Battery pack

Abstract

This utility model relates to the field of power battery technology, and more particularly to a battery pack. It includes: a housing, the housing comprising a lower shell; a cell stack having multiple pouch cells, the cell stack being installed within the lower shell, and the bottom side of the cell stack being connected and fixed to the bottom plate of the lower shell; and a pressure plate component, the pressure plate component including a sampling component and a pressure plate, the pressure plate being connected to the lower shell and pressing against the top side of the cell stack, the sampling component being installed on the pressure plate and connected to the cell stack for sampling. By pressing the top side of the cell stack against the pressure plate, the overall structural stability of the cell stack is improved, thereby enhancing the product performance of the battery pack. Based on this, the sampling component is integrated onto the pressure plate, allowing the pressure plate and the sampling component to be assembled simultaneously, which improves assembly efficiency and reduces costs.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to a battery pack. Background Technology

[0002] CTP (cell to pack) battery packs omit the step of forming battery modules from individual cells, and instead directly integrate the individual cells into the battery pack. This eliminates the need for structural and electrical connectors required to form battery modules, thus increasing the space available for the individual cells themselves, and is therefore widely used.

[0003] Currently, common battery cells are classified into cylindrical cells, prismatic cells, and pouch cells according to their structure. In the process of integrating individual cells into CTP battery packs, a series of problems still exist, especially for pouch cells. Because they are not resistant to external impacts and have poor assemblability, it is troublesome to directly install pouch cell stacks into the battery pack, resulting in poor overall stability of the battery pack structure. Utility Model Content

[0004] This utility model provides a battery pack to solve the technical problem of poor overall structural stability of the battery pack, thereby improving the product performance of the battery pack.

[0005] To achieve the above and other related objectives, this utility model provides a battery pack, comprising: The housing includes a lower shell; A battery cell stack having multiple pouch cells, the battery cell stack being installed inside the lower housing, and the bottom side of the battery cell stack being connected and fixed to the bottom plate of the lower housing; The pressure plate component includes a sampling assembly and a pressure plate. The pressure plate is connected to the lower housing and presses against the top side of the cell stack. The sampling assembly is mounted on the pressure plate and connected to the cell stack for sampling.

[0006] In one embodiment of the present invention, the pressure plate is connected and fixed to the side plate of the lower housing, and is adapted to press against the top side of the battery cell stack when connected to the side plate of the lower housing.

[0007] In one embodiment of the present invention, the pressure plate is bonded and fixed to the top side of the cell stack by an adhesive block, the adhesive block extending along the stacking direction of the plurality of soft-pack cells.

[0008] In one embodiment of the present invention, a first opening is provided on the pressure plate, and the sampling component includes a voltage sampling element, which is electrically connected to the battery cell stack and is mounted on the pressure plate through the first opening.

[0009] In one embodiment of the present invention, the voltage sampling device includes a flexible circuit board having a main board body and voltage sampling terminals. A portion of the main board body is located on the tab side of the battery cell stack and is electrically connected to the battery cell stack through the voltage sampling terminals. A partial bend of the main board body forms a connecting portion, which passes through the first opening and is fixedly installed on the top side of the pressure plate.

[0010] In one embodiment of the present invention, the voltage sampling device includes a flexible circuit board and an insulating connecting piece. The flexible circuit board is located on the tab side of the battery cell stack and is electrically connected to the battery cell stack for sampling. One end of the insulating connecting piece is connected to the flexible circuit board, and the other end of the insulating connecting piece passes through the first opening and is fixedly installed on the top side of the pressure plate.

[0011] In one embodiment of the present invention, the battery pack further includes an adhesive component, the pressure plate has a second opening, the sampling component includes a temperature sampling component, the temperature sampling component has a connected wire harness and a temperature sampling terminal, the temperature sampling terminal is installed in the second opening and is bonded and fixed to the top side of the cell stack for sampling, the wire harness is arranged in a limiting manner in the second opening, and the adhesive component is connected to the pressure plate and the wire harness respectively and presses against and limits the wire harness.

[0012] In one embodiment of the present invention, a third opening is provided on the pressure plate, and the sampling component includes a temperature sampling element. The temperature sampling element has a wire harness and a temperature sampling terminal. The wire harness is placed on the top side of the pressure plate, and the temperature sampling terminal connected to the wire harness passes through the third opening and is sandwiched between the pressure plate and the top side of the battery cell stack, and contacts the battery cell stack for sampling.

[0013] In one embodiment of the present invention, the housing further includes an upper cover, which is connected to the lower housing to seal the battery cell stack inside the lower housing, and the pressure plate has an exhaust hole facing the upper cover.

[0014] In one embodiment of the present invention, a portion of the pressure plate is raised in a direction away from the top side of the battery cell stack to form a raised portion. The raised portion cooperates with the top side of the battery cell stack to define an exhaust channel. The exhaust hole is disposed on the raised portion and communicates with the exhaust channel.

[0015] In one embodiment of the present invention, there are multiple raised portions, and the multiple raised portions cooperate with the top side of the cell stack to define multiple exhaust channels, and the multiple exhaust channels are distributed at intervals along the length direction of the pouch cell.

[0016] In one embodiment of the present invention, the exhaust channel extends along the stacking direction of the plurality of pouch cells, and the raised portion is provided with a plurality of exhaust holes, which are spaced apart along the extension direction of the exhaust channel.

[0017] The beneficial effects of this utility model are as follows: The battery pack proposed in this utility model uses a pressure plate to press against the top side of the cell stack, which helps to improve the overall structural stability of the cell stack and thus improve the product performance of the battery pack. Based on this, the sampling component is integrated on the pressure plate, which allows the pressure plate and the sampling component to be assembled synchronously, which helps to improve assembly efficiency and reduce costs. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] In the attached diagram: Figure 1 This is an exploded view of the battery pack provided in Embodiment 1 of this utility model; Figure 2 This is a partial structural diagram of the battery pack provided in Embodiment 1 of the present utility model; Figure 3 for Figure 2 Top view of the battery pack; Figure 4 for Figure 3 A magnified schematic diagram of part A in the middle; Figure 5 A top view of the battery pack provided in Embodiment 1 of this utility model; Figure 6 for Figure 5 Sectional view at point BB; Figure 7 for Figure 6 A magnified schematic diagram of part C in the middle; Figure 8 for Figure 6 A magnified schematic diagram of part D in the middle; Figure 9 for Figure 1 Schematic diagram of the intermediate pressure plate; Figure 10 This is an exploded view of the battery pack provided in Embodiment 2 of this utility model; Figure 11 This is a top view of a partial structure of the battery pack provided in Embodiment 2 of this utility model; Figure 12 for Figure 11 A magnified schematic diagram of part E in the middle; Figure 13 This is a top view of the battery pack provided in Embodiment 2 of this utility model; Figure 14 for Figure 13 Sectional view at FF; Figure 15 for Figure 14 A magnified schematic diagram of a local area G; Figure 16 for Figure 10 A schematic diagram of the pressure plate structure.

[0020] The attached figures are labeled as follows: Box 1, lower shell 11, bottom plate 111, side plate 112, top cover 12, pressure plate component 2, sampling assembly 21, voltage sampling component 211, main body 2111, connecting part 2112, voltage sampling terminal 2113, temperature sampling component 212, wire harness 2121, temperature sampling terminal 2122, pressure plate 22, first opening 221, second opening 222, third opening 223, vent 224, raised part 225, cell stack 3, soft-pack cell 31, adhesive block 4, adhesive component 5, vent channel 6. Detailed Implementation

[0021] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0022] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0023] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the present invention. However, it will be apparent to those skilled in the art that embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the present invention.

[0024] Please see Figures 1 to 3 , Figure 5 and Figure 6 In some optional embodiments, the present invention provides a battery pack, which includes a housing 1, a cell stack 3, and a pressure plate component 2; in addition to the above-mentioned components, the battery pack may also include an adhesive component 5. The housing 1 includes a lower shell 11 and an upper cover 12. The cell stack 3 has a plurality of soft-pack cells 31. The cell stack 3 is installed inside the lower shell 11, and the bottom side of the cell stack 3 is connected and fixed to the bottom plate 111 of the lower shell 11. The upper cover 12 is located on the top side of the cell stack 3 and is connected to the lower shell 11 to cover the cell stack 3 inside the lower shell 11. The pressure plate component 2 includes a sampling component 21 and a pressure plate 22. The pressure plate 22 is located between the top side of the cell stack 3 and the upper cover 12. The pressure plate 22 is connected to the lower shell 11 and presses against the top side of the cell stack 3. The sampling component 21 is installed on the pressure plate 22 and is connected to the cell stack 3 for sampling.

[0025] Optionally, expanding foam is used to fill the space between the tab side of the cell stack 3 and the side plate 112 of the lower housing 11. This means the tab side of the cell stack 3 and the side plate 112 of the lower housing 11 can be connected by expanding foam, allowing insulation and sealing between the tabs of adjacent pouch cells 31 and between the pouch cells 31 and the lower housing 11. This improves the structural stability and impact resistance at the tabs of the pouch cells 31, enhances the overall structural stability, and prevents high-temperature flue gas from escaping through the tab side of the cell stack 3, reducing the risk of short circuits and heat spread at the tab side of the cell stack 3. Furthermore, some side plates 112 of the lower housing 11 are formed as side beams, and some side plates 112 are formed as central beams. Expanding foam can be placed between the tab-bearing side of the cell stack 3 and the side beam of the lower housing 11, and between the tab-bearing side of the cell stack 3 and the central beam of the lower housing 11.

[0026] Optionally, the bottom side of the cell stack 3 is directly bonded and fixed to the bottom plate 111 of the lower housing 11 using thermally conductive structural adhesive. The connection is stable and reliable, and easy to operate. In particular, the bottom side and the tab side of the cell stack 3 are simultaneously connected and fixed to the lower housing 11, making the connection more secure and stable. The cell stack 3 is less prone to shaking, the overall structure is more stable, and the impact resistance is stronger.

[0027] In the battery pack of the above embodiment, the pressure plate 22 presses against the top side of the cell stack 3, and the pressure plate 22 is connected to the lower housing 11, so that the pressure plate 22 can stably press against the cell stack 3, which is beneficial to improving the overall structural stability of the cell stack 3, thereby improving the overall structural stability of the battery pack. In addition, the sampling component 21 is integrated on the pressure plate 22, so that the pressure plate 22 and the sampling component 21 can be positioned and assembled synchronously, which is beneficial to reducing the number of parts and tooling, thereby improving assembly efficiency, increasing the energy density of the battery pack and reducing costs.

[0028] See Figures 1 to 8 In some alternative embodiments, the pressure plate 22 is connected and fixed to the side plate 112 of the lower housing 11, and the pressure plate 22 is adapted to press against the top side of the cell stack 3 when connected to the side plate 112 of the lower housing 11.

[0029] Optionally, the two ends of the pressure plate 22 are connected and fixed to the side plates 112, which are formed as edge beams and middle beams, respectively.

[0030] Optionally, the pressure plate 22 is connected and fixed to the side plate 112 of the lower housing 11 by a locking device. Furthermore, the locking device includes screws, making the connection simple and reliable.

[0031] In the battery pack of the above embodiment, the pressure plate 22 and the side plate 112 of the lower housing 11 can be connected in place and simultaneously pressed against the top side of the cell stack 3, which is simple and convenient to assemble and helps to improve assembly efficiency.

[0032] See Figure 1 , Figure 6 and Figure 8 In some alternative embodiments, the pressure plate 22 is bonded and fixed to the top side of the cell stack 3.

[0033] Optionally, the pressure plate 22 is bonded and fixed to the top side of the cell stack 3 by adhesive block 4. The adhesive block 4 extends along the stacking direction of the multiple soft-pack cells 31, so that the pressure plate 22 can be connected to the multiple soft-pack cells 31, so as to connect the multiple soft-pack cells 31 together, which is beneficial to improving the overall structural stability of the cell stack 3.

[0034] Optionally, there can be multiple adhesive blocks 4, which are distributed at intervals along the length of the soft-pack battery cell 31, ensuring a firm and reliable connection and improving the overall structural stability.

[0035] In the battery pack of the above embodiment, the pressure plate 22 is bonded and fixed to the top side of the cell stack 3, so that the pressure plate 22 is not easy to detach from the cell stack 3, the connection is stable and reliable, and it is beneficial to improve the stability of the overall structure.

[0036] See Figures 1 to 9In some alternative embodiments, the pressure plate 22 has a first opening 221, and the sampling component 21 includes a voltage sampling element 211. The voltage sampling element 211 is electrically connected to the cell stack 3 and is installed on the pressure plate 22 through the first opening 221.

[0037] Optionally, in some specific embodiments, the voltage sampling component 211 includes a flexible circuit board having a main board body 2111 and a voltage sampling terminal 2113. A portion of the main board body 2111 is located on the tab side of the cell stack 3 and is electrically connected to the tabs on the tab side of the cell stack 3 through the voltage sampling terminal 2113. A partial bend of the main board body 2111 forms a connecting portion 2112, which passes through the first opening 221 and is fixedly mounted on the top side of the pressure plate 22. Further, the voltage sampling terminal 2113 includes a nickel strip, which is electrically connected to the tabs of the pouch cell 31.

[0038] Optionally, in other specific embodiments, the voltage sampling component 211 includes a flexible circuit board and an insulating connecting piece. The flexible circuit board is located on the tab side of the cell stack 3 and is electrically connected to the cell stack 3 for sampling. One end of the insulating connecting piece is connected to the flexible circuit board, and the other end of the insulating connecting piece passes through the first opening 221 and is fixedly mounted on the top side of the pressure plate 22. Further, the flexible circuit board includes a main board body 2111 and a voltage sampling terminal 2113. The main board body 2111 is located on the tab side of the cell stack 3 and is electrically connected to the tabs on the tab side of the cell stack 3 through the voltage sampling terminal 2113. The insulating connecting piece is connected to the main board body 2111 to mount the flexible circuit board on the pressure plate 22. The voltage sampling terminal 2113 includes a nickel strip, which is electrically connected to the tabs of the pouch cell 31.

[0039] In the battery pack of the above embodiment, the voltage sampling component 211 is integrated on the pressure plate 22, which simplifies assembly and helps to improve assembly efficiency and reduce costs.

[0040] See Figures 1 to 9 In some optional embodiments, the pressure plate 22 has a second opening 222, and the sampling component 21 includes a temperature sampling element 212. The temperature sampling element 212 has a connected wire harness 2121 and a temperature sampling terminal 2122. The temperature sampling terminal 2122 is installed in the second opening 222 and is bonded and fixed to the top side of the cell stack 3 for sampling. The wire harness 2121 is arranged in a limited manner in the second opening 222. The adhesive 5 is connected to the pressure plate 22 and the wire harness 2121 respectively and presses against the limited wire harness 2121.

[0041] Optionally, the temperature sampling terminal 2122 may include a thermistor, such as a negative temperature coefficient thermistor.

[0042] Optionally, adhesive component 5 may include insulating tape.

[0043] In the battery pack of the above embodiment, the temperature sampling element 212 is integrated on the pressure plate 22, which simplifies assembly and helps to improve assembly efficiency and reduce costs.

[0044] See Figures 10 to 16 In some optional embodiments, the pressure plate 22 has a third opening 223. The sampling assembly 21 includes a temperature sampling element 212, which has a wire harness 2121 and a temperature sampling terminal 2122. The wire harness 2121 is placed on the top side of the pressure plate 22. The temperature sampling terminal 2122, which is connected to the wire harness 2121, passes through the third opening 223 and is sandwiched between the bottom side of the pressure plate 22 and the top side of the cell stack 3. The temperature sampling terminal 2122 contacts the cell stack 3 for sampling. The temperature sampling element 212 is integrated on the pressure plate 22, which simplifies assembly, improves assembly efficiency, and reduces costs. Moreover, the wire harness 2121 is placed on the top side of the pressure plate 22, and the temperature sampling terminal 2122, after passing through the third opening 223, is located between the cell stack 3 and the pressure plate 22 and is pressed and fixed by the pressure plate 22. No additional glue is required for fixation, which simplifies the assembly process and reduces costs.

[0045] See Figure 10 , Figure 11 , Figure 15 and Figure 16 In some alternative embodiments, the pressure plate 22 is provided with an exhaust hole 224 facing the upper cover 12. The exhaust hole 224 is used to discharge the high-temperature flue gas generated when the battery cell stack 3 experiences thermal runaway.

[0046] Optionally, the adhesive block 4 is staggered from the vent hole 224 to avoid interfering with the vent hole 224's exhaust.

[0047] Optionally, a portion of the pressure plate 22 is raised in a direction away from the top side of the cell stack 3 to form a raised portion 225. The raised portion 225 cooperates with the top side of the cell stack 3 to define an exhaust channel 6. An exhaust hole 224 is provided on the raised portion 225 and communicates with the exhaust channel 6.

[0048] Optionally, there are multiple raised portions 225. These raised portions 225 cooperate with the top side of the cell stack 3 to define multiple exhaust channels 6. The multiple exhaust channels 6 are spaced apart along the length of the soft-pack cell 31, which facilitates the discharge of high-temperature flue gas from multiple locations and achieves high exhaust efficiency. Furthermore, the adhesive block 4 is located between two adjacent exhaust channels 6. When connecting the pressure plate 2 and the cell stack 3, the adhesive block 4 can also separate two adjacent exhaust channels 6, which helps to reduce the risk of heat spread.

[0049] Optionally, the exhaust channel 6 extends along the stacking direction of the multiple pouch cells 31, and the raised portion 225 is provided with multiple exhaust holes 224. The multiple exhaust holes 224 are distributed at intervals along the extension direction of the exhaust channel 6. The same exhaust channel 6 can act on multiple pouch cells 31. The structure is simple, the layout is compact, the space utilization is high, and it is beneficial to improve the energy density of the battery pack.

[0050] In the battery pack of the above embodiment, the high-temperature flue gas generated when thermal runaway occurs in the cell stack 3 can be discharged in time through the exhaust port 224, which helps to reduce the risk of thermal spread and improve the safety of the battery pack.

[0051] The battery pack of this utility model increases the structural stability of the cell stack 3 by setting a pressure plate 22 on the top side of the cell stack 3, thereby improving the overall structural stability of the battery pack. In addition, the pressure plate 22 can provide installation support for the sampling component 21, realize the positioning and fixation of the sampling component 21. The integration of the sampling component 21 on the pressure plate 22 is also conducive to simplifying the structure, improving assembly efficiency and space utilization, thereby improving the energy density of the battery pack and reducing costs.

[0052] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A battery pack, characterized in that, include: The housing includes a lower shell; A battery cell stack having multiple pouch cells, the battery cell stack being installed inside the lower housing, and the bottom side of the battery cell stack being connected and fixed to the bottom plate of the lower housing; The pressure plate component includes a sampling assembly and a pressure plate. The pressure plate is connected to the lower housing and presses against the top side of the cell stack. The sampling assembly is mounted on the pressure plate and connected to the cell stack for sampling.

2. The battery pack according to claim 1, characterized in that, The pressure plate is connected and fixed to the side plate of the lower housing, and is adapted to press against the top side of the cell stack when connected to the side plate of the lower housing.

3. The battery pack according to claim 1, characterized in that, The pressure plate is bonded and fixed to the top side of the cell stack by an adhesive block, which extends along the stacking direction of the multiple soft-pack cells.

4. The battery pack according to claim 1, characterized in that, The pressure plate has a first opening, and the sampling component includes a voltage sampling element, which is electrically connected to the battery cell stack and is mounted on the pressure plate through the first opening.

5. The battery pack according to claim 4, characterized in that, The voltage sampling device includes a flexible circuit board with a main board body and voltage sampling terminals. A portion of the main board body is located on the tab side of the cell stack and is electrically connected to the cell stack through the voltage sampling terminals. A partial bend of the main board body forms a connecting portion, which passes through the first opening and is fixedly installed on the top side of the pressure plate.

6. The battery pack according to claim 4, characterized in that, The voltage sampling device includes a flexible circuit board and an insulating connecting piece. The flexible circuit board is located on the tab side of the cell stack and is electrically connected to the cell stack for sampling. One end of the insulating connecting piece is connected to the flexible circuit board, and the other end of the insulating connecting piece passes through the first opening and is fixedly installed on the top side of the pressure plate.

7. The battery pack according to claim 1, characterized in that, The battery pack also includes an adhesive component. The pressure plate has a second opening. The sampling component includes a temperature sampling component with a connected wire harness and a temperature sampling terminal. The temperature sampling terminal is installed in the second opening and is bonded and fixed to the top side of the cell stack for sampling. The wire harness is arranged in a limiting manner in the second opening. The adhesive component is connected to the pressure plate and the wire harness respectively and presses against and limits the wire harness.

8. The battery pack according to claim 1, characterized in that, The pressure plate has a third opening. The sampling component includes a temperature sampling element. The temperature sampling element has a wire harness and a temperature sampling terminal. The wire harness is placed on the top side of the pressure plate. The temperature sampling terminal connected to the wire harness passes through the third opening and is sandwiched between the pressure plate and the top side of the cell stack, and contacts the cell stack for sampling.

9. The battery pack according to claim 1, characterized in that, The housing also includes an upper cover, which is connected to the lower housing to enclose the battery cell stack inside the lower housing. The pressure plate has an exhaust hole facing the upper cover.

10. The battery pack according to claim 9, characterized in that, A portion of the pressure plate protrudes in a direction away from the top side of the cell stack to form a raised portion. The raised portion cooperates with the top side of the cell stack to define an exhaust channel. The exhaust hole is provided on the raised portion and communicates with the exhaust channel.

11. The battery pack according to claim 10, characterized in that, The number of raised portions is multiple, and the multiple raised portions cooperate with the top side of the cell stack to define multiple exhaust channels, and the multiple exhaust channels are distributed at intervals along the length direction of the pouch cell.

12. The battery pack according to claim 10, characterized in that, The exhaust channel extends along the stacking direction of the plurality of pouch cells, and the raised portion is provided with a plurality of exhaust holes, which are spaced apart along the extension direction of the exhaust channel.

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