body 2, respectively, and protrude from the upper surface of the lid member 3b. One of the terminals, for example, the positive electrode terminal 4 is electrically connected to the lid member 3b and has the same potential as that of the housing 3. The negative electrode terminal 5 extends through the lid member 3b. Between the negative electrode terminal 5 and the lid member 3b, a sealing material made of an insulator such as synthetic resin or glass, for example, a gasket (not shown). Is provided. This sealing material hermetically seals between the negative electrode terminal 5 and the housing 3 and is electrically insulated.

  For example, a rectangular safety valve 6 is provided at the center of the lid member 3b. The safety valve 6 is formed by thinning a part of the lid member 3b to about half the thickness, and a stamp is formed at the center of the upper surface of the thin part. When the gas is generated in the housing 3 and the internal pressure of the housing 3 increases to a predetermined value or more, the safety valve 6 is opened to release the gas in the housing 3 and reduce the internal pressure of the housing 3. .

  As shown in FIGS. 1 to 3, the lid member 3 b has an outer surface 3 c facing the outside of the housing 3 and an inner surface 3 d facing the inside of the housing 3. In addition, a liquid injection port 7 is provided in the lid member 3b. The liquid injection port 7 is a through-hole penetrating the lid member 3b in the thickness direction of the lid member 3b. That is, the liquid injection port 7 opens to the outer surface 3c and the inner surface 3d. The liquid injection port 7 is formed in a circular shape as an example. An electrolytic solution is injected into the housing 3 from the liquid injection port 7. The liquid injection port 7 is an example of a through hole.

  As shown in FIGS. 3 and 4, the lid member 3 b is provided with an uneven portion 8. The concavo-convex portion 8 is provided in a substantially annular region R1 (FIG. 4) surrounding the liquid injection port 7. In FIG. 4, the region R1 is a region surrounded by two circular lines L2.

  As shown in FIG. 3, the concavo-convex portion 8 is provided with a plurality of convex portions 8a and a plurality of concave portions 8b. The concave portion 8b is formed between two adjacent convex portions 8a. The convex part 8a protrudes with respect to the bottom part of the concave part 8b. Moreover, in this embodiment, as FIG. 4 shows, the some convex part 8a and the recessed part 8b are provided on the some line L1 which makes a grid | lattice form. A plurality of convex portions 8a are provided on each line L1 at intervals, and a concave portion 8b is provided between the convex portions 8a and 8a. The plurality of recesses 8b may be formed continuously and may constitute one lattice-shaped recess, or may be partitioned from each other. As can be seen from the above, in the present embodiment, at least the convex portions 8a among the plurality of convex portions 8a and the plurality of concave portions 8b are distributed around the edge 7a of the liquid injection port 7 on the outer surface 3c. In other words, the plurality of convex portions 8a are discretely positioned. In FIG. 4, the convex portion 8a is shown in a dot shape, but the shape of the convex portion 8a can be variously set. That is, specifications such as the diameter, width, and length of the shape of the convex portion 8a can be variously set. The uneven portion 8 is also referred to as a diffusion portion.

  As shown in FIGS. 3 and 4, the uneven portion 8 is separated from the edge 7 a of the liquid injection port 7. That is, a flat portion 3 e is provided on the outer surface 3 c between the uneven portion 8 and the edge 7 a of the liquid injection port 7. The width of the flat portion 3e, that is, the distance between the inner peripheral edge of the uneven portion 8 and the edge 7a of the liquid injection port 7 is, for example, 1 mm or more. In addition, the distance between the inner periphery of the uneven | corrugated | grooved part 8 and the edge 7a of the injection hole 7 may be less than 1 mm.

  The concavo-convex portion 8 is formed by, for example, laser processing by laser light irradiation. The laser beam is, for example, a pulsed laser beam. The concavo-convex portion 8 may be formed by a process such as chemical etching using masking, or may be formed by machining or the like.

  As shown in FIGS. 2 and 3, a sealing lid 9 that closes the liquid injection port 7 is joined (fixed) to the lid member 3 b by a welded portion 10. The lid member 3b is joined to the lid member 3b in a state where the lid member 3b is overlapped with the concavo-convex portion 8. The sealing lid 9 is an example of a lid.

  The sealing lid 9 is made of a metal such as aluminum or an aluminum alloy, for example. The sealing lid 9 is formed in a circular shape, for example, and the diameter thereof is the same as the diameter of the concavo-convex portion 8, for example. In addition, the diameter of the sealing lid 9 may be larger or smaller than the diameter of the uneven portion 8.

  As shown in FIGS. 2 and 3, the welded portion 10 is configured in an annular shape surrounding the edge 7 a of the liquid injection port 7. As shown in FIG. 3, the welded portion 10 is provided between the inner peripheral portion and the outer peripheral portion of the concavo-convex portion 8. That is, the plurality of convex portions 8a and the plurality of concave portions 8b are provided on the outer surface 3c on the side of the liquid injection port 7 of the welded portion 10 and on the side of the outer surface 3c opposite to the liquid injection port 7 of the welded portion 10, respectively. The welding part 10 is a penetration part formed by laser welding, for example, and is also called a welding trace.

  Next, a method for manufacturing the battery 1 will be described.

  As shown in FIG. 5, first, an electrolytic solution is injected from the liquid injection port 7 into the housing 3 using an electrolytic solution injection device (not shown) (S <b> 1). Thereafter, the casing 3 into which the electrolytic solution has been injected is supplied to a laser irradiation device (not shown) (S2).

Next, the ambient atmosphere of the housing 3 into which the electrolytic solution has been injected is reduced (S3). The entire housing 3 or only the upper part where the sealing lid 9 is located is confined in a sealed space, that is, a chamber of the laser irradiation apparatus. The atmosphere of the sealed space in the chamber is reduced to 20 kPa, for example, in an N ₂ atmosphere.

  Next, the sealing lid 9 is placed on the concavo-convex portion 8 at a position where the liquid injection port 7 is blocked by a mounting device (not shown) such as a robot (S4).

  Next, the sealing lid 9 is laser-welded and fixed to the lid member 3b of the housing 3 in the above-described reduced pressure state (S5). Specifically, a laser irradiation device (not shown) irradiates the outer surface 9a (FIG. 3) positioned on the side opposite to the lid member 3b of the sealing lid 9 in an annular shape. Thereby, a laser beam is irradiated in the annular | circular shape along the edge 7a of the injection hole 7, the sealing lid | cover 9 is welded to the cover member 3b, and the welding part 10 is formed. Finally, a predetermined inspection such as a shipping test is performed (S6).

  In the manufacturing method of the battery 1, the electrolyte may adhere to the outer surface 3c of the lid member 3b when the electrolyte of S1 is injected. At this time, for example, the electrolyte adhering to the uneven portion 8 is spread thinly by the uneven portion 8. In other words, the electrolytic solution is diffused in the uneven portion 8. Specifically, the electrolytic solution that has entered the concave portion 8b between the convex portions 8a, that is, the concave portions 8b moves and spreads in the concave and convex portions 8 by capillary action by the plurality of convex portions 8a. Since the electrolyte spread in this way has a larger surface area than before spreading, it easily evaporates accordingly. Therefore, the electrolytic solution evaporates in a relatively short time. In the present embodiment, the time from when the electrolyte solution is injected until the sealing lid 9 is placed is the time required for the specified amount of electrolyte solution attached to the concavo-convex portion 8 to evaporate. Is set longer than. That is, the process from the injection of the electrolytic solution to just before the sealing lid 9 is placed constitutes the step of evaporating the electrolytic solution adhering to the uneven portion 8.

  As described above, in the present embodiment, the battery 1 includes the housing 3, the lid member 3 b (wall portion), the uneven portion 8, the sealing lid 9, and the welded portion 10. The housing 3 accommodates the electrode body 2 and the electrolytic solution. The lid member 3 b constitutes the housing 3 and has an outer surface 3 c facing the outside of the housing 3 and an inner surface 3 d facing the inside of the housing 3. The lid member 3b is provided with a liquid injection port 7 (through hole) that opens to the outer surface 3c and the inner surface 3d. The concavo-convex portion 8 has a plurality of convex portions 8a provided in a distributed manner around the edge 7a of the liquid injection port 7 on the outer surface 3c. The sealing lid 9 is stacked on the concavo-convex portion 8 and closes the liquid injection port 7. The welded portion 10 surrounds the edge 7a and joins the sealing lid and the lid member 3b. Therefore, for example, when the electrolytic solution adheres to the concavo-convex portion 8 of the outer surface 3c of the lid member 3b during the injection of the electrolytic solution in the manufacture of the battery 1, the concavo-convex portion 8 spreads the electrolytic solution. The liquid can be evaporated in a relatively short time. Therefore, for example, the suction and wiping work for removing the electrolytic solution adhering to the uneven portion 8 can be omitted. Therefore, it is possible to reduce the labor required to remove the electrolytic solution adhering to the outer surface 3c of the lid member 3b.

  Moreover, in this embodiment, the some convex part 8a is provided in each of the injection surface 7 side of the welding part 10 in the outer surface 3c, and the opposite side to the injection hole 7 of the welding part 10 in the outer surface 3c. Therefore, compared with the case where a plurality of convex portions 8a are provided only on one of the liquid injection port 7 side of the welded portion 10 on the outer surface 3c and the side opposite to the liquid injection port 7 of the welded portion 10 on the outer surface 3c, It is easier to evaporate the electrolyte.

  In the present embodiment, the uneven portion 8 is separated from the liquid injection port 7. Therefore, compared with the case where the concavo-convex portion 8 is provided adjacent to the liquid injection port 7, in the manufacture of the battery 1, the electrolyte injected into the housing 3 is injected before the sealing lid 9 is placed. Even when the peripheral surface of the liquid port 7 is moved upward, it is easy to suppress the electrolyte from coming out to the outer surface 3c.

  In the above-described embodiment, the example in which the convex portions 8d are provided on the plurality of lines L1 having a lattice shape is shown, but the present invention is not limited to this. For example, a plurality of convex portions 8d may be provided on a plurality of lines radially positioned around the liquid injection port 7. Moreover, the convex part 8d may be arrange | positioned at random around the injection hole 7, not regularly.

  Moreover, in the said embodiment, although the example in which the liquid injection port 7 and the uneven | corrugated | grooved part 8 were provided in the cover member 3b was shown, the liquid injection port 7 and the uneven | corrugated | grooved part 8 are wall parts of case 3a (housing | housing member). May be provided.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Electrode body, 3 ... Housing | casing, 3b ... Lid member (wall, housing member), 3c ... Outer surface, 3d ... Inner surface, 7 ... Injection hole (through-hole), 7a ... Edge, 8 ... Uneven portion, 8a ... convex portion, 9 ... sealing lid (lid), 10 ... welded portion.

Claims (5)

A housing containing an electrode body and an electrolytic solution;
A wall portion that constitutes the housing, has an outer surface facing the outside of the housing and an inner surface facing the inside of the housing, and is provided with a through hole opened in the outer surface and the inner surface;
An uneven portion having a plurality of protrusions provided dispersed around the edge of the through hole on the outer surface;
A lid that is overlaid on the concavo-convex portion and closes the through hole;
A weld that surrounds the edge and joins the lid and the wall;
With battery.   The battery according to claim 1, wherein a plurality of the convex portions are provided on each of the welded portion on the outer surface on the through hole side and on the outer surface on the opposite side of the welded portion on the outer surface.   The battery according to claim 1, wherein the uneven portion is separated from the through hole. A housing member that constitutes a battery housing containing an electrode body and an electrolyte solution,
An outer surface facing the outside of the housing;
An inner surface facing the interior of the housing;
An uneven portion provided on the outer surface and having a plurality of convex portions;
With
A through hole opened in the outer surface and the inner surface is provided,
The housing member, wherein the plurality of convex portions are provided distributed around the edge of the through hole on the outer surface.   The casing member according to claim 4, wherein the uneven portion is separated from the through hole.

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