Cells contact piece, cells contact system and battery pack

Abstract

Disclosed in the present application are a cells contact piece, a cells contact system and a battery pack. The cells contact piece comprises cells contact sub-pieces and flexible conductive connecting pieces, wherein a plurality of cells contact sub-pieces are provided, and the plurality of cells contact sub-pieces are respectively used for collecting working signals of a plurality of battery cell groups; and a connecting piece is provided between every two adjacent cells contact sub-pieces, two ends of each connecting piece are respectively connected to two cells contact sub-pieces adjacent thereto, and each connecting piece has a first bending structure, the first bending structure being configured to deform when two battery cell groups move away from or close to each other.

Description

Acquisition chips, acquisition components and battery packs

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 31, 2023, with application number 202323671458.3, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a collection sheet, a collection component and a battery pack. Background Art

[0003] In related technologies, a battery pack includes a housing, battery modules housed within the housing, a battery management system (BMS) board, and a data acquisition component that electrically connects the battery modules to the BMS board. The data acquisition component (CCS) includes a busbar electrically connected to the battery cells in the battery module and a data acquisition chip electrically connected to the busbar and cells. The data acquisition chip is typically a flexible printed circuit (FPC). This chip transmits the temperature and voltage signals of the battery cells to the BMS board via a wiring harness and connector.

[0004] When a battery module includes multiple cell groups, a single acquisition chip is typically used to collect temperature and voltage signals from multiple cell groups to reduce the number of electrical components and ease wiring. During use, the cells expand due to rising temperatures, which exerts tension on the acquisition chip soldered to the cells. This can cause the solder joints between the acquisition chip and the cells to break, or even tear the chip, reducing the reliability of the acquired results. SUMMARY OF THE INVENTION

[0005] The present application provides a collection piece, a collection component and a battery pack to solve the above technical problems.

[0006] In the first aspect, an embodiment of the present application provides a collection sheet, which is applied to a battery module, the battery module includes multiple battery cell groups, and the collection sheet includes a collection sub-sheet and a flexible conductive connecting sheet; there are multiple collection sub-sheets, and the multiple collection sub-sheets are arranged in sequence and in parallel, and the multiple collection sub-sheets are respectively configured to collect working signals of multiple battery cell groups; a connecting sheet is provided between two adjacent collection sub-sheets, and the two ends of the connecting sheet are respectively connected to the two adjacent collection sub-sheets, and the connecting sheet is provided with a first bending structure, and the first bending structure is configured to deform when the two battery cell groups move away from or approach each other.

[0007] In a second aspect, an embodiment of the present application provides a collection component, which includes a collection bracket, a bus group and the aforementioned collection piece; there are multiple bus groups, and the multiple bus groups are arranged in parallel on the collection bracket, and the multiple bus groups are respectively arranged to be connected to multiple battery cell groups; multiple collection sub-pieces are respectively connected to the multiple bus groups, and the connecting piece is located between two adjacent bus groups.

[0008] In a third aspect, an embodiment of the present application provides a battery pack, comprising a battery box, a battery module, a BMS board and the aforementioned acquisition component; the battery box has a first accommodating cavity and a second accommodating cavity distributed along the longitudinal direction; the battery module is arranged in the first accommodating cavity, and the battery module includes a plurality of battery cell groups distributed along the longitudinal direction; the BMS board is arranged in the second accommodating cavity; the acquisition component is arranged in the first accommodating cavity; wherein, the plurality of busbar groups are respectively connected to the plurality of battery cell groups, and the output of the plurality of acquisition sub-chips, and the first signal output end of the acquisition sub-chip is connected to the BMS board. Beneficial effects

[0009] The beneficial effects of this application are:

[0010] The collection sheet provided in the present application has a buffer portion formed based on the first bending structure by providing a first bending structure at a portion of the collection sheet between two battery cell groups. As a result, when the battery cell groups generate heat and expand, the buffer portion can deform to buffer the pulling of the collection sheet caused by the expansion between the battery cell groups, thereby improving the stability of the welding portion between the collection sheet and the battery cell, and preventing the collection sheet from being torn, thereby ultimately improving the reliability of the collection sheet.

[0011] The collection component provided in the present application adopts the above-mentioned collection sheet. When the battery cell group generates heat and expands, the first bending structure can be used to generate deformation to buffer the pulling of the collection sheet by the expansion between the battery cell groups, thereby improving the stability of the welding part between the collection sheet and the battery cell, and preventing the collection sheet from being torn, thereby ultimately improving the reliability of the collection component.

[0012] The battery pack provided in the present application adopts the above-mentioned collection component. When the battery cell group generates heat and expands, the first bending structure can be used to generate deformation to buffer the pulling of the collection sheet caused by the expansion between the battery cell groups, thereby improving the stability of the welding part between the collection sheet and the battery cell, and preventing the collection sheet from being torn, thereby ultimately improving the reliability of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG1 is a schematic structural diagram of a collection sheet provided in an embodiment of the present application;

[0014] FIG2 is a side view of a collection sheet provided in an embodiment of the present application;

[0015] FIG3 is an enlarged view of point A in FIG1 ;

[0016] FIG4 is a schematic diagram of the structure of the acquisition component provided in an embodiment of the present application;

[0017] FIG5 is an enlarged view of point B in FIG4 ;

[0018] FIG6 is an enlarged view of point C in FIG4 ;

[0019] FIG7 is an enlarged view of point D in FIG4 ;

[0020] FIG8 is a schematic structural diagram of a battery pack provided in an embodiment of the present application;

[0021] FIG9 is a schematic diagram of the connection between the battery charging and discharging interface of the battery pack and the BDU provided in an embodiment of the present application;

[0022] FIG10 is a wiring diagram of a collection harness of a battery pack provided in an embodiment of the present application.

[0023] Description of reference numerals:

[0024] 001, acquisition component; 011, acquisition piece; 111, acquisition sub-piece; 1111, first signal output terminal; 1112, second bending structure; 1113, voltage acquisition area; 1114, acquisition notch; 1115, acquisition end piece; 11151, buffer notch; 1116, gap; 1117, connecting strip; 11171, cutting notch; 112, connecting piece; 1121, first bending structure; 11211, first surface; 113, bent end piece; 012, acquisition bracket; 121, groove; 013, bus bar group; 131, bus bar ;132. Conductive sheet;002. Battery box;021. First accommodating cavity;022. Second accommodating cavity;023. Crossbeam;024. Longitudinal beam;025. End partition;031. Positive electrode of BDU;032. Negative electrode of BDU;041. Charging positive electrode row;042. Discharging positive electrode row;043. Charging and discharging negative electrode row;051. Charging interface;052. Discharging interface;061. BMS main board;062. BMS slave board;063. Connector;071. Fast charging interface;072. Communication interface;008. Battery module;081. Battery cell group. Modes for Carrying Out the Invention

[0025] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0026] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0027] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meanings.

[0028] To address the problem of battery cells heating up and expanding, which pulls on the collection sheet, causing the welds between the collection sheet and the battery cells to fall off, or even tearing the collection sheet, reducing collection reliability, the present application provides a collection sheet, collection assembly, and battery pack. The following examples are specifically described using a battery module comprising two battery cell groups.

[0029] Please refer to Figure 1, which is a structural schematic diagram of the collection piece 011 provided in an embodiment of the present application. An embodiment of the present application provides a collection piece 011, which is applied to a battery module. The battery module includes two battery cell groups. The collection piece 011 includes a collection sub-piece 111 and a flexible conductive connecting piece 112. There are two collection sub-pieces 111. The two collection sub-pieces 111 are arranged in parallel in sequence. The two collection sub-pieces 111 are respectively configured to collect working signals of the two battery cell groups. The connecting piece 112 is arranged between the two collection sub-pieces 111. The two ends of the connecting piece 112 are respectively connected to the two collection sub-pieces 111, and the connecting piece 112 is provided with a first bending structure 1121, and the first bending structure 1121 is configured to deform when the two battery cell groups move away from or approach each other.

[0030] It is understood that when two battery cell groups move away from or toward each other, the first bent structure 1121 undergoes flexible deformation due to the flexibility of the connecting piece 112. When the connecting piece 112 is a resilient metal sheet, the first bent structure 1121 also undergoes elastic deformation. The operating signals are primarily the voltage signals of the battery cells and the temperature signals of the battery cell groups.

[0031] In addition, the acquisition sub-chip 111 has a voltage acquisition area 1113, which is connected to the bus 131, and the bus 131 is connected to the battery cell, so that the acquisition sub-chip 111 can collect the voltage signal of the battery cell. The battery cell group includes multiple battery cells connected in series or in parallel through the bus 131.

[0032] Exemplarily, the collection sub-sheet 111 and the connection sheet 112 are both flexible circuit boards, and the collection sheet 011 is an integrally formed part. The flexible circuit board is a structure formed by integrally etching aluminum foil or copper foil to have a plurality of circuits for transmitting electrical signals.

[0033] In this embodiment, a first bending structure 1121 is provided at a portion of the collection sheet 011 between two battery cell groups, so that the collection sheet 011 has a buffer portion formed based on the first bending structure 1121. When the battery cell groups generate heat and expand, the buffer portion can be deformed to buffer the pulling of the collection sheet 011 caused by the expansion between the battery cell groups, thereby improving the stability of the welding portion between the collection sheet 011 and the battery cell, and preventing the collection sheet 011 from being torn, thereby improving the reliability of the collection sheet 011.

[0034] In addition, due to the assembly tolerance between the cell group and the battery box 002, when the cell group is assembled into the battery box 002, the first bent structure 1121 can be squeezed or stretched to make the two collection sub-sheets 111 adapt to the assembly position of the cell group, thereby improving the pulling or squeezing of the connection between the collection sheet 011 and the cell group caused by assembly error, thereby improving the reliability of the connection between the collection sheet 011 and the cell group.

[0035] Please refer to Figure 2, which is a side view of the collection sheet 011 provided in an embodiment of the present application. In one embodiment, the connecting sheet 112 includes a connecting sheet body and a first bending structure 1121. The first bending structure 1121 is protruded from the location of the connecting sheet 112 toward the battery cell group.

[0036] As can be understood, a busbar 131 is provided between the acquisition sub-sheet 111 and the battery cells. The voltage acquisition area 1113 of the acquisition sheet 011 is welded to the busbar 131 to collect the voltage information of the battery cells. The first bent structure 1121 is not used for collecting voltage signals, so its side facing the battery cell group serves as the acquisition bracket 012.

[0037] Based on this, in this embodiment, by protruding the first bending structure 1121 from the position of the connecting piece 112 toward the battery cell group, the collection piece 011 can have a structure for buffering the collection piece 011 from being pulled or squeezed, and the first bending structure 1121 overlaps with the bus 131 in the axial direction of the battery cell, thereby avoiding the setting of the first bending structure 1121 to increase the height of the collection assembly 001, which is beneficial to the arrangement of electrical components inside the battery pack.

[0038] 2 , in one embodiment, the first bending structure 1121 has a first surface 11211 , which is located in the middle of the first bending structure 1121 and faces the battery cell group. The first surface 11211 is parallel to the collection sub-sheet 111 .

[0039] It can be understood that the first bending structure 1121 is a U-shaped structure protruding toward the battery cell group, and the side of the middle portion facing the battery cell group is the first surface 11211. Specifically, the connecting piece 112 includes two extension sections and a first bending structure 1121 located between the two extension sections. The two extension sections are respectively connected to the two collection sub-sheets 111. The first bending structure 1121 includes a first bending section, a second bending section, and a third bending section connected in sequence. The first bending section and the third bending section are arranged opposite to each other. The ends of the first bending section and the third bending section facing away from the second bending section are respectively connected to the two extension sections. The side of the second bending section facing the battery cell group is the first surface 11211.

[0040] In this embodiment, through the above arrangement, the first bending structure 1121 has a longer length in a certain space, so that the first bending structure 1121 has a larger buffer size, and further the first bending structure 1121 can play a better buffering effect in a limited space.

[0041] Please refer to FIG. 2 . In one embodiment, the corners of the first bending structure 1121 are all rounded.

[0042] It is understood that the connection between an extension segment and the first bend segment, the connection between the first bend segment and the second bend segment, the connection between the second bend segment and the third bend segment, and the connection between the third bend segment and another extension segment are all corners. Rounded corners are provided at these connections. These rounded corners are formed by bending the connecting piece 112.

[0043] In this embodiment, by providing rounded corners at the corners of the first bending structure 1121 , stress at the corners can be reduced, thereby improving the impact resistance of the collection piece 011 and further improving the reliability of the collection piece 011 .

[0044] Referring to Figure 2 , in one embodiment, one of the two acquisition sub-chips 111 is an output acquisition sub-chip 111. The output acquisition sub-chip 111 has a first signal output terminal 1111. The output acquisition sub-chip 111 is provided with a second bending structure 1112, which is disposed adjacent to the first signal output terminal 1111. The second bending structure 1112 is configured to deform when the first signal output terminal 1111 and the battery cell group move away from or approach each other.

[0045] It can be understood that the first signal output terminal 1111 is connected to the BMS board. Typically, the first signal output terminal 1111 is connected to the BMS board via connector 063 to transmit the collected working signal to the BMS board. In addition, of the two acquisition sub-chips 111, the acquisition sub-chip 111 closer to the BMS board is the output acquisition sub-chip 111, and the end of the output acquisition sub-chip 111 closer to the BMS board is the first signal output terminal 1111.

[0046] Since the first signal output terminal 1111 is connected to the BMS board, the first signal output terminal 1111 is fixed. When the battery cell generates heat and expands, it will pull on the connection between the first signal terminal and the BMS board. Based on this, in this embodiment, by providing a second bending structure 1112 at one end of the output acquisition sub-piece 111 close to the first signal output terminal 1111, the end of the output acquisition sub-piece 111 close to the first signal output terminal 1111 has a structure for buffering the pulling of the first signal terminal when the battery cell group expands, thereby improving the reliability of the connection between the acquisition piece 011 and the BMS board and preventing the acquisition piece 011 from being torn.

[0047] Please refer to FIG. 2 . In one embodiment, the second bending structure 1112 is an arc-shaped structure, and its inner concave surface faces away from the first signal output end 1111 .

[0048] Illustratively, a side of the second bending structure 1112 facing away from the first signal output end 1111 is tangent to a side of the acquisition sub-chip 111 located on the second bending structure 1112 facing away from the first signal output end 1111 .

[0049] In this embodiment, by setting the second bending structure 1112 as an arc-shaped structure, the stress of the second bending structure 1112 can be reduced, thereby improving the impact resistance of the collection piece 011 and further improving the reliability of the collection piece 011.

[0050] Please refer to Figure 3, which is an enlarged view of point A in Figure 1. In one embodiment, the collection sub-sheet 111 has a voltage collection area 1113. The voltage collection area 1113 is provided with a collection notch 1114. A collection terminal 1115 configured to collect the voltage of the battery cell group is disposed in the collection notch 1114. The collection terminal 1115 has opposing first and second ends. The first end is connected to one side of the collection notch 1114. The second end is connected to the other side of the collection notch 114. A gap 1116 is defined between the collection terminal 1115 and the collection notch 1114, extending from the first end toward the second end.

[0051] It can be understood that the voltage collection area 1113 is the area on the collection sub-chip 111 that is connected to the busbar 131. Specifically, the collection terminal 1115 is welded to the busbar 131 to collect voltage information of the battery cell.

[0052] In this embodiment, through the above-mentioned arrangement, on the one hand, the collection sub-piece 111 can collect the voltage information of the battery cell; on the other hand, the pulling force on the collection terminal piece 1115 when the battery cell expands mainly acts on the first end and the second end of the collection terminal piece 1115, thereby reducing the pulling force on the collection terminal piece 1115, thereby preventing the solder joint between the collection terminal piece 1115 and the bus 131 from falling off, thereby improving the stability of the connection between the collection terminal piece 1115 and the bus 131.

[0053] 3 , in one embodiment, the second end of the collecting end piece 1115 is connected to the other side surface of the collecting notch 1114 via a connecting structure. The connecting structure is configured to be disconnected when the collecting sub-piece 111 is pulled.

[0054] It is understood that the pulling force required to disconnect the connection structure is less than the pulling force required to disconnect the collection end piece 1115 from the busbar 131. Furthermore, the connection structure secures the collection end piece 1115 within the collection notch 1114, preventing the second end of the collection end piece 1115 from falling due to gravity and folding, thereby ensuring convenient assembly of the collection piece.

[0055] In this embodiment, by connecting the second end of the collecting end piece 1115 to the surface of the collecting notch 1114 through a connecting structure, when the collecting end piece 1115 is subjected to a large pulling force, the connecting structure at one end of the collecting end piece 1115 can be disconnected by the pulling force to reduce the pulling force borne by the collecting end piece 1115, thereby preventing the weld between the collecting end piece 1115 and the bus 131 from falling off, and further improving the stability of the connection between the collecting end piece 1115 and the bus 131.

[0056] The connecting structure can be made of a thinner material than the collection end piece 1115, or a material with lower strength than the connection between the first end of the collection end piece 1115 and the collection notch 1114. Specifically, the connecting structure includes a connecting strip 1117. The ends of the connecting strip 1117 are connected to the second end of the collection end piece 1115 and the surface of the collection notch 1114, respectively. A cutting notch 11171 is provided in the middle of the connecting strip 1117. Cutting notch 11171 is configured to break when the collection sub-piece 111 is pulled.

[0057] 3 , in one embodiment, a buffer notch 11151 is provided on the collection end piece 1115 . The buffer notch 11151 is located between the first end and the second end of the collection end piece 1115 .

[0058] In this embodiment, by providing the buffer notch 11151 , the stress of the collection end piece 1115 when it expands due to heat can be relieved, thereby improving the stability of the connection between the collection end piece 1115 and the bus bar 131 .

[0059] Please refer to FIG. 1 . In one embodiment, a bent end piece 113 configured to collect the temperature of the battery cell group is connected to the edge of the collection sub-piece 111 .

[0060] It can be understood that the bent end piece 113 is located at the outer edge of the collecting sub-piece 111 and is integrally formed with the collecting sub-piece 111 .

[0061] In this embodiment, the temperature information of the battery cell group is collected by using the bent end piece 113. The deformation ability of the bent end piece 113 can be used to buffer the pulling of the collection piece 011 caused by the thermal expansion of the battery cell, thereby improving the load-bearing capacity of the collection piece 011, and further preventing the collection piece 011 from being torn or the disconnection between the bent end piece 113 and the collection sub-piece 111, thereby improving the reliability of the collection piece 011.

[0062] Please refer to Figure 4, which is a schematic diagram of the structure of a collection assembly 001 provided in an embodiment of the present application. Accordingly, an embodiment of the present application provides a collection assembly 001. Collection assembly 001 includes a collection bracket 012, a busbar group 013, and the aforementioned collection sheet 011. There are two busbar groups 013. These two busbar groups 013 are arranged side by side on collection bracket 012. The two busbar groups 013 are respectively configured to connect to two battery cell groups. Two collection sub-sheets 111 are respectively connected to the two busbar groups 013. A connecting sheet 112 is located between two adjacent busbar groups 013.

[0063] Exemplarily, there are two first bending structures 1121, and they are spaced apart along the arrangement direction of the two collecting sub-sheets 111. The first bending structure 1121 protrudes from the position of the connecting sheet 112 toward the battery cell group. The collecting sub-sheet 111 is provided on the collecting bracket 012. A groove 121 is provided on the collecting bracket 012. There are two grooves 121. The two first bending structures 1121 are respectively located in the two grooves 121, as shown in FIG5 , which is an enlarged view of point B in FIG4 . The first bending structure 1121 cooperates with the gap 1116 in the groove 121. The gap 1116 between the first bending structure 1121 and the groove 121 is used to provide deformation space for the first bend, so that the deformation of the first bend is not hindered.

[0064] In addition, the inner concave surface of the second bending structure 1112 faces the end surface of the collection bracket 012, as shown in FIG6 , which is an enlarged view of point C in FIG4 .

[0065] The collection bracket 012 is a blister-shaped bracket. The busbar assembly 013 includes multiple busbars 131, which are used to connect two adjacent battery cells in parallel. Accordingly, the collection sub-piece 111 is provided with multiple voltage collection areas 1113, each of which is connected to a plurality of busbars 131. Busbars 131 are O-state aluminum bars. They are welded to the battery cell poles. The connection structure between busbars 131 and the collection sub-piece 111 is shown in Figure 7, which is an enlarged view of point D in Figure 4. The voltage collection areas 1113 of the collection sub-piece 111 are connected to the busbars 131 via conductive sheets 132. Specifically, one end of the conductive sheet 132 is welded to the portion of the collection terminal piece 1115 between the buffer notch 11151 and the second end of the collection terminal piece 1115, and the other end is welded to the end of the busbar 131 near the collection sub-piece 111.

[0066] In this embodiment, by adopting the aforementioned collection sheet 011, when the battery cell group generates heat and expands, the first bending structure 1121 can be used to generate deformation to buffer the pulling of the collection sheet 011 caused by the expansion between the battery cell groups, thereby improving the stability of the welding part between the collection sheet 011 and the battery cell, and preventing the collection sheet 011 from being torn, and ultimately improving the reliability of the collection component 001.

[0067] Please refer to Figure 8, which is a schematic diagram of the structure of a battery pack provided in an embodiment of the present application (to facilitate illustrating the internal structure of the battery pack, the cover of the battery box 002 is hidden in Figure 8). Accordingly, an embodiment of the present application also provides a battery pack comprising a battery box 002, a battery module 008, a battery management system (BMS) board, and the aforementioned data acquisition assembly 001. Battery box 002 has a first accommodating cavity 021 and a second accommodating cavity 022 arranged longitudinally. Battery module 008 is disposed in first accommodating cavity 021. Battery module 008 includes two cell groups 081 arranged longitudinally. The BMS board is disposed in second accommodating cavity 022. Data acquisition assembly 001 is disposed in first accommodating cavity 021. Two busbars 131 are connected to the two cell groups 081, respectively. One of the two data acquisition sub-chips 111 is an output data acquisition sub-chip 111. The first signal output terminal 1111 of the output data acquisition sub-chip 111 is connected to the BMS board. Specifically, the first signal output terminal 1111 is connected to the BMS board through the connector 063 .

[0068] Illustratively, the first accommodating cavity 021 and the second accommodating cavity 022 are separated by an end partition 025, forming the inner cavity of the battery pack. Furthermore, a crossbeam 023 is disposed within the first accommodating cavity 021. Crossbeam 023 is connected to the cavity wall of the first accommodating cavity 021. Crossbeam 023 is located between the two cell groups 081 of the battery module 008 to separate the two cell groups 081.

[0069] In this embodiment, by adopting the aforementioned collection component 001, when the battery cell group 081 generates heat and expands, the first bending structure can be used to generate deformation to buffer the pulling of the collection sheet 011 caused by the expansion between the battery cell group 081, thereby improving the stability of the welding part between the collection sheet 011 and the battery cell, and preventing the collection sheet 011 from being torn, thereby improving the reliability of the battery pack.

[0070] As shown in Figure 8, in one embodiment, there are four battery modules 008 and four collection assemblies 001. The four battery modules 008 are sequentially arranged in a transverse direction within the first accommodating cavity 021. The transverse direction is perpendicular to the longitudinal direction. The two battery modules 008 and the two collection assemblies 001 are arranged in a one-to-one correspondence. To enhance the installation stability of the battery modules 008, a longitudinal beam 024 is provided between adjacent battery modules 008. The longitudinal beam 024 is connected to the inner wall of the battery box 002.

[0071] It can be understood that the four battery modules 008 correspond to eight battery cell groups 081. The eight battery cell groups 081 are sequentially connected in series through O-state aluminum bars.

[0072] As shown in Figure 8, in one embodiment, the battery pack further includes a BDU (Battery Energy Distribution Unit), a battery charge and discharge interface, and a charge and discharge connection bar. The BDU is located in the second accommodating cavity 022, and the battery charge and discharge interface is located on the side of the battery box 002 facing away from the second accommodating cavity 022. The charge and discharge connection bar has two ends connected to the BDU and the battery charge and discharge interface, and the charge and discharge connection bar is located on the end of the longitudinal beam 024 facing away from the bottom wall of the battery box 002.

[0073] Exemplarily, the charge and discharge connection bar includes an intermediate bar and an end bar. There are two end bars, one end bar connects one end of the intermediate bar to the BDU, and the other end bar connects the other end of the intermediate bar to the battery charge and discharge interface, and the end bar is a soft metal bar. The intermediate bar is a 6 series aluminum bar, and the end bar is specifically a copper bar. The end bar and the intermediate bar are welded together by polymer diffusion welding. The soft copper bar can be deformed during installation, thereby effectively absorbing assembly tolerances, thereby improving the convenience of connecting the charge and discharge connection bar to the BDU and the battery charge and discharge interface. At the same time, during driving, the soft copper bar can absorb the pulling force caused by the vibration of the car very well, avoiding the high-voltage circuit disconnection or leakage caused by the pulling force of the charge and discharge connection bar.

[0074] In addition, the battery pack is also equipped with a fast charging interface 071. The fast charging interface 071 is located on the side of the battery pack close to the BDU.

[0075] In conventional installation methods, the charge and discharge connection bar is installed on the wall of the battery box 002. However, the charge and discharge connection bar needs to maintain a safe distance from the busbar 131 and the battery cells. Therefore, the first inner cavity needs to have sufficient space in the horizontal direction to accommodate the installation of related components while also ensuring a safe distance between the aforementioned components.

[0076] Based on this, in this embodiment, the charge-discharge connection bars are positioned on longitudinal beams 024. This, on the one hand, utilizes the space occupied by longitudinal beams 024, allowing the required installation space for the charge-discharge connection bars to overlap with the space occupied by longitudinal beams 024, thereby improving the internal space utilization of the battery pack. This allows the space originally reserved for the charge-discharge connection bars to be used to increase the lateral dimensions of the battery cells, thereby increasing the energy density of the battery pack. Furthermore, positioning the charge-discharge connection bars on longitudinal beams 024 prevents compression of the battery pack's outer walls, which could lead to cracking of the insulation layer of the charge-discharge connection bars, thereby improving the reliability of the battery pack.

[0077] Please refer to Figure 9, which is a schematic diagram of the connection between the battery charging and discharging interface of the battery pack and the BDU provided in an embodiment of the present application. In one embodiment, the battery charging and discharging interface includes a charging interface 051 and a discharging interface 052. The charging and discharging connection row includes a charging positive electrode row 041, a discharging positive electrode row 042, and a charging and discharging negative electrode row 043. The positive port of the charging interface 051 is connected to the positive electrode 031 port of the BDU through the charging positive electrode row 041. The positive port of the discharging interface 052 is connected to the positive electrode 031 port of the BDU through the discharging positive electrode row 042. One end of the charging and discharging negative electrode row 043 is connected to the negative electrode port of the charging interface 051 and the negative electrode port of the discharging interface 052, and the other end is connected to the negative electrode 032 port of the BDU.

[0078] In FIG9 , from left to right, the three long solid lines in the middle are the charging positive electrode row 041 , the charging and discharging negative electrode row 043 , and the discharging positive electrode row 042 .

[0079] In this embodiment, through the above arrangement, the negative electrode row for charging and the negative electrode row for discharging of the battery pack share a single metal row, thereby reducing the number of electrical components in the battery pack, thereby improving the assembly efficiency of the battery pack and reducing the manufacturing cost of the battery pack.

[0080] In addition, the wiring harness connection of part of the battery pack's signal collection is shown in Figure 10, which is a wiring diagram of the battery pack's signal collection harness provided by an embodiment of the present application. The BMS board includes a BMS main board 061 and three BMS slave boards 062.

[0081] It can be understood that the battery includes four battery modules 008. Each battery module 008 includes two battery cell groups 081. The two battery cell groups 081 include 25 battery cells and 26 battery cells respectively. Therefore, it has many signal sources, and only configuring one BMS main board 061 is not conducive to data processing. Based on this, the BMS board is set to one BMS main board 061 and three BMS slave boards 062, which can improve the data processing efficiency and thus improve the signal acquisition reliability of the battery pack. Specifically, the BMS slave board 062 converts the analog signal from the acquisition chip 011 into a digital signal, and then transmits the signal to the BMS main board 061 through a daisy chain. The BMS main board 061 is connected to the control system of the car through the communication interface 072.

Claims

1. A collecting sheet, which is applied to a battery module. The battery module includes a plurality of battery cell groups. The collecting sheet includes: A plurality of collecting sub-sheets, which are arranged in parallel in sequence. The plurality of collecting sub-sheets are respectively configured to collect the working signals of the plurality of battery cell groups; Flexible conductive connecting sheets. The connecting sheets are arranged between every two adjacent collecting sub-sheets. Two ends of each connecting sheet are respectively connected to two adjacent collecting sub-sheets. And the connecting sheet is provided with a first bending structure, which is configured to deform when the two battery cell groups move away from or close to each other.

2. The acquisition sheet according to claim 1, wherein, The connecting sheet includes a connecting sheet body and the first bending structure. The first bending structure protrudes from the position where the connecting sheet body is located towards the battery cell group.

3. The acquisition sheet according to claim 2, wherein, The first bending structure has a first surface, which is located in the middle of the first bending structure and faces the battery cell group. The first surface is parallel to the collecting sub-sheet.

4. The acquisition sheet according to claim 3, wherein, Round corners are provided at the corners of the first bending structure.

5. The collection sheet according to any one of claims 1-4, wherein, The plurality of collecting sub-sheets include an output collecting sub-sheet, which has a first signal output end. The output collecting sub-sheet is provided with a second bending structure, and the second bending structure is arranged close to the first signal output end. The second bending structure is configured to deform when the first signal output end and the battery cell group move away from or close to each other.

6. The acquisition sheet according to claim 5, wherein, The second bending structure is an arc structure, and its concave surface faces away from the first signal output end.

7. The acquisition sheet according to any one of claims 1-4, wherein, The collecting sub-sheet has a voltage collecting area, and a collecting notch is provided in the voltage collecting area. A collecting end sheet configured to collect the voltage of the battery cell group is arranged in the collecting notch. The collecting end sheet has opposite first end and second end. The first end is connected to one side surface of the collecting notch, and the second end is connected to the other side surface of the collecting notch; in the direction from the first end to the second end, there is a gap between the collecting end sheet and the collecting notch.

8. The acquisition sheet according to claim 7, wherein, The second end of the collecting end sheet is connected to the other side surface of the collecting notch through a connecting structure, and the connecting structure is configured to break when the collecting sub-sheet is pulled.

9. The acquisition sheet according to claim 8, wherein, The connecting structure includes a connecting strip. Two ends of the connecting strip are respectively connected to the second end of the collecting end sheet and the surface of the collecting notch. A cutting notch is provided in the middle of the connecting strip, and the cutting notch is configured to break when the collecting sub-sheet is pulled.

10. The acquisition sheet according to claim 7, wherein, A buffer notch is provided on the collecting end sheet, and the buffer notch is located between the first end and the second end of the collecting end sheet.

11. The acquisition sheet according to any one of claims 1-4, wherein, A bent end sheet configured to collect the temperature of the battery cell group is connected to the edge of the collecting sub-sheet.

12. A collecting assembly, including: A collecting bracket; A plurality of busbar groups, which are arranged in parallel on the collecting bracket. The plurality of busbar groups are respectively configured to be connected to the plurality of battery cell groups; The collecting sheet according to any one of claims 1-11, wherein the plurality of collecting sub-sheets are respectively connected to the plurality of busbar groups, and the connecting sheet is located between two adjacent busbar groups.

13. A battery pack, including: A battery box having a first accommodating cavity and a second accommodating cavity distributed in the longitudinal direction; A battery module is disposed in the first accommodating cavity, wherein the battery module comprises a plurality of battery cell groups distributed along the longitudinal direction; A BMS board is disposed in the second accommodation cavity; The collection assembly according to claim 12, wherein the collection assembly is disposed in the first accommodating chamber; The plurality of busbar groups are respectively connected to the plurality of cell groups, and the first signal output end of the output acquisition sub-chip of the plurality of acquisition sub-chips is connected to the BMS board.

14. The battery pack according to claim 13, wherein, There are multiple battery modules and multiple collection components, and the multiple battery modules are sequentially arranged in the first accommodating cavity along the transverse direction, the transverse direction is perpendicular to the longitudinal direction, and the multiple battery modules and the multiple collection components are arranged in a one-to-one correspondence.

15. The battery pack according to claim 14, wherein, A longitudinal beam is arranged between two adjacent battery modules, and the longitudinal beam is connected to the inner wall of the battery box.

16. The battery pack according to claim 15, further comprising a BDU, a battery charge and discharge interface and a charge and discharge connection bar, the BDU being arranged in the second accommodating cavity, the battery charge and discharge interface being arranged on a side of the battery box away from the second accommodating cavity, both ends of the charge and discharge connection bar being connected to the BDU and the battery charge and discharge interface, and the charge and discharge connection bar being arranged at an end of the longitudinal beam away from the bottom wall of the battery box.

17. The battery pack according to claim 16, wherein, The battery charge and discharge interface includes a charging interface and a discharging interface, the charge and discharge connection row includes a charging positive electrode row, a discharging positive electrode row and a charging and discharging negative electrode row, the positive electrode port of the charging interface is connected to the positive electrode port of the BDU through the charging positive electrode row, the positive electrode port of the discharging interface is connected to the positive electrode port of the BDU through the discharging positive electrode row, one end of the charge and discharge negative electrode row is connected to the negative electrode port of the charging interface and the negative electrode port of the discharging interface, and the other end is connected to the negative electrode port of the BDU.

18. The battery pack according to claim 16, wherein, The charge and discharge connection row includes a middle row and an end row. There are two end rows. One end row connects one end of the middle row to the BDU, and the other end row connects the other end of the middle row to the battery charge and discharge interface. The end rows are soft metal rows.

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