Deformable busbar assembly

Abstract

Busbar assembly (10) comprising: a deformable busbar (1) with a busbar slot (5) separating a busbar positive pole flange (3) and a busbar negative pole flange (4), whereby the two flanges (3, 4) can move independently of each other, the busbar assembly (10) further comprising a deformable busbar frame (11) with a busbar frame flange connector (14) connecting a busbar frame positive pole flange (12) and a busbar frame negative pole flange (13) of the busbar frame (11), characterized in that the busbar assembly (10) further comprises a busbar frame flange slot (15) separating the busbar frame positive pole flange (12) and the busbar frame negative pole flange (13) at the busbar frame flange connector (14) of the busbar frame (11).

Description

FIELD OF INVENTION

[0001] Illustrative embodiments of the disclosure generally relate to electrical bus bars for electric vehicles (EVs). Illustrative embodiments of the disclosure more particularly relate to a deformable bus bar assembly and bus bar installation method that compensate for height differences between adjacent terminals on an HV battery. GENERAL STATE OF THE ART

[0002] Busbars for HV (Hybrid Vehicle) battery arrays can be attached to the battery cells using pins. Nuts can be threaded onto the studs and tightened to form a strong, electrically conductive connection. The studs can be used to position the busbars in the correct location for contact between the busbars and the cell terminal on the battery cell.

[0003] In some applications, it may be desirable to attach the busbars to the battery cell by welding them to the cell terminals. However, there may be height differences between the positive and negative terminals on the battery cell. This can leave gaps between the busbars and the terminals, compromising the integrity of the welds securing the busbars to the cell terminals.

[0004] Accordingly, a deformable busbar assembly and busbar installation method that compensates for height differences between adjacent poles on an HV battery may be desirable.

[0005] The documents DE 10 2010 019 708 A1, DE 10 2009 058 723 A1, US 2012 / 0100761 A1, and US 2006 / 0270277 A1 each disclose storage cell connectors comprising a first connection part for connecting to a first cell terminal and a second connection part for connecting to a second cell terminal, as well as a connecting part arranged between the connection parts. The document DE 20 2013 009 263 U1 discloses a circuit board for connecting stacked battery button cells in series. BRIEF DESCRIPTION OF THE INVENTION

[0006] According to the invention, a busbar assembly according to claim 1 and a busbar assembly according to claim 8 are proposed. Advantageous embodiments of the invention are specified in the dependent claims and the following description. Illustrative embodiments of the disclosure generally relate to a deformable busbar assembly that compensates for height differences between adjacent terminals on an HV battery. An illustrative embodiment of the busbar assembly includes a deformable busbar having a positive busbar terminal flange, a negative busbar terminal flange spaced from the positive busbar terminal flange, and a flange connecting portion connecting the positive busbar terminal flange and the negative busbar terminal flange.A busbar frame includes a busbar frame positive pole flange supported by the busbar positive pole flange of the deformable busbar and a busbar frame negative pole flange supported by the busbar negative pole flange of the deformable busbar.

[0007] Illustrative embodiments of the disclosure further generally relate to a method for installing a deformable bus bar on a positive and negative terminal of a battery cell. An illustrative embodiment of the method includes placing spaced-apart bus bar positive and negative terminal flanges of a deformable bus bar on the positive and negative terminals of the battery cell, respectively, and applying pressure against one of the bus bar positive and negative terminal flanges of the deformable bus bar to deform the deformable bus bar until one of the bus bar positive and negative terminal flanges contacts a corresponding one of the positive and negative terminals of the battery cell, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Illustrative embodiments of the disclosure will now be described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of an exemplary deformable busbar; Fig. 2 is a front view of an illustrative embodiment of a deformable busbar assembly having the Fig. 1 illustrated exemplary deformable busbar; Fig. 3 is a front view of the illustrative deformable busbar assembly clamped onto a positive terminal and a negative terminal of a battery cell, wherein an electrode gap initially exists between the negative terminal and the deformable busbar due to a height difference between the positive terminal and the negative terminal upon installation of the deformable busbar; Fig. 4 is a front view of an illustrative deformable busbar assembly with the deformable busbar deformed to accommodate the height difference between the positive and negative terminals; and Fig. 5 is a flowchart of an illustrative embodiment of a method of installing a deformable busbar. DETAILED DESCRIPTION

[0009] The following detailed description is merely exemplary in nature and is not intended to limit the described embodiments or the application and uses of the described embodiments. As used herein, the word "exemplary" or "illustrative" means "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" or "illustrative" is not necessarily to be construed as preferred or advantageous over other implementations. All implementations described below are exemplary implementations presented to enable one skilled in the art to practice the disclosure, and are not intended to limit the scope of the claims.Furthermore, the illustrative embodiments described herein are not exhaustive, and embodiments or implementations other than those described herein that fall within the scope of the appended claims are possible. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the foregoing technical field, general background art, brief summary, or the following detailed description.

[0010] With initial reference to the Fig. 1 and Fig. 2 shows an exemplary deformable busbar 1 ( Fig. 1), which is for an illustrative embodiment of a deformable busbar assembly 10 ( Fig. 2). The deformable busbar 1 may comprise any suitable flexible or deformable and current-conducting material. The deformable busbar 1 may comprise a busbar body 2. In some embodiments, the busbar body 2 may be generally elongated and rectangular, having a pair of parallel longitudinal body edges 2a, 2b, respectively, and transverse body edges 2c extending between the longitudinal body edges 2a, 2b. A busbar positive terminal flange 3 and a busbar negative terminal flange 4 extend in spaced-apart relationship along the longitudinal body edge 2b from the busbar body 2. A busbar slot 5 may extend between the busbar positive terminal flange 3 and the busbar negative terminal flange 4.A flange connecting portion 6 can connect the busbar positive pole flange 3 and the busbar negative pole flange 4 between the busbar slot 5 and the busbar body 2.

[0011] As in Fig. 2, in an exemplary application described below, the deformable busbar 1 may be included as part of the deformable busbar assembly 10. The deformable busbar assembly 10 may include a deformable busbar frame 11, which may be made of plastic or another deformable material. The busbar frame 11 may include a busbar frame positive terminal flange 12 and a busbar frame negative terminal flange 13. A busbar frame flange connector 14 may connect the busbar frame positive terminal flange 12 and the busbar frame negative terminal flange 13. A busbar flange slot 15 may separate the busbar frame positive terminal flange 12 and the busbar frame negative terminal flange 13 at the busbar frame flange connector 14.Accordingly, the busbar frame positive pole flange 12 and the busbar frame negative pole flange 13 of the busbar frame 11 can rest on the busbar positive pole flange 3 and the busbar negative pole flange 4 of the deformable busbar 1, respectively, wherein the busbar slot 5 of the deformable busbar 1 matches the busbar frame flange slot 15 of the busbar frame 11.

[0012] Next, with reference to Fig. 3 and Fig. 4, in an exemplary application of the deformable bus bar 1, the deformable bus bar assembly 10 is placed on a battery cell 18 of an HV vehicle. The battery cell 18 may be a conventional battery cell used to provide a source of electrical power to an EV (Electric Vehicle). The battery cell 18 may have a positive terminal 20 and a negative terminal 22 that are offset from each other or different in height. The bus bar positive terminal flange 3 of the deformable bus bar 1 engages the positive terminal 20 of the battery cell 18. However, due to the height difference between the positive terminal 20 and the negative terminal 22 of the battery cell 18, a contact gap 32 exists between the bus bar negative terminal flange 4 of the deformable bus bar 1 and the negative terminal 22 of the battery cell 18.A positive terminal clamp finger 26 and a negative terminal clamp finger 28 may secure the deformable busbar assembly 10 to the positive terminal 20 and the negative terminal 22 of the battery cell 18, as will be understood by one skilled in the art.

[0013] As in Fig. 4, the negative pole clamping finger 28 is tightened to increasingly deform the busbar frame negative pole flange 13 at the busbar frame flange connector 14 of the busbar frame 11 and the underlying busbar negative pole flange 4 at the busbar slot 5 and flange connection portion 6 of the deformable busbar 1. Thus, the busbar negative pole flange 4 and the busbar frame negative pole flange 13 cross the contact gap 32 ( Fig. 3) until the busbar negative terminal flange 4 makes firm contact or engagement with the negative terminal 22 of the battery cell 18. The busbar positive terminal flange 3 and the busbar negative terminal flange 4 can then be welded to the positive terminal 20 and the negative terminal 22, respectively.

[0014] Those skilled in the art will understand that the deformable busbar 1 can be deformed to compensate for the height difference between adjacent terminals on a battery cell in response to the application of pressure to the deformable busbar. Compared to conventional busbars, the deformable busbar can result in a significant reduction or elimination of a contact gap between the busbar and the positive or negative terminal on a battery cell. Because the deformable busbar requires significantly less clamping force to be applied for deformation to reduce or eliminate the contact gap, the total pressure necessary to be applied to the battery array or pack during the welding operation is substantially reduced. This expedient can reduce the risk of damaging the battery array or pack due to overload forces.Additionally, the flexibility of this busbar reduces any peel or shear forces that may occur at the weld points due to any post-weld cell movement. These movements can be caused by handling the battery cell array after the assembly is welded into the battery pack and during the battery pack's lifetime in the vehicle.

[0015] Next, with reference to Fig.5 shows a flowchart 500 of an illustrative embodiment of a deformable busbar installation method. At block 102, a busbar positive terminal flange and a busbar negative terminal flange of a deformable busbar are placed on a positive and negative terminal of a battery cell, respectively. A busbar slot extends between the busbar positive terminal flange and the busbar negative terminal flange. A contact gap exists between the busbar positive terminal flange and the positive terminal and the busbar negative terminal flange and the negative terminal.

[0016] At block 104, pressure is applied against the positive busbar terminal flange or the negative busbar terminal flange of the deformable busbar. In some embodiments, a busbar frame may be placed on the deformable busbar, and pressure may be applied to the busbar frame. The deformable busbar deforms at the busbar slot until the positive busbar terminal flange or the negative busbar terminal flange crosses the contact gap and makes firm contact with the corresponding positive or negative terminal. At block 106, the positive busbar terminal flange and the negative busbar terminal flange of the deformable busbar may be welded to the positive or negative terminal of the battery cell, respectively.

[0017] While the embodiments of the disclosure have been described with reference to particular embodiments, it is to be understood that the specific embodiments are for purposes of illustration and not limitation, since other variations will become apparent to those skilled in the art.

Claims

[1] Busbar assembly (10) comprising: a deformable busbar (1) with a busbar slot (5) separating a busbar positive pole flange (3) and a busbar negative pole flange (4), whereby the two flanges (3, 4) can move independently of each other, the busbar assembly (10) further comprising a deformable busbar frame (11) with a busbar frame flange connector (14) connecting a busbar frame positive pole flange (12) and a busbar frame negative pole flange (13) of the busbar frame (11), characterized by , that the busbar assembly (10) further comprises a busbar frame flange slot (15) separating the busbar frame positive pole flange (12) and the busbar frame negative pole flange (13) at the busbar frame flange connector (14) of the busbar frame (11). [2] The busbar assembly (10) of claim 1, further comprising a busbar body (2), and wherein the busbar positive pole flange (3) and the busbar negative pole flange (4) extend from the busbar body (2). [3] Busbar assembly (10) according to claim 2, wherein the busbar body (2) is generally elongated. [4] The busbar assembly (10) of claim 3, wherein the busbar body (2) comprises a pair of longitudinal body edges (2a, 2b) and a pair of transverse body edges (2c), and the busbar positive pole flange (3) and the busbar negative pole flange (4) extend from the busbar body (2) along one of the longitudinal body edges (2a, 2b). [5] Busbar assembly (10) according to claim 2, wherein the busbar body (2) is generally rectangular. [6] Busbar assembly (10) according to claim 1, wherein the busbar frame (11) is made of plastic. [7] Busbar assembly (10) according to claim 1, wherein the deformable busbar (1) contains a flexible or deformable and electrically conductive material. [8] Busbar assembly (10) comprising: a deformable busbar (1) containing: - a busbar positive pole flange (4); - a busbar negative pole flange (3) spaced from the busbar positive pole flange (4); and - a busbar slot (5) separating the busbar positive pole flange (4) and the busbar negative pole flange (3); and a deformable busbar frame (11) containing: - a busbar frame positive pole flange (12) supported by the busbar positive pole flange (4) of the deformable busbar (1); and - a busbar frame negative pole flange (13) supported by the busbar negative pole flange (4) of the deformable busbar (1); characterized by , that the deformable busbar (1) includes a flange connection portion (6) connecting the busbar positive pole flange (4) and the busbar negative pole flange (3), wherein the busbar slot (5) separates the busbar positive pole flange (4) and the busbar negative pole flange (3) at the flange connection portion (6). [9] The busbar assembly of claim 8, further comprising a busbar frame flange connector (14) connecting the busbar frame positive pole flange (12) and the busbar frame negative pole flange (13) of the busbar frame (11). [10] The busbar assembly (10) of claim 9, further comprising a busbar frame flange slot (15) separating the busbar frame positive pole flange (12) and the busbar frame negative pole flange (13) at the busbar frame flange connector (14) of the busbar frame (11). [11] The busbar assembly (10) of claim 8, further comprising a busbar body (2), and wherein the busbar positive pole flange (3) and the busbar negative pole flange (4) extend from the busbar body (2). [12] Busbar assembly (10) according to claim 11, wherein the busbar body (2) is generally elongated. [13] The busbar assembly (10) of claim 12, wherein the busbar body (2) comprises a pair of longitudinal body edges (2a, 2b) and a pair of transverse body edges (2c), and the busbar positive pole flange (3) and the busbar negative pole flange (4) extend from the busbar body (2) along one of the longitudinal body edges (2a, 2b). [14] Busbar assembly (10) according to claim 11, wherein the busbar body (2) is generally rectangular. [15] Busbar assembly (10) according to claim 8, wherein the busbar frame (11) is made of plastic. [16] Busbar assembly (10) according to claim 8, wherein the deformable busbar (1) contains a flexible or deformable and current-conducting material.

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