Low-voltage battery system

Abstract

The utility model discloses a low-voltage battery system, and belongs to the technical field of batteries. The low-voltage battery system comprises a box body and battery cells, the box body comprises a box main body, the side face of the box main body is provided with battery cell containing grooves penetrating through the box main body in the first direction, the multiple battery cell containing grooves are independently arranged at intervals in the second direction, and the multiple battery cells are contained in the multiple battery cell containing grooves respectively; the side surface of the box main body is also provided with a communicating groove for communicating two adjacent battery cell accommodating grooves, the length of the communicating groove is smaller than that of the battery cell accommodating groove, and when the structural adhesive is injected, the adhesive can be injected from the communicating groove, so that the communicating groove is filled with the structural adhesive, the convenience of the adhesive injection operation can be improved, and the mounting stability of the battery cell is improved; the risk that the structural adhesive overflows and covers the end face of the battery cell can be reduced, and the stability of the low-voltage battery system is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a low-voltage battery system. BACKGROUND

[0002] The electric vehicle includes a high-voltage battery system and a low-voltage battery system, wherein the high-voltage battery system includes a power battery for driving the vehicle to run, and the power battery is controlled by a low-voltage controller to output high-voltage for driving the vehicle to run, and the low-voltage battery system can be used to power the low-voltage controller to ensure that the vehicle can normally start running.

[0003] In the related art, the low-voltage battery system for vehicle includes a box body, a plurality of battery cells and a BMS, wherein the box body has four battery cell accommodating grooves for accommodating the battery cells, and the four battery cells are respectively accommodated in the four battery cell accommodating grooves to realize 12V power supply of the low-voltage battery system. In order to improve the stability of the battery cells in the battery cell accommodating grooves, it is usually necessary to inject structural adhesive between the battery cells and the battery cell accommodating grooves to fix the battery cells in the battery cell accommodating grooves. However, when the battery cells are accommodated in the battery cell accommodating grooves, the gap between the battery cells and the inner wall of the battery cell accommodating grooves is small, and when the structural adhesive is injected, the structural adhesive is easy to overflow and cover the end face of the battery cell, thereby affecting the electrical connection between the battery cell and the BMS, and further affecting the stability of the low-voltage battery system.

[0004] This part provides background information related to the present application, which may not be prior art. Content of the utility model

[0005] The present application aims to solve or at least alleviate part or all of the above problems. To this end, the present application aims to provide a low-voltage battery system, which facilitates the injection of structural adhesive to improve the stability of the battery cell installation, while reducing the risk of structural adhesive overflow and covering the end face of the battery cell, and improving the stability of the low-voltage battery system.

[0006] In order to achieve the above-mentioned target, the present application adopts the following technical scheme:

[0007] The present application provides a low-voltage battery system, comprising:

[0008] The box body includes a box main body, and the side surface of the box main body has a plurality of battery cell accommodating grooves penetrating through the box main body along a first direction, and the plurality of battery cell accommodating grooves are spaced apart and independently arranged along a second direction, wherein the second direction is perpendicular to the first direction;

[0009] A plurality of battery cells are respectively accommodated in the plurality of battery cell accommodating grooves;

[0010] The side surface of the box body further has a communication groove communicating two adjacent cell accommodating grooves, the length of the communication groove is less than the length of the cell accommodating groove, and the gap between the cell and the cell accommodating groove and the communication groove are used for accommodating structural glue.

[0011] As an optional solution of the low-voltage battery system, in the first direction, the length of the communication groove is not greater than half of the length of the cell accommodating groove.

[0012] As an optional solution of the low-voltage battery system, the low-voltage battery system further comprises a BMS, the box body further comprises an upper cover, and the top surface of the box body has a closed area which cooperates with the upper cover to form a BMS accommodating cavity used for accommodating the BMS.

[0013] As an optional solution of the low-voltage battery system, the low-voltage battery system further comprises a plurality of interface elements, the top surface of the box body has an interface area, the interface elements have interface terminals which are exposed to the interface area, the part of the interface elements used for connecting with the cells extends into the cell accommodating grooves, and the part of the interface elements used for connecting with the BMS extends into the BMS accommodating cavity.

[0014] As an optional solution of the low-voltage battery system, all the interface elements are integrally formed with the box body.

[0015] As an optional solution of the low-voltage battery system, the low-voltage battery system further comprises a BMS input positive electrode, the BMS input positive electrode is integrally formed with the box body, the part of the BMS input positive electrode used for connecting with the cells extends into the cell accommodating grooves, and the part of the BMS input positive electrode used for connecting with the BMS extends into the BMS accommodating cavity.

[0016] As an optional solution of the low-voltage battery system, the low-voltage battery system further comprises a plurality of pressure sampling elements, the pressure sampling elements are integrally formed with the box body, the part of the pressure sampling elements used for connecting with the cells is exposed to the side surface of the box body, and the part of the pressure sampling elements used for connecting with the BMS extends into the BMS accommodating cavity.

[0017] As an optional solution of the low-voltage battery system, the bottom of the BMS has a temperature sensor, the closed area has a relief hole through which the temperature sensor penetrates, and the relief hole communicates with the cell accommodating groove.

[0018] As an optional solution of the low-voltage battery system, the interface elements comprise a communication interface, the communication interface has a communication interface terminal and a communication connection part integrally formed with the communication interface terminal, the communication interface terminal extends along the horizontal direction and is exposed to the interface area, and the communication connection part extends into the BMS accommodating cavity; and / or

[0019] As an optional solution of the low-voltage battery system, the interface elements comprise an output positive electrode interface, the output positive electrode interface has an output positive electrode terminal and a positive electrode connection part integrally formed with the output positive electrode terminal, the output positive electrode terminal extends along the height direction and is exposed to the interface area, and the positive electrode connection part extends into the battery cell accommodating groove; and / or

[0020] As an optional solution of the low-voltage battery system, the interface elements comprise an output negative electrode interface, the output negative electrode interface has an output negative electrode terminal and a negative electrode connection part integrally formed with the output negative electrode terminal, the output negative electrode terminal extends along the height direction and is exposed to the interface area, and the negative electrode connection part extends into the BMS accommodating cavity.

[0021] As an optional solution of the low-voltage battery system, the inner wall of the battery cell accommodating groove has a limiting protrusion at one end close to the interface element, and the limiting protrusion is used to abut against the end surface of the battery cell.

[0022] As an optional solution of the low-voltage battery system, the box body further comprises a front cover and a rear cover, and the front cover and the rear cover are respectively sealed and covered at both ends of the box body in the first direction.

[0023] As an optional solution of the low-voltage battery system, the upper cover and the box body are sealingly connected through welding; and / or

[0024] The front cover and the box body are sealingly connected through welding; and / or

[0025] The rear cover and the box body are sealingly connected through welding.

[0026] As an optional solution of the low-voltage battery system, the front cover has a gas permeable hole, and a gas permeable film is arranged at the gas permeable hole.

[0027] As an optional solution of the low-voltage battery system, the box body further comprises a protective cover, and the protective cover is detachably installed at the gas permeable hole.

[0028] As an optional solution of the low-voltage battery system, the closed area has a through hole communicating the battery cell accommodating groove and the BMS accommodating cavity.

[0029] The beneficial effects of the present application are:

[0030] The low-voltage battery system provided by the application comprises a box body and a cell, the box body comprises a box main body, the side of the box main body is provided with a cell accommodating groove penetrating through the box main body along a first direction, a plurality of cell accommodating grooves are arranged separately and spaced apart along a second direction, a plurality of cells are accommodated in the plurality of cell accommodating grooves respectively, and the side of the box main body is further provided with a communication groove communicating between two adjacent cell accommodating grooves, the length of the communication groove is less than the length of the cell accommodating groove, when structural glue is injected, the injection can be performed from the communication groove, the structural glue can be filled in the communication groove, the convenience of the injection operation can be improved, the installation stability of the cell can be improved, the risk that the structural glue overflows and covers the end surface of the cell can be reduced, and the stability of the low-voltage battery system is improved. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed to be used in the description of the embodiments of the application will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the contents of the embodiments of the application and the drawings.

[0032] Figure 1 A structural schematic diagram of a low-voltage battery system provided by an embodiment of the application is shown.

[0033] Figure 2 An exploded schematic diagram of a low-voltage battery system provided by an embodiment of the application is shown.

[0034] Figure 3 A structural schematic diagram of a cell and a BMS electrically connected provided by an embodiment of the application is shown.

[0035] Figure 4 A structural schematic diagram of a BMS provided by an embodiment of the application is shown. Figure 3 A structural schematic diagram of a BMS provided by an embodiment of the application is shown.

[0036] Figure 5 A structural schematic diagram of an interface element and a box main body provided by an embodiment of the application is shown.

[0037] Figure 6 A structural schematic diagram of a box main body provided by an embodiment of the application is shown.

[0038] Figure 7 A structural schematic diagram of a cell mounted on a box main body and filled with glue provided by an embodiment of the application is shown.

[0039] Reference signs:

[0040] 1, box; 11, box body; 111, battery cell accommodating groove; 1111, limiting protrusion; 112, interface area; 113, closed area; 1131, avoiding hole; 1132, through hole; 1133, positioning column; 114, groove; 115, communication groove; 12, upper cover; 13, front cover; 131, air hole; 14, rear cover; 16, protective cover;

[0041] 2, battery cell;

[0042] 3, BMS; 31, temperature sensor; 32, positioning hole;

[0043] 41, communication interface; 411, communication interface terminal; 412, communication connection part; 42, output positive electrode interface; 421, output positive electrode terminal; 422, positive electrode connection part; 43, output negative electrode interface; 431, output negative electrode terminal; 432, negative electrode connection part; 44, BMS input positive electrode; 441, BMS input battery cell connection part; 442, BMS input BMS connection part; 45, pressure sampling element; 451, pressure sampling battery cell connection part; 452, pressure sampling BMS connection part;

[0044] 5, battery cell series sheet;

[0045] 6, structural adhesive. DETAILED DESCRIPTION

[0046] Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the above-described accompanying drawings.

[0047] In this application, the terms "comprise", "contain", "have" or any other variant thereof are intended to cover non-exclusive inclusions, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or device. Without more limitations, the element defined by the statement "comprising a" does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0048] In this application, the term "and / or", is a description of the association relationship between the associated objects, which means that there can be three kinds of relationships. For example, A and / or B, can represent: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this application generally represents that the front and rear associated objects are in a "and / or" relationship.

[0049] In this application, the terms "connect", "couple", "coupled", "mount", "mounting" can be direct connection, coupling or mounting, or indirect connection, coupling or mounting. Among them, for example, direct connection refers to the connection of two parts or components without the need for an intermediate part, and indirect connection refers to the connection of two parts or components with at least one intermediate part. In addition, "connection" and "coupling" are not limited to physical or mechanical connection or coupling, and can include electrical connection or coupling.

[0050] In this application, those of ordinary skill in the art will understand that the relative terms used in connection with the number or condition (for example, "about", "approximately", "substantially" and the like) include the value indicated by the context. For example, the relative terms at least include the degree of error related to the measurement of a specific value, the tolerance caused by manufacturing, assembly, use, etc. related to a specific value. Such terms should also be considered to disclose the range defined by the absolute values of the two endpoints. The relative term can refer to the indicated value plus or minus a certain percentage (for example, 1%, 5%, 10% or more). The numerical value without the relative term should also be disclosed as a specific value with a tolerance. In addition, "substantially" when expressing the relative angular positional relationship (for example, substantially parallel, substantially perpendicular), it can refer to plus or minus a certain degree (for example, 1 degree, 5 degrees, 10 degrees or more) based on the indicated angle.

[0051] In this application, those of ordinary skill in the art will understand that the functions performed by the components can be performed by one component, multiple components, one part, or multiple parts. Similarly, the functions performed by the parts can also be performed by one part, one component, or multiple parts in combination.

[0052] In this application, the terms "up", "down", "left", "right", "front", "back" and the like are described in the orientation and positional relationship shown in the drawings, and should not be understood as limiting the embodiments of the application. In addition, it should also be understood in the context that when referring to one element connected to another element "up" or "down", it can not only be directly connected to another element "up" or "down", but also indirectly connected to another element "up" or "down" through an intermediate element. It should also be understood that the terms "up", "down", "left", "right", "front", "back" and the like not only represent the positive direction, but also can be understood as the side direction. For example, the lower side can include the lower side, the lower left side, the lower right side, the lower front side and the lower back side, etc.

[0053] The application provides a low-voltage battery system which can be used in an electric vehicle, and is used to provide low-voltage electricity for low-voltage controller and other low-voltage electrical elements of the electric vehicle, so as to ensure that the electric vehicle can start running smoothly.

[0054] Figure 1 A structural schematic diagram of a low-voltage battery system provided by an embodiment of the application is shown. Figure 2 A structural schematic diagram of a low-voltage battery system provided by an embodiment of the application is shown. As shown in the figure, the low-voltage battery system comprises a box body 1, a battery cell 2 and a BMS 3, the battery cell 2 and the BMS 3 are accommodated in the box body 1, the battery cell 2 is used for power supply, and the BMS 3 is used for real-time monitoring of the battery cell 2 to avoid thermal runaway caused by overcharging of the battery cell 2 or other reasons, thereby improving the stability and safety of the low-voltage battery system. Figures 1 to 2

[0055] The box body 1 comprises a box main body 11 and an upper cover 12, the side surface of the box main body 11 is provided with a battery cell accommodating groove 111 for accommodating the battery cell 2, the top surface of the box main body 11 is provided with an interface area 112 and a closed area 113, and the closed area 113 cooperates with the upper cover 12 to form a BMS accommodating cavity for accommodating the BMS 3. This design can realize separate cavity installation of the battery cell 2 and the BMS 3, fully utilize the structural space of the box main body 11, reduce the processing difficulty of the box body 1, reduce the influence of pressure relief of the battery cell 2 on the BMS 3 and the electrical connection part, and improve the stability and safety of the battery as a whole.

[0056] In this embodiment, the low-voltage battery system is mainly a 12V low-voltage battery system, the number of the battery cell accommodating grooves 111 is four, the four battery cell accommodating grooves 111 are arranged at intervals, and each battery cell accommodating groove 111 accommodates one battery cell 2. The low-voltage battery system further comprises a battery cell series connecting tab 5, and the four battery cells 2 are connected in series through three battery cell series connecting tabs 5. In other embodiments, the number of the battery cell accommodating grooves 111 can also be designed according to the number of the battery cells 2 required, which is not limited herein.

[0057] For the convenience of description, the extension direction of the battery cell accommodating groove 111 is defined as the "first direction", the arrangement direction of the battery cell accommodating grooves 111 is defined as the "second direction", and the height direction of the box body 1 is defined as the "height direction".

[0058] In this embodiment, the battery cell 2 is a cylindrical battery cell, the battery cell accommodating groove 111 extends along the first direction and penetrates through the box main body 11, so as to facilitate installation of the battery cell 2 in the battery cell accommodating groove 111 and subsequent glue filling operation.

[0059] The box body 1 further comprises a front cover 13 and a rear cover 14, and the front cover 13 and the rear cover 14 are respectively sealed and arranged at both ends of the box main body 11 in the first direction. Among them, the front cover 13 is located at the positive electrode end of the battery cell 2, and the rear cover 14 is located at the negative electrode end of the battery cell 2. Through the arrangement of the front cover 13 and the rear cover 14, the battery cell 2 can be packaged to improve the safety of the battery cell 2.

[0060] ​The front cover 13 is provided with a ventilation hole 131, and a ventilation film is arranged at the ventilation hole 131, which is used to balance the air pressure in the box body 1, so as to facilitate subsequent air tightness test. In addition, the ventilation film is only used for gas exchange, which can prevent water or other sundries from entering the box body 1, not only facilitating the gas exchange between the battery cell containing groove 111 and the outside world to effectively avoid the explosion of the box body 1 due to excessive pressure, but also preventing the water or sundries from the outside world from entering the box body 1 to cause the short circuit of the electronic elements in the box body 1.

[0061] In order to protect the ventilation film, the box body 1 further comprises a protection cover 16, which is arranged outside the ventilation hole 131 to avoid that the sharp objects from the outside world enter the ventilation hole 131 to pierce the ventilation film. It can be understood that the installation between the protection cover 16 and the ventilation hole 131 is non-sealed installation, so as to ensure that the gas can exchange through the gap between them.

[0062] In the embodiment, the front cover 13 has a certain thickness, that is, the ventilation hole 131 has a certain length, the ventilation film is installed at one end of the ventilation hole 131 close to the battery cell 2, and the protection cover 16 is installed at one end of the ventilation hole 131 away from the battery cell 2.

[0063] The box body 11, the upper cover 12, the front cover 13 and the rear cover 14 are plastic parts. The plastic parts have the advantages of convenient processing, low cost and good insulation, which can provide better protection for the battery cell 2 and the electronic elements in the box body 1. In order to improve the sealing performance of the box body 1 as a whole, the upper cover 12 is sealed and connected to the box body 11 by welding to realize the sealing protection of IP67 level for the BMS 3. Similarly, the front cover 13 is sealed and connected to the box body 11 by welding, and the rear cover 14 is sealed and connected to the box body 11 by welding to realize the sealing protection of IP67 level for the battery cell 2.

[0064] Figure 3 A structure diagram of the electrical connection between the battery cell 2 and the BMS 3 provided by the embodiment of the application is shown. Figure 4 A structure diagram of the electrical connection between the battery cell 2 and the BMS 3 provided by the embodiment of the application is shown. Figure 3 A structure diagram of the BMS 3 is hidden. As shown in Figures 3 to 4 The low-voltage battery system provided by the application further comprises a plurality of interface elements, part of which are used to connect the battery cell 2 and the BMS 3, part of which are used to connect the battery cell 2 and an external low-voltage power consumption unit (such as a low-voltage controller), and part of which are used to connect the BMS 3 and the external low-voltage power consumption unit (such as a low-voltage controller).

[0065] In the related art, the interface elements of the low-voltage battery system all need to use a plurality of conductive elements (such as copper bars or wires) to connect the battery cell 2 and / or the BMS 3, and the number of conductive elements is large, and the layout of the conductive elements and the assembly thereof and the box body 1 become the main technical difficulties in the processing of the low-voltage battery system.

[0066] Figure 5 The structural schematic diagram of the interface element and the box body 11 provided by the embodiment of the application is shown. As shown in Figure 5 In combination Figure 3 , Figure 4 In order to solve the above problems, the interface element and the box body 11 are integrally formed, the interface element has interface terminals, the interface terminals are exposed to the interface area 112, the part of the interface element for connecting with the battery cell 2 extends into the battery cell accommodating groove 111, and the part of the interface element for connecting with the BMS 3 extends into the BMS accommodating cavity. In this way, the number of parts of the low-voltage battery system can be reduced, and the assembly time of the interface element and the related conductive element can be saved, and the assembly precision and efficiency are improved.

[0067] The communication interface 41 is included in the plurality of interface elements, the communication interface 41 has a communication interface terminal 411 and a communication connecting part 412 integrally formed with the communication interface terminal 411, the communication interface terminal 411 extends along the horizontal direction (specifically, along the first direction) and is exposed to the interface area 112, and the communication connecting part 412 extends into the BMS accommodating cavity. It can be understood that the communication interface terminal 411 is arranged along the first direction, which can save the space of the low-voltage battery system in the height direction, and facilitates the assembly of the low-voltage battery system into the electric vehicle.

[0068] The output positive interface 42 and the output negative interface 43 are included in the plurality of interface elements, the output positive interface 42 has an output positive terminal 421 and a positive connecting part 422 integrally formed with the output positive terminal 421, the output positive terminal 421 extends along the height direction and is exposed to the interface area 112, and the positive connecting part 422 extends into the battery cell accommodating groove 111. The output negative interface 43 has an output negative terminal 431 and a negative connecting part 432 integrally formed with the output negative terminal 431, the output negative terminal 431 extends along the height direction and is exposed to the interface area 112, and the negative connecting part 432 extends into the BMS accommodating cavity. In addition, the output negative interface 43 is electrically connected with the negative electrode of the battery cell 2 through the BMS 3, and the output negative interface 43 cooperates with the output positive interface 42 to form the electrical output interface of the low-voltage battery system. For example, the output positive terminal 421 and the output negative terminal 431 can be selected as output studs, and the positive connecting part 422 and the negative connecting part 432 can be selected as copper bars.

[0069] Further, the low-voltage battery system further comprises a BMS input positive pole 44 which is integrally formed with the box body 11, and the part of the BMS input positive pole 44 which is used for connecting with the battery cell 2 (i.e. the BMS input cell connecting part 441) extends into the battery cell accommodating groove 111, and the part of the BMS input positive pole 44 which is used for connecting with the BMS 3 (i.e. the BMS input BMS connecting part 442) extends into the BMS accommodating cavity. It should be noted that the BMS input positive pole 44 and the output negative pole interface 43 are both connected with the BMS 3, and then connected through a plurality of mos tubes on the BMS 3.

[0070] In order to facilitate the BMS 3 to collect the voltage information of the battery cell 2, the low-voltage battery system further comprises a plurality of voltage sampling elements 45 which are integrally formed with the box body 11, and the part of the voltage sampling element 45 which is used for connecting with the battery cell 2 (i.e. the voltage sampling cell connecting part 451) is exposed on the side surface of the box body 11, and the part of the voltage sampling element 45 which is used for connecting with the BMS 3 (i.e. the voltage sampling BMS connecting part 452) extends into the BMS accommodating cavity. This design can save the assembly of the voltage sampling element 45 and improve the assembly efficiency.

[0071] It should be noted that the molding scheme of the integrally forming the communication interface 41, the output positive pole interface 42, the output negative pole interface 43, the BMS input positive pole 44 and the voltage sampling element 45 with the box body 11 can be selected as embedded injection molding, that is, the communication interface 41, the output positive pole interface 42, the output negative pole interface 43, the BMS input positive pole 44 and the voltage sampling element 45 are arranged in the corresponding positions of the mold in advance, and then the box body 11 is injection molded.

[0072] In order to realize the collection of the temperature of the battery cell 2, the bottom of the BMS 3 is provided with a temperature sensor 31, the closed area 113 is provided with a relief hole 1131 through which the temperature sensor 31 penetrates, and the relief hole 1131 is in communication with the battery cell accommodating groove 111. The temperature sensor 31 is accommodated in the relief hole 1131 and extends to a position close to the battery cell 2, so as to better collect the temperature change of the battery cell 2, so as to facilitate the BMS 3 to adopt a suitable control strategy and improve the stability and safety of the battery.

[0073] In the embodiment, the temperature sensor 31 is directly integrated on the BMS 3, which can save the cost of parts wire harness, connector and the like, and can reduce the space requirement.

[0074] Continuing to refer to Figure 5 and Figure 3As shown, the closed area 113 of the box body 11 has positioning posts 1133, and the BMS 3 has positioning holes 32 matched with the positioning posts 1133, so as to facilitate positioning installation of the BMS 3. In the embodiment, the number of the positioning posts 1133 is two, and the two positioning posts 1133 are arranged at intervals along the second direction, and the positioning holes 32 on the BMS 3 are arranged one by one with the positioning posts 1133. In other embodiments, the number and layout mode of the positioning posts 1133 and the positioning holes 32 can also adopt other forms, which can be designed according to actual needs, and are not limited herein.

[0075] Further, the closed area 113 of the box body 11 has a through hole 1132 connecting the cell accommodating groove 111 and the BMS accommodating cavity, and the through hole 1132 is used to ensure the gas flowability of the whole box body 1 during the airtightness test.

[0076] Continuing to refer to Figure 5 and Figure 2 As shown, the side of the box body 11 has a groove 114 accommodating the cell series tab 5, so that after installation of the cell series tab 5, the side of the box body 11 is relatively flat as a whole, which not only facilitates installation of the front cover 13, but also can avoid excessive extrusion of the cell series tab 5 by the front cover 13.

[0077] In order to position the cell 2, the inner wall of the cell accommodating groove 111 has a limiting convex 1111 at one end close to the interface element, and the limiting convex 1111 is used to abut against the end face of the cell 2. In the embodiment, the number of the limiting convex 1111 is four, and the four limiting convexes 1111 are uniformly arranged at intervals around the cell accommodating groove 111, and when the cell 2 is installed, the cell 2 abuts against the limiting convex 1111, which indicates that the cell 2 is installed in place.

[0078] Figure 6 A structural schematic diagram of the box body 11 provided by the embodiment of the application is shown. Figure 7 A structural schematic diagram of the cell 2 installed in the box body 11 and filled with glue is shown. As shown in Figures 6 to 7As shown, the plurality of battery cell accommodating grooves 111 are spaced apart and independently arranged along the second direction, the box body 11 has a communication groove 115 on the side away from the interface element, the communication groove 115 communicates two adjacent battery cell accommodating grooves 111, and the length of the communication groove 115 is less than the length of the battery cell accommodating groove 111. The communication groove 115 is used to accommodate the structural adhesive 6. When injecting the structural adhesive, the structural adhesive can be injected from the communication groove 115, so that the communication groove 115 is filled with the structural adhesive. This not only improves the convenience of the injection operation, thereby improving the installation stability of the battery cell 2, but also reduces the risk of structural adhesive overflowing and covering the end surface of the battery cell 2, thereby improving the stability of the low-voltage battery system. In addition, the communication groove 115 not only accommodates the structural adhesive 6, but also limits the structural adhesive 6. The structural adhesive 6 can further fix the battery cell 2 in the box body 11, reduce the shaking of the battery cell 2, and improve the safety of the battery cell 2.

[0079] It should be noted that when injecting the structural adhesive 6, the viscosity of the structural adhesive 6 can be adjusted so that the structural adhesive 6 only fills the communication grooves between the two adjacent battery cells 2. The structural adhesive 6 in the communication groove 115 is used to fix the two adjacent battery cells 2, without the need to fill the structural adhesive 6 between the battery cell 2 and the battery cell accommodating groove 111. This further avoids the structural adhesive 6 flowing to the end surface of the battery cell 2, while reducing the amount of structural adhesive 6 used and reducing costs.

[0080] In an embodiment, the length of the communication groove 115 in the first direction is not greater than half the length of the battery cell accommodating groove 111 in the first direction. In this way, the injected structural adhesive 6 can stably fix the battery cell 2 in the battery cell accommodating groove 111, and ensure the connection stability between the two adjacent battery cells 2. In addition, the amount of structural adhesive used can be reduced, thereby reducing costs.

[0081] For the above low-voltage battery system, the application also provides an assembly process of the low-voltage battery system. The assembly method comprises the following steps: 1) integrally forming the interface element, the BMS input positive electrode 44, the pressure sampling element 45, etc. in the box body 11; 2) installing the BMS 3 and completing the BMS 3 wiring operation; 3) installing the upper cover 12; 4) installing the battery cell 2; 5) pouring the structural adhesive 6; 6) installing the rear cover 14; 7) battery cell 2 wiring; 8) installing the front cover 13; 9) air tightness test. The assembly process of the low-voltage battery system is simple, the space utilization of the box body 11 is high, and the air tightness test can be performed.

[0082] The basic principles, main features and advantages of the application are shown and described above. Those skilled in the art should understand that the above embodiments do not limit the application in any form, and any technical solutions obtained by equivalent replacement or equivalent transformation fall within the scope of the application.

Claims

1. A low voltage battery system, characterized by The low-voltage battery system comprises: a box body (1) comprising a box main body (11), a side surface of the box main body (11) having a plurality of battery cell accommodating grooves (111) penetrating through the box main body (11) along a first direction, the plurality of battery cell accommodating grooves (111) being spaced apart and independently arranged along a second direction perpendicular to the first direction; a plurality of battery cells (2) respectively accommodated in the plurality of battery cell accommodating grooves (111); the side surface of the box main body (11) further having a plurality of communication grooves (115) communicating adjacent two battery cell accommodating grooves (111), the plurality of communication grooves (115) having a length smaller than that of the battery cell accommodating grooves (111), and the plurality of communication grooves (115) being used for accommodating structural glue (6).

2. The low voltage battery system of claim 1, wherein, The low-voltage battery system further comprises a BMS (3), and the box body (1) further comprises an upper cover (12), a top surface of the box main body (11) having a closed area (113) cooperating with the upper cover (12) to form a BMS accommodating cavity used for accommodating the BMS (3).

3. The low voltage battery system of claim 2, wherein, The low-voltage battery system further comprises a plurality of interface elements, the top surface of the box main body (11) having an interface area (112), the plurality of interface elements having interface terminals exposed to the interface area (112), a part of the plurality of interface elements used for connecting the battery cells (2) extending into the battery cell accommodating grooves (111), and a part of the plurality of interface elements used for connecting the BMS (3) extending into the BMS accommodating cavity.

4. The low voltage battery system of claim 3, wherein, All the plurality of interface elements are integrally formed with the box main body (11).

5. The low voltage battery system of claim 3, wherein, The low-voltage battery system further comprises a BMS input positive electrode (44), the BMS input positive electrode (44) being integrally formed with the box main body (11), a part of the BMS input positive electrode (44) used for connecting the battery cells (2) extending into the battery cell accommodating grooves (111), and a part of the BMS input positive electrode (44) used for connecting the BMS (3) extending into the BMS accommodating cavity.

6. The low voltage battery system of claim 3, wherein, The low-voltage battery system further comprises a plurality of pressure sampling elements (45), the plurality of pressure sampling elements (45) being integrally formed with the box main body (11), a part of the plurality of pressure sampling elements (45) used for connecting the battery cells (2) being exposed to the side surface of the box main body (11), and a part of the plurality of pressure sampling elements (45) used for connecting the BMS (3) extending into the BMS accommodating cavity.

7. The low voltage battery system of claim 3, wherein, A bottom of the BMS (3) has a temperature sensor (31), the closed area (113) has an avoiding hole (1131) for the temperature sensor (31) to pass through, and the avoiding hole (1131) is communicated with the battery cell accommodating grooves (111).

8. The low voltage battery system of claim 3, wherein, The plurality of interface elements comprise a communication interface (41), the communication interface (41) having a communication interface terminal (411) extending along a horizontal direction and exposed to the interface area (112), and a communication connecting portion (412) integrally formed with the communication interface terminal (411) and extending into the BMS accommodating cavity; and / or The interface elements include an output positive electrode interface (42), the output positive electrode interface (42) has an output positive electrode terminal (421) and a positive electrode connecting part (422) integrated with the output positive electrode terminal (421), the output positive electrode terminal (421) extends along the height direction and is exposed to the interface area (112), and the positive electrode connecting part (422) extends into the battery cell accommodating groove (111); and / or The interface elements include an output negative electrode interface (43), the output negative electrode interface (43) has an output negative electrode terminal (431) and a negative electrode connecting part (432) integrated with the output negative electrode terminal (431), the output negative electrode terminal (431) extends along the height direction and is exposed to the interface area (112), and the negative electrode connecting part (432) extends into the BMS accommodating cavity.

9. The low voltage battery system of claim 3, wherein, The inner wall of the battery cell accommodating groove (111) has a limiting convex (1111) at one end close to the interface element, the limiting convex (1111) is used to abut against the end face of the battery cell (2).

10. The low voltage battery system of claim 3, wherein, The box body (1) further includes a front cover (13) and a rear cover (14), the front cover (13) and the rear cover (14) are respectively sealed and covered on both ends of the box main body (11) in the first direction.

11. The low voltage battery system of claim 10, wherein, The upper cover (12) and the box main body (11) are sealed and connected by welding; and / or The front cover (13) and the box main body (11) are sealed and connected by welding; and / or The rear cover (14) and the box main body (11) are sealed and connected by welding.

12. The low voltage battery system of claim 10, wherein, The front cover (13) has a gas permeable hole (131), and a gas permeable film is arranged at the gas permeable hole (131).

13. The low voltage battery system of claim 12, wherein, The box body (1) further includes a protective cover (16), and the protective cover (16) is detachably installed at the gas permeable hole (131).

14. The low voltage battery system of claim 3, wherein, The closed area (113) has a through hole (1132) communicating the battery cell accommodating groove (111) and the BMS accommodating cavity.

Images