Battery cell and battery pack

Abstract

According to the novel battery unit and the battery pack, size bumps caused by welding between the lead and the guide plate can be avoided, so that the size of the battery unit is stabilized, and the overall size of the battery pack is easy to meet engineering management requirements. A battery cell (100) is provided with: a battery main body (110) having an electrode terminal (111) on an end surface in a first direction; a guide plate (120) fixed to the electrode terminal (111) of the battery main body (110); and the lead (130) is welded to the guide plate (120) through resistance spot welding, and the size of a welding area (140) of the resistance spot welding extending towards the outside of the battery main body (110) does not exceed the size of the lead (130) extending out of the battery main body (110) in the extending direction.

Description

Technical Field

[0001] The utility model relates to a battery unit and a battery pack. Background Art

[0002] As electronic products develop, the requirements for battery packs and circuit devices that serve as power sources for driving these electronic products continue to increase, and various studies have been conducted on their performance such as safety, battery connection structure, and production processes such as production efficiency.

[0003] Among them, in the prior art, a terminal connecting piece is provided, one end of the terminal connecting piece is welded to the electrode terminal of the single cell, and the other end of the terminal connecting piece is soldered to the wire harness, so that the electrode terminal of the single cell is electrically connected to the wire harness.

[0004] Figure 4 FIG. 2 is a schematic diagram schematically showing the technical problems existing in soldering in the prior art. Figure 4 As shown in the figure, since the wire is soldered to the guide plate as the terminal connection piece, the height of the solder package is difficult to control during soldering, which easily causes the overall height of the solder to exceed the surface of the wire insulation, resulting in a larger overall height or width of the battery pack composed of multiple single cells. In addition, since the height of the solder package is difficult to control, the size of each single cell is unstable and the tolerance is large, which makes it impossible to meet the engineering management requirements, thereby causing the overall quality of the battery pack to decline.

[0005] In addition, since soldering is performed between the wire and the guide plate serving as the terminal connecting piece, flux such as rosin used during soldering is prone to overflow, causing the flux to overflow into the connection area between the electrode terminal and the guide plate, thereby causing poor connection between the electrode terminal and the guide plate or poor spot welding. Utility Model Content

[0006] In view of the above situation, the inventor of the utility model conducted intensive research and proposed a new type of battery cell and battery pack, which can avoid the size bumps caused by welding between the wires and the guide plates, stabilize the size of the battery cell, and make the overall size of the battery pack easy to meet engineering management requirements.

[0007] The technical solution of the utility model is as follows.

[0008] The utility model provides a battery unit, characterized in that it comprises: a battery body, whose end face in a first direction has an electrode terminal; a guide plate, fixed to the electrode terminal of the battery body; and a wire, welded to the guide plate by resistance spot welding, wherein the dimension of the welding area of ​​the resistance spot welding extending to the outside of the battery body does not exceed the dimension of the wire exceeding the battery body in the direction of the extension.

[0009] Preferably, the wire includes an insulating sheath and a bare wire core, the bare wire core is welded to the guide plate by resistance spot welding, and the thickness of the welded bare wire core and the guide plate at the welding area does not exceed the cross-sectional diameter of the wire wrapped with the insulating sheath.

[0010] Preferably, the guide plate is sheet-shaped and connected to the electrode terminal in a manner orthogonal to the first direction, the wire is arranged parallel to the guide plate, and the welding area is located on the end surface of the battery body, and the dimension of the battery cell in the first direction at the welding area does not exceed the overall dimension of the battery cell in the first direction.

[0011] Preferably, the welding area is located at a position where the electrode terminal is located on the end surface of the battery body in the first direction, so that the wire is welded to the electrode terminal through the guide plate by the resistance spot welding.

[0012] Preferably, the guide plate is resistance spot welded to the electrode terminal, and the welding region is located at a position different from the electrode terminal on the end surface of the battery body in the first direction.

[0013] Preferably, the guide plate is an L-shaped sheet having a first surface connected to the electrode terminal in a manner orthogonal to the first direction, and a second surface orthogonal to the first surface, the wire is arranged parallel to the second surface, the second surface is arranged on the side of the battery body orthogonal to the end surface, and the welding area is located on the side of the battery body, and the dimension of the battery cell in the second direction orthogonal to the first direction at the welding area does not exceed the overall dimension of the battery cell in the second direction.

[0014] Preferably, the first surface of the guide plate is resistance spot welded to the electrode terminal.

[0015] Preferably, there are a plurality of the conductive wires arranged in parallel, and each of the plurality of conductive wires is welded to the guide plate by resistance spot welding.

[0016] In addition, the utility model provides a battery pack, comprising a plurality of the battery cells, wherein the plurality of the battery cells are arranged in parallel in the first direction and / or in a second direction orthogonal to the first direction.

[0017] Therefore, according to the battery cell and battery pack of the present invention, the size bumps caused by the welding between the wire and the guide plate can be avoided, the size of the battery cell is stabilized, and the overall size of the battery pack is easy to meet the engineering management requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a plan view schematically showing a battery unit 100 according to one embodiment of the present invention.

[0019] Figure 2 This is a plan view schematically showing an enlarged resistance spot welding region 140 of a battery cell 100 according to an embodiment of the present invention.

[0020] Figure 3 It is a plan view schematically showing a battery unit 200 according to another embodiment of the present invention.

[0021] Figure 4 The diagram schematically shows the technical problems existing in soldering in the prior art. DETAILED DESCRIPTION

[0022] Hereinafter, the embodiments of the present invention will be described using the accompanying drawings. However, in the embodiments described below, various technically preferred limitations are added for the implementation of the present invention. Therefore, the scope of the technology disclosed herein is not limited to the following embodiments and illustrated examples. Furthermore, the sizes, shapes, and proportional relationships in the illustrated examples are only for illustration, and are not specific sizes, shapes, and proportional relationships. In addition, in the accompanying drawings, the same symbols are used for the common structures in the embodiments, and repeated descriptions are omitted.

[0023] Figure 1 FIG. 1 is a plan view schematically showing a battery cell 100 according to an embodiment of the present invention. Figure 1 As shown, the battery cell 100 includes a battery body 110 , a lead plate 120 , and a lead wire 130 .

[0024] The battery body 110 is a single battery such as a cylindrical battery or a square battery, and can be a primary battery or a secondary battery. The secondary battery is preferably a lithium-ion secondary battery, a nickel-hydrogen secondary battery, or other secondary batteries. The battery body 110 has electrode terminals 111 as positive or negative terminals at both ends of the upper and lower directions (an example of the first direction) on the paper.

[0025] The guide plate 120 is fixed to the electrode terminal 111 of the battery body 110 and functions as a terminal connection piece. The guide plate 120 is preferably a metal sheet, and is preferably made of nickel, nickel-plated iron, or stainless steel in view of the conductivity of the guide plate 120 and the connection strength with the electrode terminal 111. The guide plate 120 is fixed to the electrode terminal 111 by spot welding such as resistance spot welding, but the guide plate 120 may also be provided with a through hole and fixed to the electrode terminal 111 as a pole by a terminal connection method such as a threaded connection. Figure 1As shown, the guide plate 120 is fixed above the electrode terminal 111 in parallel with the end surface of the battery body 110 where the electrode terminal 111 is located (ie, on a plane perpendicular to the vertical direction of the paper).

[0026] The wire 130 includes a bare wire core 132 and an insulating sheath 131 covering the bare wire core 132, wherein the bare wire core 132 at one end of the wire 130 is welded to the guide plate 120 at a welding area 140 by resistance spot welding. The other end of the wire 130 is connected to, for example, other electrode terminals or external components (not shown), and the external components may be temperature protection components such as temperature fuses, PTCs, thermal switches, etc.

[0027] The battery cell 100 is, for example, a battery cell used in a battery pack composed of a plurality of battery cells 100 connected in series and / or in parallel. The battery pack is composed of a plurality of battery cells 100 arranged in parallel in a first direction (up and down direction on the paper) and / or in a second direction orthogonal to the first direction. In addition, the battery pack is soft-packed by a heat shrink tubing, or the battery pack is hard-packed by a shell, to complete the packaging of the product consisting of the battery pack. Due to the requirements for product size, it is necessary to avoid the presence of size bumps in each battery cell 100 in the battery pack as much as possible so that the overall size of the battery pack matches the assembly size of, for example, the shell packaging body. In addition, in the case of soft packing the battery pack, if there are size bumps in each battery cell 100, the bumps are also likely to cause damage to the soft pack sleeve, and are not conducive to the miniaturization of the overall product. Therefore, the utility model is committed to avoiding the presence of size bumps in each battery cell 100 in the battery pack.

[0028] Figure 2 FIG. 1 is a plan view schematically showing an enlarged resistance spot welding area 140 of a battery cell 100 according to an embodiment of the present invention. Figure 2 As shown, the bare wire core 132 and the guide plate 120 are resistance spot welded in the welding area 140. In the resistance spot welding, the welding area 140 is pressurized by a spot welding machine, and a current is passed through the welding area 140 to melt the bare wire core 132 and the guide plate 120. Since the resistance spot welding does not use solder wire, unlike solder welding, there will be no solder bumps caused by the melting of the solder wire. Figure 1 As shown, the resistance spot welding welding area 140 is toward the outside of the battery body 110 ( Figure 1 The extended dimension (in the figure is the upper side on the paper) does not exceed the dimension of the wire 120 exceeding the battery body 110 in the extending direction.

[0029] Specifically, the thickness of the bare wire core 132 and the guide plate 120 at the welding area 140 does not exceed the cross-sectional diameter of the wire 130 wrapped with the insulation skin 131. In other words, the height of the welding area 140 does not exceed the height of the insulation skin 131 of the wire 120. Figure 1 As shown, the size of the battery cell 100 in the first direction at the welding area 140 does not exceed the overall size L of the battery cell 100 in the first direction. Therefore, the overall size L of the battery cell 100 in the first direction is limited only by the diameter of the wire 130, and is not limited by the height of the welding area 140. Therefore, it is easy to manufacture a battery cell 100 with a stable overall size L in the first direction, and the battery cell 100 is not prone to size bumps.

[0030] In addition, the position of the welding area 140 of the resistance spot welding is not limited. The welding area 140 can be located at the position of the electrode terminal 111 on the end surface of the battery body 110 where the electrode terminal 111 is located, so that the wire 130 is welded to the electrode terminal 111 via the guide plate 120 through the resistance spot welding; or the welding area 140 can be located at a position different from the electrode terminal 111 on the end surface where the electrode terminal 111 of the battery body is located, so that the guide plate 120 is welded to the electrode terminal 111 through one resistance spot welding, and then the wire 130 is welded to the guide plate 120 through another resistance spot welding.

[0031] Figure 3 This is a plan view schematically showing a battery cell 200 according to another embodiment of the present invention. The differences between the battery cell 200 and the battery cell 100 will be described below, and the description of the overlapping contents will be omitted.

[0032] like Figure 3 As shown, the battery cell 200 is different from the battery cell 100 in that it has a guide plate 220. The guide plate 220 is an L-shaped guide plate, having a first surface 221 connected to the electrode terminal 111 of the battery body 110 in parallel with the end surface where the electrode terminal 111 is located (that is, orthogonal to the first direction), and a second surface 222 orthogonal to the first surface 221 via a bent portion. The second surface 222 is arranged on the side surface of the battery body 110 orthogonal to the end surface where the electrode terminal 111 is located, and the lead 120 is arranged on the side surface parallel to the second surface 222 and is welded to the second surface 222 of the guide plate 220 by resistance spot welding. As shown Figure 3 As shown, the resistance spot welding welding area 140 is toward the outside of the battery body 110 ( Figure 3 The extended dimension (left side of the paper) does not exceed the dimension of the wire 120 exceeding the battery body 110 in the extending direction.

[0033] Thus, if Figure 3As shown, the size of the battery cell 100 in the second direction (left-right direction of the paper) at the welding area 140 does not exceed the overall size W of the battery cell 100 in the second direction. Therefore, the overall size W of the battery cell 100 in the second direction is limited only by the diameter of the wire 130, and is not limited by the height of the welding area 140. Therefore, it is easy to manufacture a battery cell 100 with a stable overall size W in the second direction, and the battery cell 100 is not prone to size bumps.

[0034] In addition, in the battery cell 100, a plurality of wires 130 may be arranged in parallel, and each of the plurality of wires 130 is welded to the guide plate 120 at the welding area 140 by resistance spot welding. Thus, even if there is a need to weld a plurality of wires 120, the overall size of the battery cell 100 will not be enlarged due to welding a plurality of wires 120, and the battery cell 100 is not prone to size bumps.

[0035] Thus, by combining multiple Figure 1 or Figure 3 The battery cells 100 and 200 shown are arranged in parallel in a first direction (up and down direction on the paper) and / or in a second direction orthogonal to the first direction to form a battery pack, which can ensure that the overall size of the battery pack is stable and miniaturized and is less likely to have size bumps.

[0036] The present invention can be omitted, replaced, and modified in various ways without departing from the gist of the invention. These embodiments and their modifications are all within the scope or gist of the invention, and are also within the scope of the invention described in the claims and their equivalents.

Claims

1. A battery cell, characterized in that: have: A battery body, whose end surface in the first direction has an electrode terminal; A guide plate fixed to the electrode terminal of the battery body; and The wire is welded to the guide plate by resistance spot welding, The dimension of the resistance spot welding welding area extending toward the outside of the battery body does not exceed the dimension of the wire extending beyond the battery body in the extending direction.

2. The battery cell according to claim 1, wherein: The conductor includes an insulating sheath and a bare wire core, and the bare wire core is welded to the guide plate by resistance spot welding. The thickness of the welded bare wire core and the guide plate at the welding area does not exceed the cross-sectional diameter of the wire wrapped with the insulation sheath.

3. The battery cell according to claim 2, characterized in that The guide plate is in sheet form and connected to the electrode terminal in a manner orthogonal to the first direction, the lead wire is arranged parallel to the guide plate, and the welding area is located on the end surface of the battery body, A dimension of the battery cell in the first direction at the welding region does not exceed an overall dimension of the battery cell in the first direction.

4. The battery cell according to claim 3, characterized in that The welding region is located at a position where the electrode terminal is located on the end surface of the battery body in the first direction, so that the lead wire is welded to the electrode terminal through the guide plate by the resistance spot welding.

5. The battery cell according to claim 3, wherein: The guide plate is resistance spot welded to the electrode terminal, The welding region is located at a position different from the electrode terminal on the end surface of the battery body in the first direction.

6. The battery cell according to claim 2, characterized in that The guide plate is an L-shaped sheet having a first surface connected to the electrode terminal in a manner perpendicular to the first direction and a second surface perpendicular to the first surface, and the lead is arranged parallel to the second surface. The second surface is arranged on a side surface of the battery body that is orthogonal to the end surface, and the welding area is located on the side surface of the battery body. A dimension of the battery cell in a second direction orthogonal to the first direction at the welding region does not exceed an overall dimension of the battery cell in the second direction.

7. The battery cell according to claim 6, wherein: The first surface of the guide plate is resistance spot welded to the electrode terminal.

8. The battery cell according to any one of claims 1 to 7, wherein: having a plurality of said conductors arranged in parallel, The plurality of conductive wires are each welded to the guide plate by resistance spot welding.

9. A battery pack, characterized in that: A device comprising a plurality of battery cells according to any one of claims 1 to 8, The plurality of battery cells are arranged in parallel in the first direction and / or a second direction orthogonal to the first direction.

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