Battery module and battery pack

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery module and a battery pack, the battery module comprises a battery cell group, a pre-tightening force adjusting assembly and end plates, the battery cell group comprises a plurality of battery cells which are sequentially arranged along a first direction, the end plates are arranged at two ends of the battery cell group along the first direction, the pre-tightening force adjusting assembly comprises an elastic piece, and the elastic piece is connected with the pre-tightening force adjusting assembly. The two ends of the elastic piece are connected with the end plates at the two ends of the battery cell group respectively, the elastic piece is in a stretched state, and when the size of one or more battery cells in the battery cell group deviates in the first direction, the two end plates can still be matched with each other to clamp the battery cell group, so that the problem that the battery cells are loosened and even fall off from the battery cell group is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery module and a battery pack. Background Art

[0002] An existing battery module usually includes a plurality of battery cells and two end plates. When assembling the battery module, the plurality of battery cells are arranged in sequence, and an insulating gasket is sandwiched between two adjacent battery cells to form a battery cell group. The two end plates are respectively arranged at both ends of the battery cell group, and then the battery cell group and the two end plates are tied together with a steel belt.

[0003] However, due to the thickness deviation of the battery cells, the steel belt may not be tied tightly, which may cause the battery cells to loosen or even fall from the battery pack.

[0004] Therefore, there is an urgent need to propose a battery module and a battery pack to solve the above technical problems. Utility Model Content

[0005] The first object of the utility model is to provide a battery module. When there is a deviation in the size of one or more battery cells in a battery cell group in a first direction, two end plates can still cooperate with each other to clamp the battery cell group to avoid the problem of the battery cells loosening or even falling from the battery cell group.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] Battery module, including:

[0008] A battery cell group, the battery cell group comprising a plurality of battery cells arranged in sequence along a first direction;

[0009] End plates, both ends of the battery cell group are provided with end plates along the first direction;

[0010] The preload force adjustment component includes an elastic member, two ends of the elastic member are respectively connected to the end plates at the two ends of the battery cell group, and the elastic member is in a stretched state.

[0011] Optionally, the preload force adjustment assembly further includes an adjustment rod and a locking structure, the adjustment rod includes a first end and a second end, the first end is connected to the end of the elastic member, and the second end is connected to the end plate via the locking structure.

[0012] Optionally, the locking structure includes a nut and an external thread arranged on the second end, the second end is movably arranged through the end plate, and the nut is screwed on a portion of the second end extending out of the end plate;

[0013] Or, the locking structure includes a threaded hole provided on the end plate and an external thread provided on the second end, the threaded hole and the external thread thread cooperating with each other;

[0014] Alternatively, the locking structure includes a pin, a socket opened on the side wall of the end plate, and a plurality of slots opened at the second end, the plurality of slots are arranged at intervals along the axial direction of the adjusting rod, the second end is movably penetrated through the end plate, the pin is detachably penetrated through the socket and detachably inserted into the slot.

[0015] Optionally, both ends of the elastic member are correspondingly connected with adjustment rods, and each adjustment rod corresponds to a locking structure.

[0016] Optionally, the end portion of the elastic member is detachably connected to the first end.

[0017] Optionally, one of the end portion and the first end of the elastic member is provided with a hook, and the other is provided with a through hole, and the hook is passed through the through hole.

[0018] Optionally, the hook is U-shaped.

[0019] Optionally, a connecting ear is protruding from the side wall of the end plate, and the second end is movably inserted into the connecting ear.

[0020] Optionally, at least two groups of preload adjustment components are provided on both sides of the battery cell group along the first direction, and the at least two groups of preload adjustment components on each side are arranged at intervals along the height direction of the battery cell group.

[0021] A second object of the present invention is to provide a battery pack that can significantly reduce the probability of a battery cell becoming loose or even falling out of the battery cell group.

[0022] To achieve this purpose, the utility model adopts the following technical solutions:

[0023] The battery pack comprises a battery box and the above-mentioned battery module, wherein the battery module is installed in the battery box.

[0024] Beneficial effects:

[0025] In the battery module provided by the utility model, the two ends of the elastic member are respectively connected to the end plates at the two ends of the battery cell group, and the elastic member is in a stretched state, so that the two end plates can cooperate with each other to clamp the battery cell group under the influence of the rebound force of the elastic member. When there is a deviation in the size of one or more battery cells in the battery cell group in the first direction, the size of the battery cell group in the first direction will also deviate. Since the elastic member is elastic, its stretching amount can change with the change in the size of the battery cell group in the first direction. Therefore, the elastic member can still apply a rebound force to the two end plates, so that the two end plates can cooperate with each other to clamp the battery cell group under the influence of the rebound force, thereby avoiding the problem of the battery cells loosening or even falling from the battery cell group due to the size deviation of the battery cells in the first direction.

[0026] The battery pack provided by the utility model adopts the above-mentioned battery module. When there is a dimensional deviation of the battery cell in the first direction, the two end plates can still apply a clamping force to the battery cell group under the action of the elastic member, which greatly reduces the probability of the battery cell loosening or even falling from the battery cell group. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of a battery module provided by an embodiment of the utility model;

[0028] Figure 2 yes Figure 1 A partial enlarged view of the middle A;

[0029] Figure 3 yes Figure 1 A partial enlarged view of point B in the middle.

[0030] In the figure:

[0031] 100, battery cell group; 110, battery cell; 200, end plate; 210, connecting ear; 310, elastic member; 311, hook; 320, adjustment rod; 321, first end; 322, second end; 330, nut. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0036] This embodiment provides a battery module. When one or more battery cells in a battery cell group have size deviations in a first direction, the two end plates can still cooperate with each other to clamp the battery cell group, thereby preventing the battery cells from loosening or even falling from the battery cell group.

[0037] Specifically, Figure 1 As shown, the battery module includes a battery cell group 100, a preload adjustment component and an end plate 200, wherein the battery cell group 100 includes a plurality of Figure 1 The battery cells 110 are arranged in sequence along the x direction in the embodiment, and in the present embodiment, the first direction is the thickness direction of the battery cells 110. Along the first direction, end plates 200 are provided at both ends of the battery cell group 100. The preload force adjustment component includes an elastic member 310. Both ends of the elastic member 310 are respectively connected to the two end plates 200, and the elastic member 310 is in a stretched state.

[0038] Based on the above design, the two ends of the elastic member 310 are respectively connected to the end plates 200 at the two ends of the battery cell group 100, and the elastic member 310 is in a stretched state, so that the two end plates 200 can cooperate with each other to clamp the battery cell group 100 under the influence of the rebound force of the elastic member 310. When there is a deviation in the size of one or more battery cells 110 in the battery cell group 100 in the first direction, the size of the battery cell group 100 in the first direction will also deviate. Since the elastic member 310 is elastic, its stretching amount can change with the change in the size of the battery cell group 100 in the first direction. Therefore, the elastic member 310 can still apply a rebound force to the two end plates 200. Under the influence of the rebound force, the two end plates 200 cooperate with each other to clamp the battery cell group 100, thereby avoiding the problem of the battery cell 110 loosening or even falling from the battery cell group 100 due to the size deviation of the battery cell 110 in the first direction.

[0039] On the other hand, during the charge and discharge process of the battery module, the thickness of the battery cell 110 will change, and then the thickness of the battery cell group 100 will also change. During this process, the stretching amount of the elastic member 310 can change with the change in the thickness of the battery cell group 100, so that the elastic member 310 can always apply a rebound force to the two end plates 200. Under the action of the elastic member 310, the two end plates 200 can always cooperate with each other to clamp the battery cell group 100. It can be seen that the setting of the elastic member 310 realizes the adaptive adjustment of the clamping force of the battery cell group 100 during the charge and discharge process, so that the battery cell 110 is always in a clamped state.

[0040] Optionally, an insulating gasket (not shown in the figure) is sandwiched between each two adjacent battery cells 110 to insulate the two adjacent battery cells 110. In actual production, the insulating gasket also has the problem of size deviation. When the thickness of the insulating gasket has deviation (when the size in the x direction changes), the stretching amount of the elastic member 310 will also change accordingly, and then the elastic member 310 can still apply a rebound force to the two end plates 200, so that the battery cell group 100 can still be clamped between the two end plates 200.

[0041] Optionally, the elastic member 310 is a tension spring. Of course, in other embodiments, the elastic member 310 may also be other elastic elements such as rubber.

[0042] Alternatively, if Figures 1 to 3 As shown, the preload adjustment assembly also includes an adjustment rod 320 and a locking structure. The adjustment rod 320 includes a first end 321 and a second end 322. The first end 321 is connected to the end of the elastic member 310, and the second end 322 is connected to the end plate 200 through the locking structure. The design of the adjustment rod 320 extends the distance between the end of the elastic member 310 and the end plate 200, thereby increasing the number of battery cells 110 in the battery cell group 100 to adapt to high-capacity battery modules.

[0043] Alternatively, if Figures 1 to 3 As shown, both ends of the elastic member 310 are connected to corresponding adjustment rods 320, and each adjustment rod 320 corresponds to a locking structure to increase the number of battery cells 110 distributed at both ends of the elastic member 310, further improving the power of the battery module.

[0044] Alternatively, if Figures 1 to 3 As shown, the locking structure includes a nut 330 and an external thread arranged at the second end 322. The second end 322 is movably penetrated in the end plate 200 along the first direction. The nut 330 is located on the side of the end plate 200 away from the elastic member 310, and the nut 330 is screwed on the portion of the second end 322 extending out of the end plate 200 to achieve the connection between the second end 322 and the end plate 200. The structural design is simple, which is conducive to reducing the difficulty of assembling the adjustment rod 320 and the end plate 200. In addition, when it is necessary to adjust the clamping force applied by the end plate 200 to the battery cell group 100, the nut 330 is loosened, and the adjustment rod 320 is pushed and pulled to move the adjustment rod 320 in the first direction relative to the end plate 200. The stretching amount of the elastic member 310 will change with the movement of the adjustment rod 320, thereby changing the rebound force of the elastic member 310. After the adjustment rod 320 is moved to a suitable position (i.e., after the clamping force is adjusted to a suitable size), the nut 330 is tightened to lock the second end 322, thereby completing the adjustment of the clamping force of the battery cell group 100 to meet the clamping force requirements of different battery cell groups 100. In this embodiment, the adjustment rod 320 is a long screw, and of course it can also be other rod-shaped structures with external threads.

[0045] In one embodiment, the locking structure includes a threaded hole opened on the end plate 200 and an external thread set on the second end 322. The threaded hole cooperates with the external thread to achieve the connection between the second end 322 and the end plate 200, and to adjust the clamping force of the battery cell group 100.

[0046] In another embodiment, the locking structure includes a pin, a socket opened on the side wall of the end plate 200, and a plurality of slots opened at the second end 322. The plurality of slots are arranged at intervals along the axial direction of the adjusting rod 320. The second end 322 is movably penetrated in the end plate 200 along the first direction. The pin is detachably penetrated in the socket and detachably inserted in the slot. When the adjusting rod 320 needs to be adjusted, the pin is pulled out. After the adjusting rod 320 is moved to a suitable position, the pin is passed through the socket and inserted into the slot to complete the adjustment of the clamping force of the battery cell group 100 and the connection between the second end 322 and the end plate 200.

[0047] Alternatively, if Figures 1 to 3As shown, a connecting ear 210 is protruding from the side wall of the end plate 200, and the second end 322 of the adjustment rod 320 is movably inserted into the connecting ear 210. The design of the connecting ear 210 reduces the size of the end plate 200, which has the effect of improving the energy density of the battery module.

[0048] Alternatively, if Figures 1 to 3 As shown, the end of the elastic member 310 is detachably connected to the first end 321. Further, a hook 311 is provided at the end of the elastic member 310, and a perforation is provided at the first end 321. The hook 311 is inserted into the perforation to facilitate the assembly of the elastic member 310 and the adjustment rod 320. Of course, the hook 311 can also be provided at the first end 321, and the perforation can be provided at the end of the elastic member 310. The hook 311 can also be used to achieve a detachable connection between the elastic member 310 and the first end 321 of the adjustment rod 320. It is understandable that the elastic member 310 and the first end 321 can also be detachably connected by other means such as threaded connection, which will not be listed here one by one.

[0049] Preferably, if Figures 1 to 3 As shown, the hook 311 is U-shaped. The U-shaped hook 311 can reduce the probability of the hook 311 being loosened from the through hole, thereby improving the reliability of the connection between the elastic member 310 and the first end 321 .

[0050] Alternatively, if Figures 1 to 3 As shown, at least two sets of preload adjustment components are provided on both sides of the battery cell group 100 along the first direction (i.e., Figure 1 In the y direction, at least two groups of pre-tightening force adjustment components are provided on each side of the battery cell group 100), so that both sides of the battery cell group 100 can be subjected to the compression force, and the at least two groups of pre-tightening force adjustment components on each side of the battery cell group 100 are arranged at intervals along the height direction of the battery cell group 100 to uniformly apply the compression force to the battery cell group 100 in the height direction. In the present embodiment, four groups of pre-tightening force adjustment components are provided, and the four groups of pre-tightening force adjustment components are symmetrically arranged in pairs on both sides of the battery cell group 100 to further improve the uniformity of the compression force applied to the battery cell group 100. Of course, in other implementation schemes, the pre-tightening force adjustment components can also be two, three or five groups, etc., and the pre-tightening force adjustment components located on both sides of the battery cell group 100 can be symmetrically arranged or asymmetrically arranged, which is not specifically limited here.

[0051] In the battery module provided in this embodiment, the second end 322 of the adjusting rod 320 passes through the end plate 200 and is threadedly connected to the nut 330, and the hook 311 on the elastic member 310 passes through the through hole on the first end 321 of the adjusting rod 320. Therefore, the rebound force of the elastic member 310 can be used to make the two end plates 200 cooperate to clamp the battery cell group 100, which not only reduces the probability of the battery cell 110 loosening or even falling during transportation and use of the battery module, but also reduces the difficulty of assembling the battery module, reduces the safety risk of the battery module and improves the production efficiency, and is suitable for being widely promoted and used.

[0052] It should be pointed out that the elastic member 310, the adjustment rod 320 and the nut 330 can be selected in a variety of ways. For example, in this embodiment, when selecting the tension spring, the long screw and the nut 330, the battery cell group 100 can be first tied with a steel strip, and then the pre-tightening force of the steel strip is collected to calculate the required rebound force of the tension spring; the maximum load and maximum deformation required for the tension spring are obtained according to the calculated rebound force, and then the tension spring is selected; the long screw and the nut 330 are designed according to the average value of the calculated multiple groups of rebound forces, and then the production is guided. The data collection of the pre-tightening force of the steel strip, the calculation of the rebound force of the tension spring, the calculation of the maximum load and maximum deformation of the tension spring, and the process design of the long screw and the nut 330 are all conventional technologies in the field and will not be repeated here.

[0053] This embodiment also provides a battery pack, which can significantly reduce the probability of the battery cell 110 becoming loose or even falling out of the battery cell group 100 .

[0054] Specifically, the battery pack includes a battery box and the above-mentioned battery module, and the battery module is installed in the battery box. The battery pack adopts the above-mentioned battery module. When the battery cell 110 has a size deviation in the first direction, the two end plates 200 can still apply a clamping force to the battery cell group 100 under the action of the elastic member 310, which greatly reduces the probability of the battery cell 110 loosening or even falling from the battery cell group 100.

[0055] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A battery module, characterized in that: include: A battery cell group (100), the battery cell group (100) comprising a plurality of battery cells (110) arranged in sequence along a first direction; End plates (200), both ends of the battery cell group (100) are provided with the end plates (200) along the first direction; A preload force adjustment component, the preload force adjustment component comprising an elastic member (310), two ends of the elastic member (310) are respectively connected to the end plates (200) at two ends of the battery cell group (100), and the elastic member (310) is in a stretched state.

2. The battery module according to claim 1, characterized in that: The preload force adjustment assembly also includes an adjustment rod (320) and a locking structure, wherein the adjustment rod (320) includes a first end (321) and a second end (322), wherein the first end (321) is connected to the end of the elastic member (310), and the second end (322) is connected to the end plate (200) via the locking structure.

3. The battery module according to claim 2, characterized in that: The locking structure comprises a nut (330) and an external thread arranged on the second end (322), the second end (322) is movably inserted into the end plate (200), and the nut (330) is screwed on a portion of the second end (322) extending out of the end plate (200); Alternatively, the locking structure comprises a threaded hole provided on the end plate (200) and an external thread provided on the second end (322), and the threaded hole is threadably matched with the external thread; Alternatively, the locking structure includes a pin, a socket opened on the side wall of the end plate (200), and a plurality of slots opened on the second end (322), the plurality of slots being arranged at intervals along the axial direction of the adjusting rod, the second end (322) being movably inserted into the end plate (200), and the pin being detachably inserted into the socket and detachably inserted into the slot.

4. The battery module according to claim 2, characterized in that: Both ends of the elastic member (310) are correspondingly connected to the adjustment rods (320), and each of the adjustment rods (320) corresponds to one of the locking structures.

5. The battery module according to claim 2, characterized in that: The end of the elastic member (310) is detachably connected to the first end (321).

6. The battery module according to claim 5, characterized in that: One of the end of the elastic member (310) and the first end (321) is provided with a hook (311), and the other is provided with a through hole, and the hook (311) is passed through the through hole.

7. The battery module according to claim 6, characterized in that: The hook (311) is U-shaped.

8. The battery module according to claim 2, characterized in that: A connecting ear (210) is protrudingly provided on the side wall of the end plate (200), and the second end (322) is movably inserted into the connecting ear (210).

9. The battery module according to any one of claims 1 to 8, characterized in that: At least two groups of the preload force adjustment components are arranged on both sides of the battery cell group (100) along the first direction, and the at least two groups of the preload force adjustment components on each side are arranged at intervals along the height direction of the battery cell group (100).

10. A battery pack, characterized in that: It comprises a battery box and a battery module as described in any one of claims 1 to 9, wherein the battery module is installed in the battery box.

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