Battery pack

Abstract

To provide a battery pack that has a high spatial usage and high energy density, and that can be easily attached.SOLUTION: A battery pack includes a case including a lower part housing, a cell stack including a plurality of pouch type battery cells, two tab sides facing each other, and side surfaces adjacent to the tab sides, and installed inside the lower part housing, a thermal conductive adhesive that directly attaches and fixes between the cell stack and the bottom plate of the lower part housing, a foamed adhesive connected by filling a space between the tab side of the cell stack and the lower part housing, a battery management system, a flexible circuit board assembly including a flexible circuit board, side plates fixed at the side surfaces of the cell stack, and a connection component that connects the battery management system to the flexible circuit board by communication and includes a flexible flat cable and an adaptor sheet, in which the flexible flat cable is installed at the side surface of the cell stack and connected and fixed to the side plate through the adaptor sheet.SELECTED DRAWING: Figure 18

Description

[Technical Field]

[0001] The present invention relates to the technical field of power batteries, and in particular to battery packs. [Background technology]

[0002] The operating voltage of a single secondary battery is approximately 2.5V to 4.5V. In electric vehicles and energy storage systems that require large-capacity and high-voltage output, a plurality of cells are typically connected in series and / or parallel to form a battery module, and the battery modules are then connected in series and / or parallel to form a battery pack, which is then used as an energy source system for supplying energy to an electric vehicle or as an energy storage system. The number and shape of the battery modules used to construct the battery pack, and the number and shape of the cells used to configure the battery module, can be flexibly changed according to actual needs.

[0003] In the field of power batteries used in electric vehicles, the energy density and cooling performance of battery packs need to be further improved to improve the driving range and charging speed of electric vehicles.One method of improving energy density is the cell-to-pack (CTP) type battery pack, which omits the step of forming a battery module from cells and directly integrates the cells into the battery pack, thereby eliminating the structural components and electrical connection components required to form the battery module and increasing the space available for the cells themselves.

[0004] Currently, common cells are classified into cylindrical cells, prismatic cells, pouch-type cells, etc. based on their structure. CTP battery packs using prismatic cells have already been widely adopted, but pouch-type battery cells have the disadvantages of being vulnerable to external impact and difficult to assemble, so there are still a series of problems to be faced when integrating them into CTP battery packs. With current technology, it is difficult to directly install a stack of pouch-type battery cells into a battery pack, which results in low space utilization and a decrease in the energy density of the battery pack. Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above-mentioned drawbacks of the existing technology, the present invention aims to provide a battery pack with high space utilization, high energy density, and easy installation. [Means for solving the problem]

[0006] To achieve the above and other related objects, the present invention provides a battery pack including: a case including a lower housing; a cell stack including a plurality of pouch-type battery cells and including two opposing tab sides and a side surface adjacent to the tab sides, the cell stack being installed within the lower housing; a thermally conductive structural adhesive that directly bonds and fixes the cell stack to a bottom plate of the lower housing; a foam adhesive that is filled between and connects the tab side of the cell stack to the lower housing; a battery management system; a flexible circuit board assembly including a flexible circuit board; side plates fixed to the side surfaces of the cell stack; and connection components that communicatively connect the battery management system to the flexible circuit board, the connection components including a flexible flat cable and an adapter sheet, the flexible flat cable being installed on the side surfaces of the cell stack and being connected and fixed to the side plates via the adapter sheet.

[0007] In one embodiment of the present invention, the number of the flexible flat cables is multiple and equal to the number of the flexible circuit boards, and at least some of the multiple flexible flat cables are installed overlapping each other and connected and fixed to the side panel via the same adapter sheet.

[0008] In one embodiment of the present invention, two adjacent layers of the flexible flat cable are fixed to each other with an adhesive.

[0009] In one embodiment of the present invention, the flexible flat cable is installed corresponding to a side surface of the cell stack, and the adapter sheet includes a first connection surface and a second connection surface, the first connection surface is fixedly connected to the side plate, and the second connection surface is fixedly connected to the flexible flat cable.

[0010] In one embodiment of the present invention, the first connection surface overlaps and connects with the side plate and is fixed to the side plate via a fastener, and the second connection surface is fixed to the flexible flat cable with an adhesive.

[0011] In one embodiment of the present invention, the connection component further includes a first connector, and the first connector is connected to both ends of the flexible flat cable, the first connector at one end of the flexible flat cable is connected to the flexible circuit board, and the first connector at the other end of the flexible flat cable is electrically connected to the battery management system.

[0012] In one embodiment of the present invention, the flexible circuit board assembly further includes a second connector, and the flexible circuit board is connected to the first connector via the second connector.

[0013] In one embodiment of the present invention, the flexible circuit board includes a flexible circuit board body, both ends of which are bent in the same direction to form fixing portions that are hooked onto the side panels, and the second connectors are installed on the fixing portions and connected to the corresponding first connectors.

[0014] In one embodiment of the present invention, one end of the flexible flat cable is connected to the second connector on the corresponding flexible circuit board, and the other end of the flexible flat cable extends to the battery management system. The multiple flexible flat cables are installed overlapping each other on the same path.

[0015] In one embodiment of the present invention, the first connectors on the plurality of flexible flat cables are arranged to be offset in the extension direction of the flexible flat cables.

[0016] In one embodiment of the present invention, the battery pack includes a first cell stack and a second cell stack, one tab side of the first cell stack faces one tab side of the second cell stack, the battery management system is located on another tab side of the first cell stack opposite the second cell stack, one ends of the multiple flexible flat cables are respectively connected to the corresponding flexible circuit boards, and the other ends of the multiple flexible flat cables extend across a side surface of the first cell stack and / or a side surface of the second cell stack and are electrically connected to the same battery management system. [Effects of the Invention]

[0017] The present invention provides a battery pack that achieves signal transmission by installing connecting components including a flexible flat cable within the battery pack, thereby avoiding the use of a low-voltage wiring harness assembly including components such as connectors, wires, terminals, and buckles, thereby reducing the volume and weight of the battery pack and improving its energy density. Installing multiple layers of flexible flat cables in layers does not occupy extra space in the battery pack, and fixing the flexible flat cables via an adapter sheet effectively fixes the flexible flat cables, thereby effectively preventing them from swinging during use, improving the space utilization rate and energy density of the battery pack, and making installation more convenient. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is an exploded view of a battery pack according to one embodiment of the present invention. [Figure 2] 1 is a structural schematic diagram of a flexible circuit board assembly in one embodiment of the present invention. [Figure 3] FIG. 1 is an exploded view of a flexible circuit board assembly in one embodiment of the present invention. [Figure 4] 1 is a schematic diagram of a mounting structure on one side of a flexible circuit board assembly in one embodiment of the present invention. [Figure 5] FIG. 10 is a schematic view of the mounting structure on the other side of the flexible circuit board assembly in one embodiment of the present invention. [Figure 6] FIG. 6 is a partial enlarged view of a connector on the flexible circuit board of FIG. 5 in one embodiment of the present invention. [Figure 7] 1 is a structural schematic diagram of a flexible circuit board assembly with a temperature sampling terminal in one embodiment of the present invention. [Figure 8] FIG. 2 is an exploded view of a flexible circuit board assembly with temperature sampling terminals in one embodiment of the present invention. [Figure 9] 1 is a schematic diagram of a mounting structure of a flexible circuit board assembly with a temperature sampling terminal in one embodiment of the present invention. [Figure 10] FIG. 10 is a partial enlarged view of a fixing structure portion of FIG. 9 in one embodiment of the present invention. [Figure 11] 1 is a schematic diagram of a mounting structure of a temperature sampling terminal in one embodiment of the present invention. [Figure 12] FIG. 2 is a structural schematic diagram of a flexible circuit board assembly in another embodiment of the present invention. [Figure 13] FIG. 10 is an exploded view of a flexible circuit board assembly in another embodiment of the present invention. [Figure 14] FIG. 10 is a schematic view of a mounting structure of a flexible circuit board assembly according to another embodiment of the present invention. [Figure 15] FIG. 10 is a plan view of a flexible circuit board assembly in another embodiment of the present invention. [Figure 16] 16 is a partially enlarged view of the mounting structure of the temperature sampling terminal of FIG. 15 according to another embodiment of the present invention. [Figure 17] 1 is a structural schematic diagram of a connecting component according to one embodiment of the present invention; [Figure 18] 1 is a schematic diagram of a mounting structure of a connecting part according to an embodiment of the present invention. [Figure 19] FIG. 2 is an exploded view of a connection piece in one embodiment of the present invention. [Figure 20] FIG. 2 is a plan view of a connection component according to one embodiment of the present invention. [Figure 21] 21 is an enlarged schematic view of a fixing portion of the adapter sheet of the connecting part of FIG. 20 in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, the embodiments of the present invention will be described with reference to specific examples. Those skilled in the art will easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied in other different specific embodiments, and the details of each item in this specification can be variously modified or changed based on different perspectives and applications without departing from the spirit of the present invention.

[0020] It should be noted that the drawings provided in this embodiment are merely a schematic method for explaining the basic concept of the present invention, and therefore only components related to the present invention are shown in the drawings, and are not drawn according to the number, shape, and dimensions of the components when actually implemented. When actually implemented, the shape, quantity, and ratio of each component may be changed arbitrarily, and the layout of the components may be more complicated.

[0021] In recent years, the development of new energy vehicles has been remarkable, and as their popularity has become increasingly high, the renewal of related components and technologies has also accelerated. Power battery systems are an important component of new energy vehicles, and under fierce market competition, the requirements for product performance, safety, and cost are also increasing. Power battery systems are an important component of new energy vehicles, and they mainly include a battery pack formed by connecting several cells in series and parallel, and can provide a power source for normal driving of the vehicle.

[0022] 1 , in one embodiment of the present invention, a battery pack includes a case, a cell stack 102, a thermally conductive structural adhesive, a foam adhesive 105, and a flexible circuit board assembly 200. The case includes a lower housing 101. The cell stack 102 includes a plurality of pouch-type battery cells and includes two opposing tab sides and a side surface adjacent to the tab sides. The cell stack 102 is installed in the lower housing 101, and the cell stack 102 and a bottom plate of the lower housing 101 are directly bonded and fixed with the thermally conductive structural adhesive. In other words, the cell stack 102 and the bottom plate of the lower housing 101 are directly bonded and fixed with the thermally conductive structural adhesive. The foam adhesive 105 is filled between and connects the tab side of the cell stack 102 and the lower housing 101. The flexible circuit board assembly 200 includes a flexible circuit board 201 and an insulating connection sheet. The flexible circuit board 201 is connected and fixed to the cell stack 102 via the insulating connection sheet. Here, the thickness and volume occupied by the insulating connection sheet are smaller than those of a conventional bracket for connecting and fixing the flexible circuit board 201. That is, the battery pack includes a lower housing 101 and a cell stack 102 installed in the lower housing 101, and the cell stack 102 is arranged in order within the lower housing 101. A chamber may be formed between the lower housing 101 and an upper cover 106 on top of the cell stack 102 to provide an enclosed storage space for the cell stack 102. Each cell stack 102 includes a plurality of pouch-type battery cells, and the plurality of pouch-type battery cells are stacked in order in the cell thickness direction to form the cell stack 102. When manufacturing a battery pack, the number of cell stacks 102 in each battery pack can be set according to user requirements. The higher the requirements for the power supply capacity of the battery pack, the more cell stacks 102 need to be installed in the lower housing 101.

[0023] Referring to FIG. 1 , in one embodiment of the present invention, two cell stacks 102, i.e., a first cell stack 1021 and a second cell stack 1022, are installed within a lower housing 101, with one tab side of the first cell stack 1021 facing one tab side of the second cell stack 1022. The two cell stacks 102 are separated by a case mid-beam 103. Foam adhesive 105 is installed on both sides of the cell stack 102 and is positioned between the cell stack 102 and the lower housing 101. Specifically, the foam adhesive 105 may be installed between one side of the cell stack 102 where the tab is installed and the side beam of the lower housing 101, and between one side of the cell stack 102 where the tab is installed and the case mid-beam 103. The cell stack 102 and the bottom plate of the lower housing 101 are directly bonded and fixed with a thermally conductive structural adhesive. Side plates 104 are further installed within the lower housing 101 on both sides of the cell stack 102. That is, the side plate 104 is located on a side surface of the cell stack 102, and this side surface is the side surface adjacent to the tab side of the cell stack 102. In other words, since the side plate 104 is located on a side surface of the cell stack 102 that is perpendicular to the case intermediate beam 103, the cell stack 102 can be compressed to a predetermined size by tightening the side plate 104 with a jig before being inserted into the lower housing 101.

[0024] 1 and 2, in one embodiment of the present invention, a flexible circuit board assembly 200 is further installed within the battery pack. The flexible circuit board assembly 200 includes a flexible circuit board 201, a sampling sheet 202, a second connector 203, and an insulating connecting sheet. In this embodiment, the insulating connecting sheet is a plastic sheet 204, and the flexible circuit board 201 is fixedly connected to the cell stack 102 via the insulating connecting sheet. Specifically, the plastic sheet 204 may be made of a material such as polyethylene terephthalate (PET) or polycarbonate (PC). Here, one flexible circuit board 201 is installed on each of the two tab sides of each cell stack 102, allowing real-time monitoring of information such as the voltage, temperature, and current output of the cell stack 102.

[0025] 2, 3, and 4, in one embodiment of the present invention, the flexible circuit board 201 is in the form of a bendable sheet, and includes a flexible circuit board body 2011. The flexible circuit board body 2011 can be positioned on the tab side of the cell stack 102, and the flexible circuit board body 2011 is attached to the tab side of the cell stack 102. In the present application, both ends of the flexible circuit board body 2011 are bent in the same direction, and fixing portions 2012 are formed on both ends of the flexible circuit board body 2011, and the fixing portions 2012 can be hooked onto the side panels 104. When attaching the flexible circuit board 201 to the cell stack 102, the flexible circuit board body 2011 is attached to the tab side close to the foam adhesive 105 of the cell stack 102, and the fixing portions 2012 on both ends of the flexible circuit board body 2011 are attached to the side surfaces close to the side panels 104 of the cell stack 102.

[0026] 2 , in one embodiment of the present invention, the insulating connection sheet includes a plastic sheet 204, and each flexible circuit board 201 is provided with a plurality of sampling sheets 202. The plurality of sampling sheets 202 are distributed along the stacking direction of the pouch-type battery cells and are welded in parallel to the flexible circuit board 201. The plurality of sampling sheets 202 are located on one side of the flexible circuit board body 2011, and the other side of the flexible circuit board body 2011 is adhered to the plastic sheet 204. That is, the flexible circuit board body 2011 is adhered and fixed to the plastic sheet 204, which is further adhered and fixed to the cell stack 102. The number of sampling sheets 202 is the same as the number of pouch-type battery cells in each cell stack 102, and when the flexible circuit board 201 is attached to the tab side of the cell stack 102, the sampling sheets 202 are welded and fixed to correspond to the tabs on the pouch-type battery cells. Here, the sampling sheet 202 can be made of metal, for example, nickel plate.

[0027] 2, 5, and 6, in one embodiment of the present invention, a second connector 203 is further provided on the fixing portion 2012 of the flexible circuit board 201. The flexible circuit board 201 is electrically connected to the battery management system 108 via the second connector 203 and a connecting wire, thereby realizing monitoring of the pouch-type battery cells. When the flexible circuit board 201 is attached to the tab side of the cell stack 102, the fixing portion 2012 of the flexible circuit board 201 is hooked onto the buckle 107 of the side plate 104. At this time, the second connector 203 on the fixing portion 2012 engages with the buckle 107 on the side plate 104, thereby limiting the position of the flexible circuit board 201.

[0028] 2 and 3 , in one embodiment of the present invention, plastic sheet 204 includes first fixing surface 2041 and second fixing surface 2042, which are connected to each other and are disposed at a predetermined angle. Plastic sheet 204 can be manufactured using plastic, and first fixing surface 2041 and second fixing surface 2042 are integrally molded. The angle between first fixing surface 2041 and second fixing surface 2042 is equal to the angle formed between the upper surface and the tab side surface of cell stack 102. During installation, first fixing surface 2041 is bonded to and connected with the upper surface of cell stack 102, and second fixing surface 2042 is bonded to and connected with flexible circuit board body 2011 attached to the tab side of cell stack 102, thereby ensuring that flexible circuit board body 2011 is fixed. In this embodiment, the first fixing surface 2041 and the second fixing surface 2042 are disposed, for example, at a right angle. Here, in this application, the upper surface of the cell stack 102 is the surface of the cell stack 102 that faces the upper cover 106.

[0029] 2 and 3 , in one embodiment of the present invention, a plurality of first openings 2043 are further formed on the first fixing surface 2041 of the plastic sheet 204. The plurality of first openings 2043 are arranged in parallel on the first fixing surface 2041, and the first openings 2043 are adjacent to the connection between the first fixing surface 2041 and the second fixing surface 2042. The number of the first openings 2043 is equal to the number of the sampling sheets 202, and the first openings 2043 are arranged corresponding to the sampling sheets 202. When welding the sampling sheets 202 and the tabs, a jig can enter through the first openings 2043. The present application does not limit the shape and size of the first openings 2043, as long as the first openings 2043 can prevent the jig from entering during welding. The first openings 2043 can be rectangular, circular, elliptical, or any other shape.

[0030] 3, in one embodiment of the present invention, adhesive (not shown) is provided on first fixing surface 2041 and second fixing surface 2042 and on the inside of the folded first fixing surface 2041 and second fixing surface 2042. The adhesive is a double-sided tape, and adhesively fixes first fixing surface 2041 of plastic sheet 204 to the upper surface of cell stack 102, and adhesively fixes second fixing surface 2042 of plastic sheet 204 to flexible circuit board 201.

[0031] 2 to 6, in one embodiment of the present invention, when the flexible circuit board assembly 200 is installed, a plurality of sampling sheets 202 are welded to one side of the flexible circuit board 201, a second connector 203 is assembled to the fixing portion 2012 of the flexible circuit board 201, and the second fixing surface 2042 of the plastic sheet 204 is fixed to the flexible circuit board body 2011 with an adhesive. After the assembly of the flexible circuit board assembly 200 is completed, the flexible circuit board assembly 200 is attached to the cell stack 102. Specifically, first, the first fixing surface 2041 of the plastic sheet 204 is fixed to the upper surface of the cell stack 102 with an adhesive. Then, the sampling sheets 202 are welded to the tabs of each pouch-type battery cell on the cell stack 102 through the first openings 2043. Finally, the fixing portion 2012 of the flexible circuit board 201 is attached through the openings in the side plate, and the second connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate.

[0032] 3 and 7 to 11, in one embodiment of the present invention, the battery pack further includes a temperature sampling terminal 205 and a fixing plate 207, and the temperature sampling terminal 205 is connected and fixed to the cell stack 102 via the fixing plate 207. A temperature sampling terminal 205 is further installed in the battery pack to collect the temperature of each pouch-type battery cell. The flexible circuit board body 2011 is located on the tab side of the cell stack 102, and the temperature sampling terminal 205 is located on the upper surface side of the cell stack 102, and the temperature sampling terminal 205 is electrically connected to the flexible circuit board 201. In this application, the flexible circuit board 201 further includes a plurality of extension structures 2013, which are connected to the flexible circuit board body 2011. That is, both ends of the extension structure 2013 are connected to the flexible circuit board body 2011 and the temperature sampling terminal 205, respectively. The location of the extension structure 2013 can be determined based on collection requirements and the overall structure of the battery pack. In this embodiment, the multiple stretching structures 2013 are arranged in parallel on a plane on which the first fixing surface 2041 of the plastic sheet 204 is located, or are arranged on the upper surface of the cell stack 102, and one end of the stretching structures 2013 is connected to the flexible circuit board body 2011, and the other end is connected to the temperature sampling terminal 205. In addition, the flexible circuit board assembly 200 further includes a reinforcing plate 206, a temperature sampling terminal 205, and a fixing plate 207, which can be pressed onto the stretching structures 2013 and / or the reinforcing plate 206 and attached to the upper surface of the cell stack 102.

[0033] 7 to 9, in one embodiment of the present invention, a temperature sampling terminal 205 is connected to the flexible circuit board 201 and is located at the other end of the extension structure 2013. The temperature sampling terminal 205 contacts the pouch-type battery cells in the cell stack 102 to collect the temperatures of the pouch-type battery cells and transmits the collected temperatures to the battery management system 108 via the flexible circuit board 201 to monitor the temperatures of the pouch-type battery cells and ensure the safe operation of the system.

[0034] 8 and 11 , in one embodiment of the present invention, a reinforcing plate 206 is installed on the stretched structure 2013 of the flexible circuit board 201. The reinforcing plate 206 is installed at one end of the stretched structure 2013, which is connected to the temperature sampling terminal 205. The reinforcing plate 206 and the temperature sampling terminal 205 are located on both sides of the stretched structure 2013, and the reinforcing plate 206 is close to the pouch-shaped battery cells. That is, the reinforcing plate 206 and the temperature sampling terminal 205 are located on opposite sides of the stretched structure 2013, and the reinforcing plate 206 faces the upper surface of the cell stack 102. Both ends of the reinforcing plate 206 extend outward from the temperature sampling terminal 205 to facilitate connection with the fixing plate 207.

[0035] 8, 9, and 10, in one embodiment of the present invention, a fixing plate 207 is installed on the upper surface of the cell stack 102 and is arranged along the thickness direction of the pouch-type battery cells. The fixing plate 207 is fixedly connected to the reinforcing plate 206 on one side of each temperature sampling terminal 205, thereby fixing the multiple temperature sampling terminals 205 to the fixing plate 207. Both ends of the fixing plate 207 are bent to the same side to form a curved structure 2071. When the fixing plate 207 is attached to the upper surface of the cell stack 102, the curved structure 2071 is bonded to both side surfaces of the cell stack 102. Because through holes are installed in the curved structure 2071, fixing structures 208 can be used to fixedly connect the fixing plate 207 to the side plates on both sides of the cell stack 102 to fix the multiple temperature sampling terminals 205. That is, both ends of the fixing plate 207 extend along the stacking direction of the pouch-type battery cells in the cell stack 102 and are connected and fixed to the corresponding side plates 104. Specifically, the curved structures 2071 are fixedly connected to the side plates 104. The fixing structures 208 are, for example, rivets or other fixing structures.

[0036] 8 and 9 , in one embodiment of the present invention, a plurality of second openings 2072 are provided in the fixing plate 207. The number of the second openings 2072 is the same as the number of the temperature sampling terminals 205, and the positions of the second openings 2072 are adapted to the positions of the temperature sampling terminals 205. When the fixing plate 207 is placed on the upper surface of the cell stack 102, the temperature sampling terminals 205 reach the surface of the fixing plate 207 by passing through the second openings 2072.

[0037] 8 to 11, in one embodiment of the present invention, an adhesive (not shown) is provided on the fixing plate 207. On the one hand, the adhesive on the fixing plate 207 can be fixedly connected to both sides of the reinforcing plate 206. That is, the fixing plate 207 can be pressed against the reinforcing plate 206 to fix the temperature sampling terminal 205 to the reinforcing plate 206, and the temperature sampling terminal 205 can reach the surface of the fixing plate 207 by passing through the second opening 2072 on the fixing plate 207. On the other hand, after the fixing plate 207 is fixedly connected to the temperature sampling terminal 205, the adhesive on the fixing plate 207 can be used to fix the fixing plate 207 to the pouch-type battery cell. That is, the fixing plate 207 can be attached to the upper surface of the cell stack 102.

[0038] 7 to 11, in one embodiment of the present invention, when installing the flexible circuit board assembly 200, the sampling sheet 202 and second connector 203 are first assembled to the flexible circuit board 201, and then the reinforcing plate 206 and the temperature sampling terminal 205 on the reinforcing plate 206 are assembled to the flexible circuit board 201. Then, the fixing plate 207 is fixedly connected to the reinforcing plate 206 with an adhesive, and finally, the flexible circuit board assembly 200 is attached to the cell stack 102. The fixing plate 207 can be fixed to the cell stack 102 with an adhesive, and the sampling sheet 202 can be welded to the tabs of each pouch-type battery cell on the cell stack 102. Finally, the fixing portion 2012 of the flexible circuit board 201 is engaged through the opening on the side plate 104, and the second connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate.

[0039] 12 to 16, another embodiment of the present invention provides another type of flexible circuit board assembly 200. The insulating connection sheet includes a thermocompression film 209. A sampling sheet 202 is fixed to a flexible circuit board 201. The thermocompression film 209 includes a first thermocompression film 2091 and a second thermocompression film 2092, and at least a portion of the flexible circuit board 201 and at least a portion of the sampling sheet 202 are pressed between the first thermocompression film 2091 and the second thermocompression film 2092, and the first thermocompression film 2091 and the second thermocompression film 2092 fix and insulate the flexible circuit board 201 and the sampling sheet 202.

[0040] 12 to 14, in another embodiment of the present invention, a flexible circuit board body 2011 is bonded to the upper surface of a cell stack 102. Both ends of the flexible circuit board body 2011 are bent in the same direction, and fixing portions 2012 are formed on both ends of the flexible circuit board body 2011. When attaching the flexible circuit board 201 to the cell stack 102, the flexible circuit board body 2011 is bonded to the upper surface of the cell stack 102, and the fixing portions 2012 on both ends of the flexible circuit board body 2011 are bonded to the side surfaces of the cell stack 102.

[0041] 12 and 13, in another embodiment of the present invention, a second connector 203 is further provided on the fixing portion 2012 of the flexible circuit board 201. The flexible circuit board 201 is electrically connected to the battery management system 108 via the second connector 203 and a connecting line, thereby realizing monitoring of the pouch-type battery cells. Also referring to FIG. 6, when the flexible circuit board 201 is attached to the upper surface of the cell stack 102, the fixing portion 2012 of the flexible circuit board 201 is hooked onto the buckle 107 of the side plate 104. At this time, the second connector 203 on the fixing portion 2012 engages with the buckle 107 on the side plate, thereby limiting the position of the flexible circuit board 201.

[0042] 12 to 14, in another embodiment of the present invention, each flexible circuit board 201 is provided with a plurality of sampling sheets 202, which are welded in parallel to the flexible circuit board main body 2011. The plurality of sampling sheets 202 are located on one side of the flexible circuit board main body 2011. In this embodiment, the flexible circuit board main body 2011 is located on the upper surface side of the cell stack 102, and one end of each sampling sheet 202 is fixedly connected to the flexible circuit board main body 2011, and the other end is bent in the same direction to form a vertical portion 2021. When the flexible circuit board main body 2011 is insulated and attached to the upper surface of the cell stack 102 via the thermocompression film 209, a portion of each sampling sheet 202 is insulated and attached to the upper surface of the cell stack 102 via the thermocompression film 209, and another portion is insulated and attached to the tab side of the cell stack 102 via the thermocompression film 209. The other end of the sampling sheet 202 is folded and extends to the position where the tab of the pouch-type battery cell is located. That is, the vertical portion 2021 extends toward the tab of the cell stack 102, and a portion of the vertical portion 2021 extends outside the first thermocompression film 2091 and the second thermocompression film 2092 and is welded and fixed to the tab of the corresponding pouch-type battery cell. The number of sampling sheets 202 is the same as the number of pouch-type battery cells in each cell stack 102, and when the flexible circuit board 201 is attached to the upper surface of the cell stack 102, the other end of the sampling sheet 202 corresponds to the tab on the pouch-type battery cell. The sampling sheet 202 is made of metal, for example, nickel plate.

[0043] 13 and 16 , in another embodiment of the present invention, each flexible circuit board 201 is provided with a plurality of first protrusions 2014. The first protrusions 2014 and the sampling sheet 202 are located on opposite sides of the flexible circuit board body 2011. Temperature sampling terminals 205 are attached to the first protrusions 2014, and the temperature of the pouch-type battery cells can be detected by attaching the temperature sampling terminals 205 to the first protrusions 2014. The number of first protrusions 2014 is the same as the number of temperature sampling terminals 205, and the positions of the first protrusions 2014 correspond to the positions of the temperature sampling terminals 205. That is, the temperature sampling terminals 205 are installed on the upper surface of the cell stack 102, and when the temperature sampling terminals 205 are attached to the first protrusions 2014, temperature sampling can be performed on the pouch-type battery cells that require sampling.

[0044] 13 and 16 , in another embodiment of the present invention, the shapes of the first thermocompression film 2091 and the second thermocompression film 2092 correspond to the shapes of the flexible circuit board 201 and the sampling sheet 202. In this embodiment, the first thermocompression film 2091 is disposed on the outer side of the vertical portion 2021 of the sampling sheet 202 and the flexible circuit board main body 2011, and the second thermocompression film 2092 is disposed on the inner side of the vertical portion 2021 of the sampling sheet 202 and the flexible circuit board main body 2011. The first thermocompression film 2091 and the second thermocompression film 2092 include a first thermocompression surface 2093 and a second thermocompression surface 2094. The first thermocompression surface 2093 and the second thermocompression surface 2094 are disposed at a predetermined angle, and the included angle between the first thermocompression surface 2093 and the second thermocompression surface 2094 is equal to the angle of the vertical portion 2021 on the sampling sheet 202 and the angle formed between the upper surface and the tab-side surface of the cell stack 102. When the first thermocompression film 2091 and the second thermocompression film 2092 are pressure-bonded to the flexible circuit board 201 and the sampling sheet 202, the edge of the first thermocompression surface 2093 overlaps the edge of the flexible circuit board main body 2011, and the edge of the second thermocompression surface 2094 exposes the other end of the sampling sheet 202. In addition, a plurality of second protrusions 2095 are formed on the first thermocompression film 2091 to protect the temperature sampling terminal 205. The second protrusions 2095 on the first thermocompression film 2091 correspond to the first protrusions 2014 on the flexible circuit board 201, and when the first thermocompression film 2091 is bonded to the flexible circuit board 201, the second protrusions 2095 on the first thermocompression film 2091 are bonded to the first protrusions 2014 on the flexible circuit board 201. In other words, when the first protrusions 2014 are pressed against the second protrusions 2095, the temperature sampling terminals 205 are attached to the upper surface of the cell stack 102, allowing temperature sampling to be performed on pouch-type battery cells that require sampling. In addition, the second protrusions 2095 have multiple through-holes that expose the temperature sampling terminals 205 attached to the first protrusions 2014.

[0045] 12 to 16, in another embodiment of the present invention, when installing a flexible circuit board assembly 200, multiple sampling sheets 202 are welded to one side of the flexible circuit board 201, and a second connector 203 is assembled on the fixing portion 2012 of the flexible circuit board 201. Then, a first thermocompression film 2091 and a second thermocompression film 2092 are pressed onto the flexible circuit board 201 and the sampling sheet 202. The sampling sheets 202 are then folded to form vertical portions 2021 on each sampling sheet 202. The thermocompression film 209 is then fixed to the upper surface of the cell stack 102 with an adhesive. The other end of the sampling sheet 202 exposed from the thermocompression film 209 is welded to the tab of each pouch-type battery cell on the cell stack 102. Finally, the fixing portion 2012 of the flexible circuit board 201 is attached through the opening in the side plate, and the second connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate.

[0046] 1 and 4 together with FIGS. 17 to 21, in one embodiment of the present invention, the battery pack further includes a connection component 300, a battery management system 108, and a side panel 104. The flexible circuit board 201 is communicatively connected to the battery management system 108 via the connection component 300, the side panel 104 is fixed to a side surface of the cell stack 102, and the connection component 300 is connected and fixed to the side panel 104. The connection component 300 includes a flexible flat cable 301 and an adapter sheet 303, and the flexible flat cable 301 is installed on the side surface of the cell stack 102 and connected and fixed to the side panel 104 via the adapter sheet 303. In other words, the flexible flat cable 301 is installed corresponding to the side surface of the cell stack 102. The connection component 300 is also provided, and one end of the connection component 300 is electrically connected to the second connector 203 of the flexible circuit board 201 and the other end is connected to the battery management system 108, thereby realizing signal transmission. Here, the connection part 300 includes a flexible flat cable 301 , a first connector 302 , and an adapter sheet 303 , and the flexible flat cable 301 is fixed to the side plate 104 via the adapter sheet 303 .

[0047] 4, 17, and 18, in one embodiment of the present invention, first connectors 302 are connected to both ends of a flexible flat cable 301. That is, the first connectors 302 are connected to both ends of the flexible flat cable 301, and the first connector 302 at one end of the flexible flat cable 301 is connected to the second connector 203 on the flexible circuit board 201, and the first connector 302 at the other end of the flexible flat cable 301 is electrically connected to the battery management system 108. In the present application, the number of flexible flat cables 301 may be plural, and the number of flexible flat cables 301 is equal to the number of flexible circuit boards 201. Here, the battery pack includes a first cell stack and a second cell stack, one tab side of the first cell stack facing one tab side of the second cell stack, and the battery management system 108 is located on another tab side of the first cell stack opposite the second cell stack. One end of each of the flexible flat cables 301 is connected to a corresponding flexible circuit board 201, and the other end of each of the flexible flat cables 301 extends across the side of the first cell stack and / or the side of the second cell stack and is electrically connected to the same battery management system 108. In this embodiment, if signals need to be transmitted between four flexible circuit boards 201 in each battery pack, for example, four flexible flat cables 301 are installed. The length and folding method of each flexible flat cable 301 can be adjusted as needed. Here, the first connectors 302 on the multiple flexible flat cables 301 are arranged offset in the extension direction of the flexible flat cables 301. In this embodiment, the flexible flat cable 301 is installed corresponding to the side surface of the cell stack 102 and extends along the side surface of the cell stack 102 from the second connector 203 on the flexible circuit board 201 to the battery management system 108. That is, one end of the flexible flat cable 301 is connected to the second connector 203 on the corresponding flexible circuit board 201, and the other end of the flexible flat cable 301 extends to the battery management system 108.Furthermore, multiple flexible flat cables 301 are installed in an overlapping manner on the overlapping paths. That is, at least a portion of the multiple flexible flat cables 301 are installed in an overlapping manner and are connected and fixed to the side panel 104 via the same adapter sheet 303. More specifically, the multiple flexible flat cables 301 are installed in an overlapping manner on the same path.

[0048] 17, 19, 20, and 21, in one embodiment of the present invention, the adapter sheet 303 includes a first connecting surface 3031 and a second connecting surface 3032, and the first connecting surface 3031 and the second connecting surface 3032 are disposed at a predetermined angle. During installation, the first connecting surface 3031 overlaps and connects with the side panel 104 and is fixed via a fastener 304. That is, the first connecting surface 3031 can be fixedly connected to the side panel 104. The second connecting surface 3032 is fixedly connected to the flexible flat cable 301 via an adhesive. That is, the second connecting surface 3032 can be fixedly connected to the flexible flat cable 301. In this embodiment, the first connecting surface 3031 and the second connecting surface 3032 are disposed at, for example, a right angle. The fastener 304 may be, for example, a fastener such as a rivet.

[0049] 1 and 17 to 21, in one embodiment of the present invention, when installing the connection component 300, first, the first connectors 302 at both ends of each flexible flat cable can be connected to the corresponding second connectors 203 and the battery management system. Next, multiple layers of flexible flat cables 301 are stacked and adjacent flexible flat cables 301 are fixed with adhesive. That is, two adjacent layers of flexible flat cables 301 can be fixed to each other with adhesive, thereby forming a single, multi-layered flexible flat cable 301. Finally, the adapter sheet 303 is installed, and the second connection surface 3032 of the adapter sheet 303 is fixed to the flexible flat cables 301 with adhesive. Then, the first connection surface 3031 of the adapter sheet 303 is stacked and connected to the side panel, and the first connection surface 3031 is fixed to the side panel 104 using a fastener or the like.

[0050] As described above, the present application provides a battery pack including a lower housing, cell stacks installed in the lower housing, flexible circuit boards installed on both sides of each cell stack, connecting components including a flexible flat cable, a plastic sheet or thermocompression film for fixing the flexible circuit boards, and a fixing plate for fixing a temperature sampling terminal. The battery pack provided by the present application does not require the installation of an independent bracket structure on the flexible circuit board or the like, thereby improving the volume utilization rate and energy density of the battery pack.

[0051] The above description merely describes preferred embodiments of the present application and the technical principles applied thereto. Those skilled in the art should understand that the scope of the present application is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but also includes other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features, such as, for example, technical solutions formed by mutually substituting the above-mentioned features and technical features having similar functions disclosed in the present application (but not limited to these), under circumstances that do not deviate from the concept of the invention.

[0052] Except for the technical features of the specification, other technical features are well-known technologies to those skilled in the art, so that the other technical features will not be described repeatedly here in order to highlight the innovative features of the present invention. [Industrial Applicability]

[0053] The battery pack of the present invention can be applied to the technical field of power batteries. [Explanation of symbols]

[0054] 101 Lower housing 102 Cell Stack 1021 First cell stack 1022 Second cell stack 103 Case intermediate beam 104 Side Panel 105 Foam adhesive 106 Upper cover 107 Buckle 108 Battery Management System 200 Flexible Circuit Board Assembly 201 Flexible Circuit Board 2011 Flexible circuit board body 2012 Fixed part 2013 Stretched structure 2014 1st protrusion 202 Sampling Sheet 2021 Vertical section 203 Second Connector 204 Plastic Sheet 2041 1st fixed surface 2042 2nd fixed surface 2043 First Opening 205 Temperature sampling terminal 206 Reinforcement plate 207 Fixed plate 2071 Curved Structure 2072 Second Opening 208 Fixed structure 209 Heat-sealed film 2091 First thermocompression film 2092 Second thermocompression film 2093 First thermocompression surface 2094 Second thermocompression surface 2095 2nd protrusion 300 connecting parts 301 Flexible Flat Cable 302 First Connector 303 Adapter seat 3031 First connecting surface 3032 Second connecting surface 304 Fixtures

Claims

1. a case including a lower housing; a cell stack including a plurality of pouch-shaped battery cells, the cell stack including two opposing tab sides and side surfaces adjacent to the tab sides, the cell stack being disposed within the lower housing; a thermally conductive structural adhesive that directly bonds and fixes the cell stack and the bottom plate of the lower housing; a foam adhesive filled between the tab side of the cell stack and the lower housing to connect them; a battery management system; a flexible circuit board assembly including a flexible circuit board; a side plate fixed to a side surface of the cell stack; a connection component communicatively connecting the battery management system to the flexible circuit board, the connection component including a flexible flat cable and an adapter sheet; Including, The battery pack is characterized in that the flexible flat cable is installed on a side surface of the cell stack and is connected and fixed to the side plate via the adapter sheet.

2. 2. The battery pack according to claim 1, wherein the number of the flexible flat cables is plural and equal to the number of the flexible circuit boards, and at least a portion of the flexible flat cables are installed overlapping each other and connected and fixed to the side plate via the same adapter sheet.

3. A battery pack as described in claim 2, wherein adjacent flexible flat cables are fixed to each other with adhesive, among multiple flexible flat cables that at least partially overlap each other.

4. 2. The battery pack of claim 1, wherein the flexible flat cable is installed corresponding to a side surface of the cell stack, the adapter sheet includes a first connection surface and a second connection surface, the first connection surface is fixedly connected to the side plate, and the second connection surface is fixedly connected to the flexible flat cable.

5. 5. The battery pack according to claim 4, wherein the first connection surface overlaps and connects with the side plate and is fixed to the side plate via a fastener, and the second connection surface is fixed to the flexible flat cable with an adhesive.

6. 3. The battery pack according to claim 2, wherein the connection component further includes a first connector, the first connectors being connected to both ends of the flexible flat cable, the first connector at one end of the flexible flat cable being connected to the flexible circuit board, and the first connector at the other end of the flexible flat cable being electrically connected to the battery management system.

7. 7. The battery pack according to claim 6, wherein the flexible circuit board assembly further includes a second connector, and the flexible circuit board is connected to the first connector via the second connector.

8. 8. The battery pack of claim 7, wherein the flexible circuit board includes a flexible circuit board body, both ends of which are bent in the same direction to form fixing portions that are hooked onto the side panels, and the second connectors are installed on the fixing portions and connected to the corresponding first connectors.

9. 8. The battery pack according to claim 7, wherein one end of the flexible flat cable is connected to the second connector on the corresponding flexible circuit board, the other end of the flexible flat cable extends to the battery management system, and a plurality of the flexible flat cables are installed overlapping each other along the same path.

10. 10. The battery pack according to claim 6, wherein the first connectors on the plurality of flexible flat cables are arranged offset in the extension direction of the flexible flat cables.

11. 3. The battery pack of claim 2, wherein the battery pack includes a first cell stack and a second cell stack, one tab side of the first cell stack faces one tab side of the second cell stack, the battery management system is located on another tab side of the first cell stack opposite the second cell stack, one ends of the flexible flat cables are connected to the corresponding flexible circuit boards, and the other ends of the flexible flat cables extend across a side surface of the first cell stack and / or a side surface of the second cell stack and are electrically connected to the same battery management system.

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