Electrical energy storage device and method for its production

Abstract

The invention relates to an electrical energy storage device (1) designed as a prismatic battery cell (1), comprising a housing (2) and a cover (3) for closing the housing (2), wherein at least two terminals (4, 10) are arranged in the cover (3) and / or in the housing (2), wherein at least one of the terminals (4) is arranged electrically insulated from the cover (3) and / or the housing (2), wherein a crimp collar (6) is arranged on the cover (3) or on the housing (2), wherein one of the terminals (4) is arranged within the crimp collar (6), wherein an insulation element (5) made of an electrically insulating plastic is arranged between the crimp collar (6) and one of the terminals (4) and the cover (3) or housing (2) and one of the terminals (4), wherein the crimp collar (6) is bent over in the direction of the terminal (4) and the terminal (4) is clamped onto the cover (3) or housing (2).The invention further relates to a method for assembling the electrical energy storage device (1).

Description

[0001] The invention relates to an electrical energy storage device according to the preamble of claim 1.

[0002] The invention further relates to a method for assembling an electrical energy storage device according to the preamble of claim 10.

[0003] From EP 2 800 162 A1 an alkaline storage battery is known, comprising: - a cylindrical housing having a side wall comprising an open end portion and a bottom; - a sealing plate; - a seal arranged between the sealing plate and the opening end portion; and - a sealant between the seal and the opening end section.

[0004] The sidewall has an annular groove open on its outer surface and an inwardly curved portion at the opening end portion. The sealant comprises a polyamide resin shaped so that, when two test plate materials are bonded together, the resin is moved across an adhesive portion of the sealant parallel to the bonding surfaces and in opposite directions to create relative displacement within the sealant.

[0005] The invention is based on the object of providing a novel electrical energy storage device and a novel method for assembling an electrical energy storage device.

[0006] The object is achieved according to the invention by an electrical energy storage device which has the features specified in claim 1 and by a method which has the features specified in claim 10.

[0007] Advantageous embodiments of the invention are the subject of the subclaims.

[0008] An electrical energy storage device is proposed, designed as a prismatic battery cell, comprising a housing and a cover for closing the housing, wherein at least two terminals are arranged in the cover and / or in the housing, wherein at least one of the terminals is arranged electrically insulated from the cover and / or housing. According to the invention, a crimp collar is arranged on the cover or on the housing, wherein one of the terminals is arranged within the crimp collar, wherein an insulation element made of an electrically insulating plastic is arranged between the crimp collar and one of the terminals and between the cover or housing and one of the terminals, wherein the crimp collar is bent over in the direction of the terminal and clamps the terminal onto the cover or housing.

[0009] In one embodiment, the cover or the housing has a recess for the terminal, wherein the crimp collar is arranged circumferentially around the recess.

[0010] In one embodiment, a bursting element and / or a closure unit for the electrolyte opening can be arranged in a recess of the housing, with a crimp collar arranged circumferentially around the recess. In one embodiment, however, at least one of these two elements can also be included in the terminal itself.

[0011] In one embodiment, the crimp collar is arranged at a distance around the recess to form a shoulder for placing the insulation element.

[0012] In one embodiment, the insulation element has a flat area with a recess which lies in a plane and is arranged parallel to the cover or housing, so that the recess in the flat area is aligned with the recess in the cover, wherein a circumferential collar protrudes from the flat area (for example at a right angle) and is arranged within the crimp collar.

[0013] An outer contour of the circumferential collar can be designed to correspond to an inner contour of the crimp collar.

[0014] The terminal may have an outer contour that corresponds to an inner contour of the collar of the insulation element.

[0015] In one embodiment, one or more steps, flanges, thickened portions, elevations, or depressions can be arranged in an edge region of the terminal. The edge regions can also be roughened, for example, by chemical processes or laser ablation.

[0016] The step, flange, thickening, elevation, or depression can, for example, be provided only at the edge areas of the long sides of the elongated terminal or circumferentially around the entire terminal. Likewise, the geometry or type can vary depending on the position (e.g., lower along the long sides than along the radii).

[0017] The terminal can be made of an electrically conductive material and, for example, have a material thickness of 0.3 mm to 2 mm.

[0018] The housing and / or the cover may be made of an electrically conductive material.

[0019] The electrically conductive material of the terminal may contain copper.

[0020] In one embodiment, the insulation element may be formed from polyethylene terephthalate and / or polypropylene and / or provided with an elastomeric coating.

[0021] In one embodiment, the insulation element can be formed as an injection-molded part.

[0022] In one embodiment, the terminal may be configured as a rectangular terminal with rounded corners, an elongated terminal with two semicircular ends, an oval terminal, or a circular terminal. Likewise, the terminal may have rounded ends and inwardly curved sides.

[0023] In one embodiment, the terminal may contain copper and / or be formed as a stamped or embossed part.

[0024] The cover or housing can be manufactured, for example, by extrusion, deep drawing, punching and / or embossing and can be made of aluminum.

[0025] According to one aspect of the present invention, a method for assembling the electrical energy storage device is proposed, wherein the insulating element is placed on the shoulder within the crimp collar, wherein the terminal is inserted within the collar of the insulating element, wherein the crimp collar, the insulating element and the terminal are then connected to one another in a form-fitting and gas-tight manner by crimping, that is to say bending the crimp collar inwards and the resulting bending of the insulating element inwards, wherein the crimp collar and the terminal remain electrically insulated from one another by the insulating element.

[0026] The present invention provides a cost-effective, gas-tight, and electrically insulating connection between a terminal and a cover and / or housing of a prismatic hard-case cell by crimping. The housing wall or a projection on the cover is bent inward. This deformation also bends an electrically insulating plastic, clamping the terminal in place. The terminal is thus positively secured, and a gas-tight closure of the cell is achieved.

[0027] The inventive solution comprises a small number of parts to create a closed, gas-tight battery cell: the housing, the cover, the insulation element, and the terminal. Assembly and crimping are a quick and cost-effective process. Compared to previous solutions, which usually involve laser welding, bonding, and riveting, this solution offers significant advantages.

[0028] Embodiments of the invention are explained in more detail below with reference to drawings.

[0029] Showing: Fig. 1 a schematic view of a prismatic battery cell with two terminals, Fig. 2 schematic views of possible cross-sectional shapes of the terminals, Fig. 3 a schematic sectional view of one of the terminals, Fig. 4 a schematic view of one of the lids of the battery cell with a recess for the terminal, Fig. 5 a schematic view of an insulation element, Fig. 6 a schematic view of the terminal, and Fig. 7 a schematic exploded view of the battery cell.

[0030] Corresponding parts are provided with the same reference numerals in all figures.

[0031] Fig. Figure 1 is a schematic view of an electrical energy storage device 1 in the form of a prismatic battery cell 1, in particular a hardcase cell. The battery cell 1 has a housing 2 and a cover 3 for the upper closure of the housing 2. Two electrical terminals 4, 10 are arranged in the cover 3. In an embodiment not shown, one of the terminals 4, 10 or both electrical terminals 4, 10 can be arranged in the housing 2.

[0032] Fig. Figure 2 schematically shows possible cross-sectional shapes of the terminals 4, 10, for example a rectangular terminal 4.1 with rounded corners, an elongated terminal 4.2 with two semicircular ends, an oval terminal 4.3 and a circular terminal 4.4.

[0033] Fig. 3 is a schematic sectional view of one of the terminals 4 of Fig. 1. To connect terminal 4 to housing 2 or cover 3, a projection 6 on the housing 2, in particular on a housing wall, or a projection 6 on the cover 3 is bent inward, i.e., toward terminal 4. This deformation also bends an insulating element 5 made of a flexible, electrically insulating plastic, which is arranged between the projection 6 and terminal 4, and clamps terminal 4 securely. Terminal 4 is thus positively fixed, and a gas-tight seal of battery cell 1 is achieved.

[0034] Fig. 4 is a schematic view of the cover 3 with a recess 7 for the terminal 4. For an insulated crimp connection between the cover 3 and terminal 4, the cover 3 has the projection 6 or crimp collar 6 around the recess 7 for the terminal 4, which can be formed circumferentially around the recess 7. The crimp collar 6 can be arranged at a distance around the recess 7, so that a shoulder 8 is formed between the recess 7 and the crimp collar 6, on which the insulating element 5 made of the electrically insulating plastic can rest. The crimp collar 6 can be attached to a surface of the cover 3.

[0035] Fig. 5 is a schematic view of the insulating element 5. The insulating element 5 can have a flat region 5.1 with a recess 5.2, which lies in a plane and is arranged parallel to the cover 3, so that the recess 5.2 in the flat region 5.1 is aligned with the recess 7 in the cover 3. A circumferential collar 5.3 protrudes from the flat region 5.1 at approximately a right angle, in particular inclined outwards by approximately 87°, and is arranged within the crimp collar 6. An outer contour of the circumferential collar 5.3 can be designed to correspond to an inner contour of the crimp collar 6.

[0036] Fig. Figure 6 is a schematic view of Terminal 4.

[0037] For assembly, the insulation element 5 is placed on the shoulder 8 within the crimp collar 6. The terminal 4 is then inserted within the collar 5.3 of the insulation element 5. The terminal 4 can have an outer contour that corresponds to an inner contour of the collar 5.3 of the insulation element 5.

[0038] Subsequently, the cover 3, the insulation element 5 and the terminal 4 are connected to one another in a form-fitting and gas-tight manner by crimping with the crimp collar 6, i.e. bending the crimp collar 6 inwards and thereby also bending the insulation element 5 inwards, whereby the crimp collar 6 and the terminal 4 remain electrically insulated from one another by the insulation element 5.

[0039] A step 9, flange 9 or thickening 9 or elevation can be arranged in an edge region of the terminal 4 in order to stabilize the crimp connection against mechanical influences such as cell thickness growth.

[0040] The other terminal 10 may be part of the material of the cover 3 or the housing 2.

[0041] The housing 2 and / or the cover 3 are / are made of an electrically conductive material. The terminal 4 is made of an electrically conductive material and can, for example, have a material thickness of 0.3 mm to 2 mm. The electrically conductive material of the terminal 4 can have a copper content, which can depend on the desired current-carrying capacity and the pressure conditions inside the battery cell 1. Alternatively, it is also conceivable that the material pairing could be reversed, i.e., NPS on the housing 2 and aluminum on the terminal 4.

[0042] The illustrated embodiment comprises a small number of parts to create a closed, gas-tight battery cell 1: the housing 2, the cover 3, the insulation element 5, and the terminal 4. Assembly and crimping are a fast and cost-effective process. Compared to previous solutions, which usually involve laser welding, bonding, and riveting, this solution offers significant advantages.

[0043] The insulation element 5 can be formed, for example, from polyethylene terephthalate (PETP) and / or polypropylene (PP) and manufactured as an injection-molded part. The insulation element 5 can also be provided with an elastomeric coating. The terminal 4 can contain copper and be formed as a stamped or embossed part. The cover 3 can be manufactured, for example, by extrusion, stamping, and / or embossing and can be made of aluminum.

[0044] The crimp collar 6 can, for example, have an inner contour in the shape of an elongated hole, a curved elongated hole, or an oval. The shape can be adapted to the prismatic housing 2. The crimp can be provided within the cover 3 (local crimp) or between the cover 3 and the housing 2.

[0045] The terminal 4 has a step 9, flange 9, thickening 9, or elevation in its edge areas to enable an additional undercut to stabilize the crimp connection against mechanical influences such as cell thickness growth. The step 9, flange 9, thickening 9, or elevation can, for example, be provided only in the edge areas of the long sides of the elongated terminal 4 or circumferentially around the entire terminal 4.

[0046] Fig. 7 is a schematic exploded view of the battery cell 1. List of reference symbols 1 electrical energy storage device, battery cell 2 housings 3 lids 4, 4.1 to 4.4 Terminal 5 Insulation element 5.1 flat area 5.2 Recess 5.3 Collar 6 Overhang, crimp collar 7 Recess 8 paragraph 9 stage, flanging, thickening 10 Terminal QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 2 800 162 A1

[0003]

Claims

[1] Electrical energy storage device (1), designed as a prismatic battery cell (1), comprising a housing (2) and a cover (3) for closing the housing (2), wherein at least two terminals (4, 10) are arranged in the cover (3) and / or in the housing (2), wherein at least one of the terminals (4) is arranged electrically insulated from the cover (3) and / or the housing (2), characterized by that a crimp collar (6) is arranged on the cover (3) or on the housing (2), wherein one of the terminals (4) is arranged within the crimp collar (6), wherein an insulation element (5) made of an electrically insulating plastic is arranged between the crimp collar (6) and one of the terminals (4) and the cover (3) or housing (2) and one of the terminals (4), wherein the crimp collar (6) is bent over in the direction of the terminal (4) and the terminal (4) is clamped onto the cover (3) or housing (2). [2] Electrical energy storage device (1) according to claim 1, characterized bythat the cover (3) or the housing (2) has a recess (7) for the terminal (4), wherein the crimp collar (6) is arranged circumferentially around the recess (7). [3] Electrical energy storage device (1) according to claim 2, characterized by that the crimp collar (6) is arranged at a distance around the recess (7) to form a shoulder (8) for placing the insulation element (5). [4] Electrical energy storage device (1) according to one of claims 2 or 3, characterized by that the insulation element (5) has a flat area (5.1) with a recess (5.2), which lies in a plane and is arranged parallel to the cover (3) or housing (2), so that the recess (5.2) in the flat area (5.1) is aligned with the recess (7) in the cover (3), wherein a circumferential collar (5.3) projects from the flat area (5.1) approximately at a right angle and is arranged within the crimp collar (6). [5] Electrical energy storage device (1) according to one of the preceding claims, characterized by that a thickening (9) is arranged in an edge region of the terminal (4). [6] Electrical energy storage device (1) according to one of the preceding claims, characterized by that the insulating element (5) is made of polyethylene terephthalate (PETP) and / or polypropylene (PP) and / or is provided with an elastomeric coating. [7] Electrical energy storage device (1) according to one of the preceding claims, characterized by that the insulation element (5) is designed as an injection-molded part. [8] Electrical energy storage device (1) according to one of the preceding claims, characterized by that the terminal (4) is designed as a rectangular terminal (4.1) with rounded corners, as an elongated terminal (4.2) with two semicircular ends, as an oval terminal (4.3) or as a circular terminal (4.4). [9] Electrical energy storage device (1) according to one of the preceding claims, characterized by that the terminal (4) contains copper and is designed as a stamped or embossed part. [10] Method for assembling the electrical energy storage device (1) according to one of the preceding claims, characterized by that the insulation element (5) is placed on the shoulder (8) within the crimp collar (6), wherein the terminal (4) is inserted within the collar (5.3) of the insulation element (5), wherein the crimp collar (6), the insulation element (5) and the terminal (4) are then connected to one another in a form-fitting and gas-tight manner by crimping, that is to say by bending the crimp collar (6) inwards and the resulting bending of the insulation element (5), wherein the crimp collar (6) and the terminal (4) remain electrically insulated from one another by the insulation element (5).

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