Battery pack

Abstract

To provide a battery pack that has a high spatial usage and high energy density, and that can be easily attached by changing a structure inside the battery pack.SOLUTION: A battery pack of the present invention 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 foamed adhesive connected by filling a space between the tab side of the cell stack and the lower part housing, side plates fixed at the side surfaces of the cell stack, a flexible circuit board assembly including a flexible circuit board and an insulating connecting sheet, in which the flexible circuit board is connected and fixed to the cell stack through the insulating connecting sheet, a battery management system, and a connection component connected by communication between the battery management system and the flexible circuit board and including a connection component connected and fixed to the side plate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the technical field of power batteries, and particularly to battery packs.

Background Art

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

[0003] In the field of power batteries used in electric vehicles, in order to improve the full-charge driving range and charging speed of electric vehicles, it is necessary to further enhance the energy density and cooling performance of the battery pack. As one method of improving the energy density, the CTP (cell to pack) type battery pack omits the step of forming a battery module from cells and integrates the cells directly into the battery pack, so that the structural parts and electrical connection parts required for the formation of the battery module can be omitted, and thus the space used for the cells themselves can be increased.

[0004] Currently, common cells are classified into cylindrical cells, prismatic cells, and pouch-type battery cells based on structural differences. While CTP (Computer-to-Plate) battery packs using prismatic cells are already widely used, pouch-type battery cells still face a number of problems in the process of integrating them into CTP battery packs due to their vulnerability to external shocks and difficulty in assembly. With existing technology, it is difficult to directly mount stacks of pouch-type battery cells into the battery pack, and the low space utilization rate leads to a decrease in the energy density of the battery pack. [Overview of the project] [Problems that the invention aims to solve]

[0005] Taking into consideration the shortcomings of the existing technologies described above, the present invention aims to provide a battery pack that has high space utilization efficiency, high energy density, and can be easily installed. [Means for solving the problem]

[0006] To achieve the above and other related objectives, the present invention provides a battery pack comprising: a case including a lower housing; a cell stack installed in the lower housing, comprising a plurality of pouch-type battery cells and comprising two opposing tab sides and sides adjacent to the tab sides; a foam adhesive filled and connected between the tab sides of the cell stack and the lower housing; a side plate fixed to the sides of the cell stack; a flexible circuit board assembly comprising a flexible circuit board and an insulating connection sheet, wherein the flexible circuit board is connected and fixed to the cell stack via the insulating connection sheet; a battery management system; and a connecting component that is communicated between the battery management system and the flexible circuit board and is connected and fixed to the side plate.

[0007] In one embodiment of the present invention, the flexible circuit board includes a flexible circuit board body, and the flexible circuit board body is provided with a plurality of sampling sheets distributed along the stacking direction of the pouch-type battery cells, and the sampling sheets are welded and fixed to the tabs of the corresponding pouch-type battery cells.

[0008] In one embodiment of the present invention, the insulating connecting sheet includes a plastic sheet.

[0009] In one embodiment of the present invention, the flexible circuit board body is located on the tab side of the cell stack. The plastic sheet includes a first fixed surface and a second fixed surface connected to each other, the second fixed surface being bonded to and connected to the flexible circuit board body, and the first fixed surface being bonded to and connected to the upper surface of the cell stack to fix the flexible circuit board body.

[0010] In one embodiment of the present invention, a plurality of first openings are provided on the first fixed surface, and the first openings are located close to the connection between the first fixed surface and the second fixed surface and correspond to the sampling sheet.

[0011] In one embodiment of the present invention, the flexible circuit board body is adhesively fixed to the plastic sheet, and the plastic sheet is adhesively fixed to the cell stack.

[0012] In one embodiment of the present invention, the flexible circuit board assembly further includes a first connector, wherein both ends of the flexible circuit board body are bent in the same direction to form a fixing portion that hooks onto the side plate, and the first connector is mounted on the fixing portion and electrically connected to the battery management system via the connecting component.

[0013] In one embodiment of the present invention, the invention further includes a temperature sampling terminal and a fixing plate, wherein the temperature sampling terminal is connected to and fixed to the cell stack via the fixing plate.

[0014] In one embodiment of the present invention, both ends of the fixing plate extend along the stacking direction of the pouch-type battery cells in the cell stack and are connected and fixed to the corresponding side plates.

[0015] In one embodiment of the present invention, the flexible circuit board body is located on the tab side of the cell stack, and the temperature sampling terminal is located on the upper surface side of the cell stack. The flexible circuit board further includes a plurality of stretched structures, the ends of which are connected to the flexible circuit board body and the temperature sampling terminal, respectively.

[0016] In one embodiment of the present invention, a reinforcing plate is provided at one end of the stretched structure connected to the temperature sampling terminal, the reinforcing plate and the temperature sampling terminal are located on opposite sides of the stretched structure, and the reinforcing plate faces the upper surface of the cell stack. A second opening corresponding to the temperature sampling terminal is provided in the fixing plate, and the fixing plate is pressed against the stretched structure and / or the reinforcing plate and bonded to the upper surface of the cell stack.

[0017] In one embodiment of the present invention, both ends of the fixing plate are bent in the same direction to form a curved structure, and the curved structure is fixedly connected to the side plate.

[0018] In one embodiment of the present invention, the connecting component includes a flexible flat cable and an adapter sheet, the flexible flat cable being installed on the side of the cell stack and connected and fixed to the side plate via the adapter sheet.

[0019] In one embodiment of the present invention, the number of flexible flat cables is multiple, equal to the number of flexible circuit boards, and at least some of the multiple flexible flat cables are installed overlapping and connected to the side plate via the same adapter sheet.

[0020] In one embodiment of the present invention, two adjacent layers of the flexible flat cable are fixed to each other with an adhesive.

[0021] In one embodiment of the present invention, the flexible flat cable is installed corresponding to the side of the cell stack. The adapter sheet includes a first connection surface and a second connection surface, the first connection surface being fixedly connected to the side plate and the second connection surface being fixedly connected to the flexible flat cable.

[0022] In one embodiment of the present invention, the first connecting surface is superimposed on the side plate and fixed to the side plate via a fastener. The second connecting surface is fixed to the flexible flat cable with adhesive.

[0023] In one embodiment of the present invention, one end of the flexible flat cable is connected to 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 along the same path.

[0024] In one embodiment of the present invention, the battery pack includes a first cell stack and a second cell stack, wherein one tab side of the first cell stack faces one tab side of the second cell stack, the battery management system is located on the other tab side of the first cell stack opposite to the second cell stack, one end of each of the flexible flat cables is connected to the corresponding flexible circuit board, and the other ends of the flexible flat cables extend across the sides of the first cell stack and / or the sides of the second cell stack and are electrically connected to the same battery management system.

[0025] In one embodiment of the present invention, the cell stack and the bottom plate of the lower housing are directly bonded and fixed together with a thermally conductive structural adhesive.

Advantages of the Invention

[0026] The present invention provides a battery pack that realizes signal transmission by installing a connecting component including a flexible flat cable in the battery pack, and can avoid the use of a low-voltage wiring harness assembly including components such as connectors, wires, terminals, and buckles. Therefore, the volume of the battery pack can be reduced, the weight can be lightened, and the energy density can be improved. By stacking and installing multiple layers of flexible flat cables, the extra space of the battery pack is not occupied, and by fixing the flexible flat cable through an adapter sheet, the flexible flat cable can be effectively fixed, so that it can be effectively prevented from swaying during use, improving the space utilization rate and energy density of the battery pack, and making the installation more convenient.

[0027] The present invention proposes a battery pack that can prevent the flexible circuit board from swaying greatly during use by installing a plastic sheet to fix and position the flexible circuit board assembly. Compared with the method of using plastic brackets or the upper and lower covers of modules for fixing, the plastic sheet can not only play a role in positioning and fixing the flexible circuit board, but also the plastic sheet is relatively inexpensive, easy to process, lightweight, and can save material costs. Therefore, the cost of the battery pack can be reduced, the space utilization rate can be improved, the energy density can be increased, and furthermore, the assembly process can be simplified, and the welding jig for tabs can be avoided by the opening of the fixing sheet.

[0028] The present invention presents a battery pack that installs a fixing plate to fix temperature sampling terminals. When installing the sensors, since the temperature sampling terminals can be installed one by one and the fixing plate can be directly installed, the process can be simplified. Moreover, the fixing plate can ensure that the positions of the temperature sampling terminals are more accurate, improve the sampling accuracy, and further ensure that the temperature sampling terminals do not shift during use.

Brief Description of the Drawings

[0029] [Figure 1] It is an exploded view of the battery pack in one embodiment of the present invention. [Figure 2] It is a schematic structural view of a flexible circuit board assembly in one embodiment of the present invention. [Figure 3] It is an exploded view of the flexible circuit board assembly in one embodiment of the present invention. [Figure 4] It is a schematic view of the mounting structure on one side of the flexible circuit board assembly in one embodiment of the present invention. [Figure 5] It 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] It is a partially enlarged view of the connector on the flexible circuit board in FIG. 5 in one embodiment of the present invention. [Figure 7] It is a schematic structural view of a flexible circuit board assembly provided with temperature sampling terminals in one embodiment of the present invention. [Figure 8] It is an exploded view of the flexible circuit board assembly provided with temperature sampling terminals in one embodiment of the present invention. [Figure 9] It is a schematic view of the mounting structure of the flexible circuit board assembly provided with temperature sampling terminals in one embodiment of the present invention. [Figure 10] It is a partially enlarged view of the fixing structure part in FIG. 9 in one embodiment of the present invention. [Figure 11]This is a schematic diagram of the mounting structure for a temperature sampling terminal in one embodiment of the present invention. [Figure 12] This is a schematic diagram of the structure of a flexible circuit board assembly in another embodiment of the present invention. [Figure 13] This is an exploded view of a flexible circuit board assembly in another embodiment of the present invention. [Figure 14] This is a schematic diagram of the mounting structure of a flexible circuit board assembly in another embodiment of the present invention. [Figure 15] This is a plan view of a flexible circuit board assembly in another embodiment of the present invention. [Figure 16] This is a partially enlarged view of the mounting structure of the temperature sampling terminal in Figure 15, in another embodiment of the present invention. [Figure 17] This is a schematic diagram of the structure of a connecting component in one embodiment of the present invention. [Figure 18] This is a schematic diagram of the mounting structure of a connecting component in one embodiment of the present invention. [Figure 19] This is an exploded view of a connecting component in one embodiment of the present invention. [Figure 20] This is a plan view of a connecting component in one embodiment of the present invention. [Figure 21] This is an enlarged schematic diagram of the fixing portion of the adapter sheet of the connecting component in Figure 20 in one embodiment of the present invention. [Modes for carrying out the invention]

[0030] Embodiments of the present invention will be described below with reference to specific examples. Those skilled in the art will readily understand other advantages and effects of the present invention from the disclosures herein. The present invention can also be implemented or applied by other different specific embodiments, and the details of each item herein can be modified or changed in various ways based on different viewpoints and applications, without departing from the spirit of the invention.

[0031] It should be noted that the drawings provided in this embodiment are merely schematic representations for illustrating the basic concepts of the present invention. Therefore, only the parts relevant to the present invention are shown in the drawings, and they do not depict the number, shape, and dimensions of the parts as they would appear in actual implementation. In actual implementation, the form, quantity, and proportion of each part may be arbitrarily changed, and the layout of the parts may become more complex.

[0032] In recent years, the development of new energy vehicles has been remarkable, and their adoption rate has increased significantly, accelerating the renewal of related parts and technologies. The power battery system is a crucial component of new energy vehicles, and under fierce market competition, the demands on product performance, safety, and cost are constantly rising. The power battery system, a key component of new energy vehicles, mainly consists of a battery pack formed by connecting several cells in series and parallel, and can provide a power source for the normal operation of a vehicle.

[0033] Referring to Figure 1, in one embodiment of the present invention, the battery pack comprises a case, a cell stack 102, a thermally conductive structural adhesive, a foam adhesive 105, and a flexible circuit board assembly 200, wherein the case comprises a lower housing 101, the cell stack 102 comprises a plurality of pouch-type battery cells and comprises two opposing tab sides and sides adjacent to the tab sides, the cell stack 102 is installed within the lower housing 101, and the cell stack 102 and the bottom plate of the lower housing 101 are directly bonded and fixed together 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 together with the thermally conductive structural adhesive. The foam adhesive 105 fills and connects the tab sides of the cell stack 102 and the lower housing 101, and the flexible circuit board assembly 200 comprises 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 conventional brackets for connecting and fixing the flexible circuit board 201. In other words, the battery pack includes a lower housing 101 and a cell stack 102 installed within the lower housing 101, with the cell stack 102 arranged sequentially within the lower housing 101. A chamber may be formed between the lower housing 101 and an upper cover 106 located above the cell stack 102 to provide a closed housing space for the cell stack 102. Each cell stack 102 includes a plurality of pouch-type battery cells, which are stacked sequentially in the thickness direction of the cells to form the cell stack 102. When manufacturing the battery pack, the number of cell stacks 102 in each battery pack can be set according to the user's requirements, and the higher the requirement for the power supply capacity of the battery pack, the more correspondingly larger the number of cell stacks 102 that need to be installed within the lower housing 101.

[0034] Referring to Figure 1, in one embodiment of the present invention, two cell stacks 102, namely 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 using a case intermediate beam 103. Foam adhesive 105 is installed on both sides of the cell stacks 102 and is located between the cell stacks 102 and the lower housing 101. Specifically, the foam adhesive 105 can be installed between one side of the cell stack 102 where the tabs are installed and the side beam of the lower housing 101, and between one side of the cell stack 102 where the tabs are installed and the case intermediate beam 103. The cell stacks 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 inside the lower housing 101 and on both sides of the cell stacks 102. In other words, the side plate 104 is located on the side of the cell stack 102, and this side is adjacent to the tab side of the cell stack 102. To put it another way, the side plate 104 is installed on both sides of the cell stack 102 along the stacking direction of the pouch-type battery cells inside the cell stack 102. To put it another way, since the side plate 104 is located on the side of the cell stack 102 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.

[0035] Referring to Figures 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 including a flexible circuit board 201, a sampling sheet 202, a first connector 203, and an insulating connection sheet. In this embodiment, the insulating connection sheet is a plastic sheet 204, and the flexible circuit board 201 is fixedly connected to the cell stack 102 via the insulating connection sheet. Specifically, the plastic sheet 204 can be made of a material such as polyethylene glycol 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.

[0036] Referring to Figures 2, 3, and 4, in one embodiment of the present invention, the flexible circuit board 201 is a bendable sheet and includes a flexible circuit board body 2011 which can be positioned on the tab side of the cell stack 102 and is bonded to the tab side of the cell stack 102. In this application, both ends of the flexible circuit board body 2011 are bent in the same direction and fixing portions 2012 are formed at both ends of the flexible circuit board body 2011 which can be hooked onto the side plate 104. When the flexible circuit board 201 is attached to the cell stack 102, the flexible circuit board body 2011 is bonded to the tab side of the cell stack 102 that is close to the foam adhesive 105 and the fixing portions 2012 at both ends of the flexible circuit board body 2011 correspond to the sides of the cell stack 102 that are close to the side plate 104.

[0037] Referring to Figure 2, in one embodiment of the present invention, the insulating connection sheet includes a plastic sheet 204, and each flexible circuit board 201 is fitted with a plurality of sampling sheets 202, which are distributed along the stacking direction of the pouch-type battery cells, and the plurality of sampling sheets 202 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 bonded to the plastic sheet 204. In other words, the flexible circuit board body 2011 is bonded and fixed to the plastic sheet 204, and the plastic sheet 204 is further bonded 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 corresponding to the tabs on the pouch-type battery cells. Here, the sampling sheet 202 can be made from metal, for example, a nickel plate.

[0038] Referring to Figures 2, 5, and 6, in one embodiment of the present invention, a first connector 203 is further installed 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 first connector 203 and connecting components. This enables monitoring of 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 hooks onto the buckle 107 of the side plate 104. At this time, the first 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.

[0039] Referring to Figures 2 and 3, in one embodiment of the present invention, the plastic sheet 204 includes a first fixing surface 2041 and a second fixing surface 2042, the first fixing surface 2041 and the second fixing surface 2042 being connected to each other and positioned at a predetermined angle. The plastic sheet 204 can be manufactured using plastic, and the first fixing surface 2041 and the second fixing surface 2042 are integrally molded. The angle between the first fixing surface 2041 and the second fixing surface 2042 is equal to the angle formed between the upper surface and the tab-side surface of the cell stack 102. During installation, it can be ensured that the first fixing surface 2041 is bonded to the upper surface of the cell stack 102, and the second fixing surface 2042 is bonded to the flexible circuit board body 2011 attached to the tab side of the cell stack 102, thereby securing the flexible circuit board body 2011. In this embodiment, the first fixed surface 2041 and the second fixed surface 2042 are installed, for example, at right angles. Here, in this application, the upper surface of the cell stack 102 is the side surface of the cell stack 102 facing the upper cover 106.

[0040] Referring to Figures 2 and 3, in one embodiment of the present invention, the first fixed surface 2041 of the plastic sheet 204 is further provided with a plurality of first openings 2043. The plurality of first openings 2043 are arranged in parallel on the first fixed surface 2041 and are close to the connection between the first fixed surface 2041 and the second fixed surface 2042. The number of first openings 2043 is equal to the number of sampling sheets 202 and the first openings 2043 are installed corresponding to the sampling sheets 202. When welding the sampling sheets 202 to the tabs, the jig can enter through the first openings 2043. The present application does not limit the shape and dimensions of the first openings 2043, but the first openings 2043 only need to be able to prevent the jig from entering during welding. The first openings 2043 can be rectangular, circular, elliptical, or any other shape.

[0041] Referring to Figure 3, in one embodiment of the present invention, an adhesive (not shown) is applied to the first fixing surface 2041 and the second fixing surface 2042, and to the inside of the folded surfaces of the first and second fixing surfaces 2041 and 2042. The adhesive is a double-sided tape that adheres the first fixing surface 2041 of the plastic sheet 204 to the upper surface of the cell stack 102 and adheres the second fixing surface 2042 of the plastic sheet 204 to the flexible circuit board 201.

[0042] Referring to Figures 2 to 6, in one embodiment of the present invention, when mounting the flexible circuit board assembly 200, a plurality of sampling sheets 202 are welded to one side of the flexible circuit board 201, a first 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 adhesive. After the assembly of the flexible circuit board assembly 200 is complete, 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 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 opening 2043. Finally, the fixing portion 2012 of the flexible circuit board 201 is engaged through the opening on the side plate, and the first connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate.

[0043] Referring to Figures 3, 7-11, in one embodiment of the present invention, the battery pack further includes a temperature sampling terminal 205 and a fixing plate 207, the temperature sampling terminal 205 being connected to and fixed to the cell stack 102 via the fixing plate 207. A temperature sampling terminal 205 is also installed within 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, 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 stretched structures 2013, the plurality of stretched structures 2013 being connected to the flexible circuit board body 2011. That is, both ends of the stretched structures 2013 are connected to the flexible circuit board body 2011 and the temperature sampling terminal 205, respectively. The position of the stretched structures 2013 can be limited based on the collection requirements and the overall structure of the battery pack. In this embodiment, the multiple stretched structures 2013 are installed in parallel on a plane having a first fixed surface 2041 of the plastic sheet 204, or installed on the upper surface of the cell stack 102, with one end of each stretched structure 2013 connected to the flexible circuit board body 2011 and the other end connected to the temperature sampling terminal 205. Furthermore, a reinforcing plate 206, a temperature sampling terminal 205, and a fixing plate 207 are installed within the flexible circuit board assembly 200, and the fixing plate 207 can be pressed against the stretched structures 2013 and / or the reinforcing plate 206 and bonded to the upper surface of the cell stack 102.

[0044] Referring to Figures 7 to 9, in one embodiment of the present invention, the temperature sampling terminal 205 is connected to the flexible circuit board 201 and located at the other end of the stretched structure 2013. The temperature sampling terminal 205 contacts the pouch-type battery cells in the cell stack 102 to collect the temperature of the pouch-type battery cells and transmits it to the battery management system 108 via the flexible circuit board 201 to enable temperature monitoring of the pouch-type battery cells and ensure the safe operation of the system.

[0045] Referring to Figures 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 that is connected to a temperature sampling terminal 205. 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 is close to the pouch-type battery cell. In other words, 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 fixed plate 207.

[0046] Referring to Figures 8, 9, and 10, in one embodiment of the present invention, the fixing plate 207 is installed on the upper surface of the cell stack 102 and is positioned along the thickness direction of the pouch-type battery cells. The fixing plate 207 is fixedly connected to a reinforcing plate 206 on one side of each temperature sampling terminal 205, thereby fixing 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 corresponds to both sides of the cell stack 102. Through holes are provided in the curved structure 2071 so that the fixing plate 207 can be fixedly connected to the side plates on both sides of the cell stack 102 using a fixing structure 208, thereby fixing multiple temperature sampling terminals 205. In other words, 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 structure 2071 is fixedly connected to the side plate 104. The fixing structure 208 is, for example, a rivet or other fixing structure.

[0047] Referring to Figures 8 and 9, in one embodiment of the present invention, a plurality of second openings 2072 are installed on the fixed plate 207. The number of second openings 2072 is the same as the number of temperature sampling terminals 205, and the positions of the second openings 2072 correspond to the positions of the temperature sampling terminals 205. When the fixed plate 207 is placed on the upper surface of the cell stack 102, the temperature sampling terminals 205 penetrate the second openings 2072 and reach the surface of the fixed plate 207.

[0048] Referring to Figures 8 to 11, in one embodiment of the present invention, an adhesive (not shown) is applied to 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 cell stack 102, 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 fixing the fixing plate 207 to the temperature sampling terminal 205, the adhesive on the fixing plate 207 can be used to fix it to the pouch-type battery cell. That is, the fixing plate 207 can be bonded to the upper surface of the cell stack 102.

[0049] Referring to Figures 7 to 11, in one embodiment of the present invention, when mounting the flexible circuit board assembly 200, the sampling sheet 202 and the first connector 203 are assembled with the flexible circuit board 201, and then the reinforcing plate 206 and the temperature sampling terminal 205 on the reinforcing plate 206 are assembled with the flexible circuit board 201. Then, the fixing plate 207 is fixed to the reinforcing plate 206 with adhesive, and finally, the flexible circuit board assembly 200 is mounted to the cell stack 102. The fixing plate 207 can be fixed to the cell stack 102 via 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 first connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate.

[0050] Referring to Figures 12 to 16, another embodiment of the present invention further provides another type of flexible circuit board assembly 200. The insulating connection sheet includes a thermocompression film 209. The sampling sheet 202 is fixed to the flexible circuit board 201. The thermocompression film 209 includes a first thermocompression film 2091 and a second thermocompression film 2092, which press at least a portion of the flexible circuit board 201 and at least a portion of the sampling sheet 202 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.

[0051] Referring to Figures 12 to 14, in another embodiment of the present invention, the flexible circuit board body 2011 is bonded to the upper surface of the cell stack 102. Both ends of the flexible circuit board body 2011 are bent in the same direction, and fixing portions 2012 are formed at both ends of the flexible circuit board body 2011. When the flexible circuit board 201 is attached 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 at both ends of the flexible circuit board body 2011 correspond to the sides of the cell stack 102.

[0052] Referring to Figures 12 and 13, in another embodiment of the present invention, a first connector 203 is further installed 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 first connector 203 and the connecting component 300. This enables monitoring of pouch-type battery cells. Referring also to Figure 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 hooks onto the buckle 107 of the side plate 104. At this time, the first 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.

[0053] Referring to Figures 12 to 14, in another embodiment of the present invention, a plurality of sampling sheets 202 are installed on each flexible circuit board 201, and the plurality of sampling sheets 202 are welded in parallel to the flexible circuit board body 2011. The plurality of sampling sheets 202 are located on one side of the flexible circuit board body 2011. In this embodiment, the flexible circuit board body 2011 is located on the upper surface side of the cell stack 102, one end of each sampling sheet 202 is fixedly connected to the flexible circuit board body 2011, and the other end is bent in the same direction to form a vertical portion 2021. When the flexible circuit board body 2011 is bonded to the upper surface of the cell stack 102 insulated via the thermocompression film 209, a portion of each sampling sheet 202 is bonded to the upper surface of the cell stack 102 insulated via the thermocompression film 209, and another portion is bonded to the tab side of the cell stack 102 insulated via the thermocompression film 209. The other end of the sampling sheet 202 is folded and extended to the position of the tab on the pouch-type battery cell. That is, the vertical portion 2021 extends toward the tab side of the cell stack 102, and a portion of the vertical portion 2021 extends beyond 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 quantity 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, a nickel plate.

[0054] Referring to Figures 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 by installing the temperature sampling terminals 205 on the first protrusions 2014, the temperature of the pouch-type battery cells can be detected. 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 are installed corresponding to the positions of the temperature sampling terminals 205. In other words, 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 pouch-type battery cells that require sampling.

[0055] Referring to Figures 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 installed on the outside of the vertical portion 2021 of the sampling sheet 202 and the flexible circuit board body 2011, and the second thermocompression film 2092 is installed on the inside of the vertical portion 2021 of the sampling sheet 202 and the flexible circuit board 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 set at a preset angle, and the 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 pressed against the flexible circuit board 201 and the sampling sheet 202, the edge of the first thermocompression surface 2093 overlaps with the edge of the flexible circuit board body 2011, and the edge of the second thermocompression surface 2094 exposes the other end of the sampling sheet 202. In addition, multiple second protrusions 2095 are provided on the first thermocompression film 2091 to protect the temperature sampling terminal 205. The second projection 2095 on the first thermocompression film 2091 corresponds to the first projection 2014 on the flexible circuit board 201. When the first thermocompression film 2091 is bonded to the flexible circuit board 201, the second projection 2095 on the first thermocompression film 2091 is bonded to the first projection 2014 on the flexible circuit board 201. In other words, by pressurizing the first projection 2014 against the second projection 2095, the temperature sampling terminal 205 is installed on the upper surface of the cell stack 102, enabling temperature sampling of pouch-type battery cells that require sampling. In addition, multiple through-holes are provided on the second projection 2095, and these through-holes expose the temperature sampling terminal 205 installed on the first projection 2014.

[0056] Referring to Figures 12 to 16, in another embodiment of the present invention, when mounting the flexible circuit board assembly 200, a plurality of sampling sheets 202 are welded to one side of the flexible circuit board 201, the first connector 203 is assembled on the fixing portion 2012 of the flexible circuit board 201, and then the first thermocompression film 2091 and the second thermocompression film 2092 are pressed against the flexible circuit board 201 and the sampling sheets 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 via 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 engaged through an opening on the side plate, and the first connector 203 on the fixing portion 2012 is engaged with the buckle 107 on the side plate. In this embodiment, by limiting the positions of the flexible circuit board 201 and sampling sheet 202 with a thermocompression film 209, the conventional plastic brackets and upper and lower covers of the module of the battery pack can be omitted, significantly reducing costs. At the same time, because it serves to fix and insulate the flexible circuit board 201 and sampling sheet 202, the assembly process during installation can be simplified. Furthermore, since the temperature sampling terminals 205 are all positioned via the thermocompression film 209, positional accuracy can be guaranteed, and manual alignment by assembly workers is not required.

[0057] Referring together with Figures 17 to 21, and Figures 1 and 4, in one embodiment of the present invention, the battery pack further includes a connector 300, a battery management system 108, and a side plate 104. The flexible circuit board 201 is communicated to the battery management system 108 via the connector 300, the side plate 104 is fixed to the side of the cell stack 102, and the connector 300 is connected and fixed to the side plate 104. The connector 300 includes a flexible flat cable 301 and an adapter sheet 303, the flexible flat cable 301 is installed on the side of the cell stack 102 and connected and fixed to the side plate 104 via the adapter sheet 303. In other words, the flexible flat cable 301 is installed corresponding to the side of the cell stack 102. The connector 300 is also provided, one end of which is electrically connected to a first connector 203 of the flexible circuit board 201, and the other end is connected to the battery management system 108, thereby enabling signal transmission. Here, the connecting component 300 includes a flexible flat cable 301, a second connector 302, and an adapter sheet 303, the flexible flat cable 301 being fixed to the side plate 104 via the adapter sheet 303.

[0058] Referring to Figures 4, 17, and 18, in one embodiment of the present invention, second connectors 302 are connected to both ends of a flexible flat cable 301. That is, second connectors 302 are connected to both ends of the flexible flat cable 301, the second connector 302 at one end of the flexible flat cable 301 is connected to a first connector 203 on a flexible circuit board 201, and the second connector 302 at the other end of the flexible flat cable 301 is electrically connected to a battery management system 108. In this application, the number of flexible flat cables 301 may be multiple, 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, where one tab side of the first cell stack faces one tab side of the second cell stack, and the battery management system 108 is located on the other tab side of the first cell stack opposite to the second cell stack, with one end of each of the multiple flexible flat cables 301 connected to the corresponding flexible circuit board 201, and the other ends of the multiple flexible flat cables 301 extending across the sides of the first cell stack and / or the second cell stack and electrically connected to the same battery management system 108. In this embodiment, if it is necessary to transmit signals from 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 may be adjusted as needed. Here, the second connectors 302 on the multiple flexible flat cables 301 are positioned offset in the direction of extension of the flexible flat cables 301. In this embodiment, the flexible flat cable 301 is installed corresponding to the side of the cell stack 102 and extends along the side of the cell stack 102 from the first connector 203 on the flexible circuit board 201 to the battery management system 108. In other words, one end of the flexible flat cable 301 is connected to the corresponding first connector 203 on the 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 overlapping along overlapping paths. In other words, at least some of the multiple flexible flat cables 301 are installed overlapping and connected and fixed to the side plate 104 via the same adapter sheet 303. Specifically, multiple flexible flat cables 301 are installed overlapping along the same path.

[0059] Referring to Figures 17, 19, 20, and 21, in one embodiment of the present invention, the adapter sheet 303 includes a first connection surface 3031 and a second connection surface 3032, and the first connection surface 3031 and the second connection surface 3032 are set at a predetermined angle. During installation, the first connection surface 3031 overlaps with the side plate 104 and is fixed via a fastener 304. In other words, the first connection surface 3031 can be fixedly connected to the side plate 104. The second connection surface 3032 is fixedly connected to the flexible flat cable 301 via adhesive. In other words, the second connection surface 3032 can be fixedly connected to the flexible flat cable 301. In this embodiment, the first connection surface 3031 and the second connection surface 3032 are set at, for example, a right angle. The fastener 304 may be, for example, a rivet or the like.

[0060] Referring to Figures 1, 17 to 21, in one embodiment of the present invention, when attaching the connecting component 300, first, the second connectors 302 at both ends of each flexible flat cable can be connected to the corresponding first connector 203 and the battery management system 108. Next, multiple layers of flexible flat cables 301 are stacked and installed, 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 multiple layers of flexible flat cables 301 as a single unit. Finally, the adapter sheet 303 is attached, the second connecting surface 3032 of the adapter sheet 303 is fixed to the flexible flat cable 301 with adhesive, the first connecting surface 3031 of the adapter sheet 303 is stacked on the side plate, and the first connecting surface 3031 is fixed to the side plate 104 using a fastener 304 or the like.

[0061] As described above, the present invention provides a battery pack comprising a lower housing 101, a cell stack 102 installed inside the lower housing 101, flexible circuit boards 201 installed on both sides of each cell stack 102, connecting components 300 including a flexible flat cable 301, a plastic sheet 204 or thermocompression film 209 for fixing the flexible circuit boards 201, and a fixing plate 207 for fixing a temperature sampling terminal 205. The battery pack provided by the present invention does not require the separate installation of independent bracket structures on the flexible circuit boards 201 and the like, thus improving the volume utilization rate and energy density of the battery pack.

[0062] The above description is merely a description of more preferred embodiments of the present application and applicable technical principles. Those skilled in the art should understand that the scope of the present application is not limited to solutions formed by specific combinations of the above-described technical features, but also includes other solutions formed by any combination of the above-described technical features or their equivalents, without departing from the concept of the invention, such as solutions formed by substituting the above-described features with (but not limited to) similar functional technical features disclosed in the present application.

[0063] Aside from the technical features described in the specification, other technical features are known to those skilled in the art; therefore, in order to emphasize the innovative features of the present invention, these other technical features will not be described again here. [Industrial applicability]

[0064] The battery pack of the present invention can be applied in the technical field of power batteries. [Explanation of symbols]

[0065] 101 Lower enclosure 102 Cell Stack 1021 First Cell Stack 1022 Second Cell Stack 103 Case intermediate beam 104 Side panel 105 Foaming Adhesive 106 Top cover 107 Buckle 108 Battery Management System 200 Flexible Circuit Board Assemblies 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 First 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-seal film 2091 First Thermocompression Film 2092 Second Thermo-Seal Film 2093 First thermocompression surface 2094 Second thermocompression surface 2095 2nd protrusion 300 connecting parts 301 Flexible Flat Cable 302 Second connector 303 Adapter Sheet 3031 First connection surface 3032 Second connection surface 304 Fixtures

Claims

1. The case, including the lower enclosure, A cell stack comprising a plurality of pouch-type battery cells stacked sequentially in the thickness direction of the cell, wherein the stacking direction of the pouch-type battery cells is referred to as the stacking direction, and the cell stack includes two sides located on opposite sides in the stacking direction and two tab sides adjacent to the two opposing sides, and the cell stack is installed in the lower housing, A foam adhesive is filled and connected between the tab side of the cell stack and the lower housing, A side plate fixed to the side of the cell stack, A flexible circuit board assembly comprising a flexible circuit board and an insulating connection sheet, wherein the flexible circuit board is connected and fixed to the cell stack via the insulating connection sheet, Battery management system and A connecting component is connected to the battery management system and the flexible circuit board for communication purposes and is fixed to the side plate, A battery pack that includes this.

2. The battery pack according to claim 1, wherein the flexible circuit board includes a flexible circuit board body, and the flexible circuit board body is provided with a plurality of sampling sheets distributed along the stacking direction of the pouch-type battery cells, and the sampling sheets are welded and fixed to the tabs of the corresponding pouch-type battery cells.

3. The battery pack according to claim 2, wherein the insulating connection sheet includes a plastic sheet.

4. The battery pack according to claim 3, wherein the flexible circuit board body is located on the tab side of the cell stack, the plastic sheet includes a first fixed surface and a second fixed surface connected to each other, the second fixed surface is bonded to the flexible circuit board body, and the first fixed surface is bonded to the upper surface of the cell stack to fix the flexible circuit board body.

5. The battery pack according to claim 4, wherein a plurality of first openings are provided on the first fixed surface, the first openings are close to the connection portion between the first fixed surface and the second fixed surface, and correspond to the sampling sheet.

6. The battery pack according to claim 3, wherein the flexible circuit board body is bonded and fixed to the plastic sheet, and the plastic sheet is bonded and fixed to the cell stack.

7. The battery pack according to claim 2, wherein the flexible circuit board assembly further includes a first connector, the ends of the flexible circuit board body being bent in the same direction to form a fixing portion that hooks onto the side plate, the first connector being installed on the fixing portion and electrically connected to the battery management system via the connecting component.

8. The battery pack according to claim 2, further comprising a temperature sampling terminal and a fixing plate, wherein the temperature sampling terminal is connected to and fixed to the cell stack via the fixing plate.

9. The battery pack according to claim 8, wherein both ends of the fixing plate extend along the stacking direction of the pouch-type battery cells in the cell stack and are connected and fixed to the corresponding side plates.

10. The battery pack according to claim 8, wherein the flexible circuit board body is located on the tab side of the cell stack, the temperature sampling terminal is located on the upper surface side of the cell stack, the flexible circuit board further includes a plurality of stretched structures, and both ends of the stretched structures are connected to the flexible circuit board body and the temperature sampling terminal, respectively.

11. The battery pack according to claim 10, wherein a reinforcing plate is installed at one end of the stretched structure connected to the temperature sampling terminal, the reinforcing plate and the temperature sampling terminal are located on opposite sides of the stretched structure, the reinforcing plate faces the upper surface of the cell stack, the fixing plate is provided with a second opening corresponding to the temperature sampling terminal, and the fixing plate is pressed against the stretched structure and / or the reinforcing plate and bonded to the upper surface of the cell stack.

12. The battery pack according to claim 10 or 11, wherein both ends of the fixing plate are bent in the same direction to form a curved structure, and the curved structure is fixedly connected to the side plate.

13. The battery pack according to claim 1, wherein the connecting component includes a flexible flat cable and an adapter sheet, the flexible flat cable is installed on the side of the cell stack and connected and fixed to the side plate via the adapter sheet.

14. The battery pack according to claim 13, wherein the number of flexible flat cables is multiple, equal to the number of flexible circuit boards, and at least a portion of the multiple flexible flat cables are installed overlapping and connected and fixed to the side plate via the same adapter sheet.

15. The battery pack according to claim 14, wherein two adjacent layers of the flexible flat cable are fixed to each other with adhesive.

16. The battery pack according to claim 13, wherein the flexible flat cable is installed corresponding to the side surface of the cell stack, and the adapter sheet includes a first connection surface and a second connection surface, the first connection surface being fixedly connected to the side plate, and the second connection surface being fixedly connected to the flexible flat cable.

17. The battery pack according to claim 16, wherein the first connection surface is connected to the side plate by overlapping it and is fixed to the side plate via a fastener, and the second connection surface is fixed to the flexible flat cable with adhesive.

18. The battery pack according to claim 14, wherein one end of the flexible flat cable is connected to 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 along the same path.

19. The battery pack according to claim 14, wherein 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, the battery management system located on the other tab side of the first cell stack opposite to the second cell stack, one end of each of the flexible flat cables connected to the corresponding flexible circuit board, and the other ends of the multiple flexible flat cables extending across the sides of the first cell stack and / or the sides of the second cell stack and electrically connected to the same battery management system.

20. The battery pack according to claim 1, wherein the cell stack and the bottom plate of the lower housing are directly bonded and fixed with a thermally conductive structural adhesive.

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