Connecting piece with short-circuit protection function and battery module structure

Abstract

The utility model provides a connecting piece with a short-circuit protection function, the connecting piece is suitable for a battery module, the connecting piece comprises a first connecting part, an overcurrent part and a second connecting part, and the overcurrent part is connected with the first connecting part and the second connecting part; the over-current part comprises multiple stages of over-current bridges which are independently arranged, and each stage of over-current bridge is connected with the first connecting part and the second connecting part; and the overflowing capacities of the multiple stages of overflowing bridges are arranged in a gradient manner from the center of the overflowing part to the edge direction of the overflowing part. The embodiment of the utility model further provides a battery module structure. The connecting piece adopts a multi-stage over-current bridge design, the step-by-step fusing of the connecting piece is realized under the condition of ensuring the over-current capability, the fusing process is equivalent to the conversion of the connecting piece into a high internal resistance load, the influence on the interior of the battery cell during external short circuit can be effectively reduced, a better short-circuit protection function can be provided for the whole system, and the service life of the battery cell is prolonged. And the reliability of the whole system is effectively improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of batteries, and in particular relates to a connecting piece and a battery module structure with a short-circuit protection function. Background Art

[0002] With the rapid development of new energy in my country, electrochemical energy storage technology has been widely used in industrial and commercial energy storage, electric vehicles and other fields. As a key component of energy storage and supply, battery modules are still facing a series of challenges. Short circuit is an important factor affecting the safety performance of battery modules. When the external circuit fails, the battery module is physically damaged or operated incorrectly, it may cause the battery module to short-circuit, generating a huge current instantly; when the current generated exceeds the battery's tolerance, it will cause thermal runaway of the battery, posing a hidden danger to personal and property safety. Utility Model Content

[0003] The embodiments of the utility model provide a connecting piece and a battery module structure with a short-circuit protection function, aiming to solve the problems that a short circuit in an existing battery module easily leads to thermal runaway and causes battery fire, and there are major safety hazards.

[0004] To achieve the above-mentioned purpose, on the one hand, an embodiment of the utility model provides a connecting piece with a short-circuit protection function, which is suitable for a battery module, including a first connecting part, an overcurrent part and a second connecting part, wherein the overcurrent part is respectively connected to the first connecting part and the second connecting part; the overcurrent part includes a plurality of overcurrent bridges independently arranged from each other, and each level of the overcurrent bridge is respectively connected to the first connecting part and the second connecting part; from the center of the overcurrent part to the edge direction of the overcurrent part, the overcurrent capacity of the plurality of overcurrent bridges is arranged in a gradient.

[0005] As a preferred embodiment, the width or cross-sectional area of the multiple-stage current bridge is set in a gradient from the center of the current portion to the edge of the current portion. That is, in this application, the flow capacity of the current bridge can be achieved by adjusting the width of the current bridge or by adjusting the cross-sectional area of the current bridge.

[0006] As a preferred embodiment, the widths or cross-sectional areas of the multiple-stage current bridges increase step by step from the center of the current passage portion to the edge of the current passage portion.

[0007] As a preferred embodiment, the multiple levels of the current passing bridges are symmetrically arranged from the center of the current passing portion to the two sides of the current passing portion.

[0008] As a preferred embodiment, a gap is provided between two adjacent levels of the current bridges.

[0009] As a preferred embodiment, in the direction from the center of the current-carrying portion to the edge of the current-carrying portion, the width of the gap is set in a gradient.

[0010] As a preferred embodiment, in the direction from the center of the current-carrying portion to the edge of the current-carrying portion, the width of the gap decreases step by step.

[0011] As a preferred embodiment, in the direction from the center of the current-carrying portion to both sides of the current-carrying portion, the gaps are symmetrically arranged.

[0012] In the present application, a multi-stage current-carrying bridge is provided in the current-carrying portion of the connecting piece, and the width or cross-sectional area of the current-carrying bridge is distributed in a gradient, which can ensure the current-carrying capacity of the current-carrying bridge within the normal operating current range (that is, the current-carrying capacity of the multi-stage current-carrying bridge is adapted to the current range of the battery). When the current increases, the current-carrying bridge with a small width (i.e., narrow) or a small cross-sectional area fuses first. According to the resistance formula R = ρ*L / S, the cross-sectional area of the connecting piece decreases and the resistance increases; according to 2 Joule's law Q = I RT, the heat generated by the connecting piece increases, and the current-carrying bridges with a width gradient fuse in sequence (that is, in the order from the small-width to the large-width), thereby realizing the short-circuit protection function.

[0013] On the other hand, the embodiment of the present invention further provides a battery module structure, which includes a plurality of battery cells, and adjacent two battery cells are connected in series or in parallel through the connecting piece with a short-circuit protection function.

[0014] As a preferred embodiment, the battery module structure is a square battery module structure.

[0015] In the present application, by using a connecting piece with a short-circuit protection function to realize the series or parallel connection between the battery cells of the battery module, it can be ensured that when the battery module has a short circuit and generates a large current, the circuit can be cut off in time to avoid further danger, thereby protecting personal and property safety. At the same time, the connecting piece of the present application adopts a multi-stage current-carrying bridge design to replace the solid current-carrying connecting piece. While ensuring the current-carrying capacity, the connecting piece is gradually fused. The fusing process is equivalent to converting the connecting piece into a high-resistance load. While cutting off the module circuit, it can effectively reduce the influence on the inside of the battery cell during an external short circuit, and can provide a better short-circuit protection function for the whole system, effectively improving the reliability of the whole system, and further effectively improving the environmental adaptability of the whole battery module. Description of the Drawings

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0017] Figure 1 is a schematic structural view of a connecting piece with a short-circuit protection function according to an embodiment of the present invention;

[0018] Figure 2 is Figure 1 a schematic structural view of the connecting piece with a short-circuit protection function from another angle;

[0019] Figure 3 is a schematic structural view of a battery module structure according to another embodiment of the present invention. Detailed Embodiments

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0021] It should be noted that if there are directional indications (such as up, down, left, right, front, back, top, bottom...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0022] In this application, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. It can be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0024] In addition, if the description of "first", "second", etc. is involved in the embodiments of the present utility model, the description of "first", "second", etc. is only for descriptive purposes and cannot be construed as indicating or implying its relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0025] Specifically, on the one hand, as Figures 1 to 2 shown, the embodiment of the present utility model provides a connecting piece with a short-circuit protection function, which is applicable to a battery module and includes a first connecting portion 10, a current-carrying portion 20, and a second connecting portion 30. The current-carrying portion 20 is respectively connected to the first connecting portion 10 and the second connecting portion 30; the current-carrying portion 20 includes a plurality of mutually independent current-carrying bridges 21, and each current-carrying bridge 21 is respectively connected to the first connecting portion 10 and the second connecting portion 30; in the direction from the center of the current-carrying portion 20 to the edge of the current-carrying portion 20, the current-carrying capacities of the plurality of current-carrying bridges 21 are set in a gradient manner.

[0026] In this embodiment, the first connecting portion 10, the current-carrying portion 20, and the second connecting portion 30 are integrally formed; the first connecting portion 10 and the second connecting portion 30 are symmetrically arranged. In this way, the stability of the connection between the connecting piece and the battery unit can be ensured.

[0027] As a preferred embodiment, in the direction from the center of the current-carrying portion 20 to the edge of the current-carrying portion 20, the widths or cross-sectional areas of the plurality of current-carrying bridges 21 are set in a gradient manner. That is, in the present application, the magnitude of the current-carrying capacity of the current-carrying bridge 21 can be achieved by adjusting the width of the current-carrying bridge 21 or by adjusting the cross-sectional area of the current-carrying bridge 21. Specifically, in this embodiment, the magnitude of the current-carrying capacity of the current-carrying bridge 21 is adjusted by adjusting the width of the current-carrying bridge 21. It can be understood that in other embodiments, the magnitude of the current-carrying capacity of the current-carrying bridge 21 can also be adjusted by adjusting the cross-sectional area of the current-carrying bridge 21.

[0028] As a preferred embodiment, from the center of the current-carrying portion 20 to the edge direction of the current-carrying portion 20, the width or cross-sectional area of the multi-stage current-carrying bridges 21 increases step by step. Specifically, in this embodiment, from the center of the current-carrying portion 20 to the edge direction of the current-carrying portion 20, the width of the multi-stage current-carrying bridges 21 increases step by step. It can be understood that in other embodiments, from the center of the current-carrying portion 20 to the edge direction of the current-carrying portion 20, the cross-sectional area of the multi-stage current-carrying bridges 21 increases step by step.

[0029] As a preferred embodiment, from the center of the current-carrying portion 20 to both sides of the current-carrying portion 20, the multi-stage current-carrying bridges 21 are symmetrically arranged. Specifically, in this embodiment, from the center of the current-carrying portion 20 to both sides of the current-carrying portion 20, the multi-stage current-carrying bridges 21 are symmetrically arranged, and each side of the current-carrying bridges 21 is provided with three stages. In other embodiments, the number of stages of the current-carrying bridges can also be set according to actual use needs, for example, it can be set to four stages, or set to five stages, etc.

[0030] As a preferred embodiment, a gap 40 is provided between two adjacent stages of the current-carrying bridges 21.

[0031] As a preferred embodiment, from the center of the current-carrying portion 20 to the edge direction of the current-carrying portion 20, the width of the gap 40 is set in a gradient. In this way, the safety when the current-carrying bridge melts can be further ensured, and the safety of short-circuit protection can be realized.

[0032] As a preferred embodiment, from the center of the current-carrying portion 20 to the edge direction of the current-carrying portion 20, the width of the gap 40 decreases step by step. In this way, the safety when the current-carrying bridge melts can be further ensured, and the safety of short-circuit protection can be realized.

[0033] As a preferred embodiment, from the center of the current-carrying portion 20 to both sides of the current-carrying portion 20, the gap 40 is symmetrically arranged. Specifically, in this embodiment, from the center of the current-carrying portion 20 to both sides of the current-carrying portion 20, each side of the gap 40 is provided with two stages. In other embodiments, the number of stages of the gap can also be set according to actual use needs, for example, it can be set to three stages, or set to four stages, etc.

[0034] In this application, the current-carrying portion of the connecting piece is provided with multi-stage current-carrying bridges, and the width or cross-sectional area of the current-carrying bridges is distributed in a gradient, which can ensure the current-carrying capacity of the current-carrying bridges within the normal operating current range (that is, the current-carrying capacity of the multi-stage current-carrying bridges is set to be adapted to the current range of the battery). When the current increases, the current-carrying bridge with a small width (i.e., narrow) or a small cross-sectional area melts first. According to the resistance formula R = ρ*L / S, the cross-sectional area of the connecting piece decreases and the resistance increases; according to Joule's law Q = I 2RT, the heat generation of the connecting piece increases, and the overcurrent bridges with a width gradient are sequentially fused (i.e., in the order from the smaller width to the larger width), thereby achieving the function of short-circuit protection.

[0035] On the other hand, as Figure 2 shown, an embodiment of the present utility model further provides a battery module structure, and the battery module structure includes a plurality of battery cells 100, and series connection or parallel connection is achieved between two adjacent battery cells 100 through the connecting piece 200 with a short-circuit protection function.

[0036] Specifically, in this embodiment, series connection is achieved between two adjacent battery cells 100 through the connecting piece 200 with a short-circuit protection function; wherein, the first connecting portion of the connecting piece 200 is connected to the positive electrode column of one battery cell 100, and the second connecting portion of the connecting piece 200 is connected to the negative electrode column of another battery cell 100; or, the first connecting portion of the connecting piece 200 is connected to the negative electrode column of one battery cell 100, and the second connecting portion of the connecting piece 200 is connected to the positive electrode column of another battery cell 100.

[0037] It can be understood that in other embodiments, parallel connection can also be achieved between two adjacent battery cells 100 through the connecting piece 200 with a short-circuit protection function.

[0038] As a preferred implementation manner, the battery module structure is a square battery module structure.

[0039] In this application, series or parallel connection between the battery cells of the battery module is achieved by using a connecting piece with a short-circuit protection function, which can ensure that when a short circuit occurs in the battery module and a large current is generated, the circuit can be cut off in time to avoid further dangers, thereby protecting personal and property safety. At the same time, the connecting piece of this application adopts a multi-stage overcurrent bridge design to replace the solid overcurrent connecting piece. While ensuring the overcurrent capacity, the gradual fusing of the connecting piece is achieved. The fusing process is equivalent to converting the connecting piece into a high internal resistance load. While cutting off the module circuit, it can effectively reduce the impact on the inside of the battery cell during an external short circuit, and can provide a better short-circuit protection function for the entire system, effectively improving the reliability of the entire system, and further effectively improving the environmental adaptability of the entire battery module as a whole.

[0040] In the description of this specification, the description referring to terms such as "one embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example.

[0041] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0042] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A connecting piece with short-circuit protection function, applicable to a battery module, characterized in that, It includes a first connection part, a current-carrying part and a second connection part, and the current-carrying part is respectively connected to the first connection part and the second connection part; the current-carrying part includes multiple levels of current-carrying bridges that are independently arranged, and each level of the current-carrying bridge is respectively connected to the first connection part and the second connection part; in the direction from the center of the current-carrying part to the edge of the current-carrying part, the current-carrying capabilities of the multiple levels of current-carrying bridges are set in a gradient manner.

2. The connecting piece with short-circuit protection function according to claim 1, wherein In the direction from the center of the current-carrying part to the edge of the current-carrying part, the widths or cross-sectional areas of the multiple levels of current-carrying bridges are set in a gradient manner.

3. The connecting piece with short-circuit protection function according to claim 2, characterized in that, In the direction from the center of the current-carrying part to the edge of the current-carrying part, the widths or cross-sectional areas of the multiple levels of current-carrying bridges increase step by step.

4. The connecting piece with short-circuit protection function according to claim 1, wherein, In the direction from the center of the current-carrying part to both sides of the current-carrying part, the multiple levels of current-carrying bridges are symmetrically arranged.

5. The connecting piece with short-circuit protection function according to claim 1, wherein A gap is provided between two adjacent levels of the current-carrying bridges.

6. The connecting piece with short-circuit protection function according to claim 5, characterized in that, In the direction from the center of the current-carrying part to the edge of the current-carrying part, the widths of the gaps are set in a gradient manner.

7. The connecting piece with short-circuit protection function according to claim 5, characterized in that, In the direction from the center of the current-carrying part to the edge of the current-carrying part, the widths of the gaps decrease step by step.

8. The connecting piece with short-circuit protection function according to claim 5, characterized in that In the direction from the center of the current-carrying part to both sides of the current-carrying part, the gaps are symmetrically arranged.

9. A battery module structure, characterized in that, The battery module structure includes multiple battery cells, and series connection or parallel connection is realized between two adjacent battery cells through the connecting piece with short-circuit protection function according to any one of claims 1 to 8.

10. The battery module structure according to claim 9, wherein, The battery module structure is a square battery module structure.

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