Battery module, battery pack, power consumption device, and method of manufacturing battery module

Abstract

The present application provides a battery module including at least two battery cell rows including a first battery cell row and a second battery cell row stacked adjacent to each other along a width direction of the battery cells, the first battery cell row and the second battery cell row collectively including a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and a center line in a length direction of at least one battery cell in the first battery cell row and a center line in a length direction of at least one battery cell in the second battery cell row are not collinear along the width direction of the battery cells. The present application further provides a battery pack, a power consumption device, and a method for manufacturing the battery module.

Description

[Technical Field]

[0001] The present application relates to the field of batteries, and more particularly to battery modules, battery packs, power consuming devices, and methods for manufacturing battery modules. [Background technology]

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles have become an important component in this field due to their energy-saving and environmentally friendly advantages. For electric vehicles, battery technology is a key factor in their development.

[0003] There is a constant need for improvements in battery technology, such as increasing the energy density of the battery pack, strengthening the structural strength of the battery pack, increasing the degree of temperature uniformity of the battery pack, and improving the heat dissipation of the battery pack. Summary of the Invention

[0004] In view of the above problems, the present application provides a battery module, a battery pack, and a power consumption device that can achieve at least one of improving the energy density of the battery pack, strengthening the structural strength of the battery pack, increasing the degree of temperature uniformity of the battery pack, and improving the heat dissipation performance of the battery pack.

[0005] According to a first aspect, the present application provides a battery module including at least two battery cell rows, including a first battery cell row and a second battery cell row, stacked along the width direction of the battery cells and adjacent to each other, the first battery cell row and the second battery cell row collectively including a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and a longitudinal center line of at least one battery cell in the first battery cell row and a longitudinal center line of at least one battery cell in the second battery cell row not being on the same line along the width direction of the battery cells.

[0006] The staggered structure of battery cells of different lengths in the present application can enhance the structural strength of the battery pack, and the centers of the surfaces with the largest areas of battery cells in adjacent rows are offset from each other along the width direction of the battery cells, thereby reducing the degree of expansion along the width direction of the battery cells after adding up the expansion of the centers of the surfaces with the largest areas of multiple battery cell rows, and effectively controlling the degree of expansion of the entire battery module. This reduces the possibility of the side structures of the battery pack located in the width direction of the battery cells in the battery pack suffering from severe extrusion deformation and even breakage due to the expansion of the entire battery module after the battery module is installed in the battery pack, thereby lowering the requirements for the strength of the side structures of the battery pack and further reducing the weight of the entire battery pack.

[0007] In some embodiments, the first and second battery cell rows have the same overall length, and the longitudinal edges of the first and second battery cell rows are flush. By having adjacent battery cell rows have the same length and flush longitudinal edges, the battery module can be formed into a regular shape such as a rectangular prism, maximizing space utilization and improving energy density.

[0008] In some embodiments, the longitudinal centerline of each battery cell in the first battery cell row is not collinear with the longitudinal centerline of each battery cell in the second battery cell row along the width direction of the battery cells. The effect of the staggered structure can be further improved by arranging the battery cells in adjacent battery cell rows so that the centerlines are not collinear along the width direction of the battery cells.

[0009] In some embodiments, the plurality of battery cells includes first and second battery cells, the first and second battery cells having different lengths, where the long battery cells can provide high rigidity and the short battery cells can provide good heat dissipation, and by combining the battery cells of different lengths, a good balance and optimization between the overall rigidity and heat dissipation of the battery module can be achieved.

[0010] In some embodiments, the first battery cell row is configured by arranging first battery cells along the length direction, and the second battery cell row is configured by arranging second battery cells along the length direction. This provides options for selecting and arranging battery cells within a battery module. Appropriate selection can be made depending on the size and energy density requirements of the battery module.

[0011] In some embodiments, the first battery cell row is configured by arranging first battery cells along the length direction, and the second battery cell row is configured by arranging first battery cells and second battery cells along the length direction. This provides different options for selecting and arranging battery cells within a battery module. Appropriate selection can be made depending on the size and energy density requirements of the battery module.

[0012] In some embodiments, the first battery cell row is configured by arranging the first battery cells and the second battery cells in a first order along the length direction, and the second battery cell row is configured by arranging the first battery cells and the second battery cells in a second order along the length direction, where the first order and the second order are different. This provides different options for selecting and arranging the battery cells within the battery module. Appropriate selection can be made depending on the size requirements and energy density requirements of the battery module.

[0013] In some embodiments, the first battery cell row includes m layers of first battery cells arranged along the width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, where the m layers of first battery cells and the n layers of second battery cells are arranged along the length direction of the battery cells, m and n are different, and the m layers of first battery cells and the n layers of second battery cells have the same width. This allows batteries of different widths to be arranged in the same row, providing different options for selecting and arranging battery cells within a battery module. Appropriate selection can be made depending on the size and energy density requirements of the battery module.

[0014] In some embodiments, the second battery cell row includes m layers of first battery cells arranged along the width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, where the m layers of first battery cells and the n layers of second battery cells are arranged along the length direction of the battery cells, where m and n are different, and the m layers of first battery cells and the n layers of second battery cells have the same width. This allows batteries of different widths to be arranged in the same row, providing different options for selecting and arranging battery cells within a battery module. Appropriate selection can be made depending on the size and energy density requirements of the battery module.

[0015] In some embodiments, the plurality of battery cells further includes a third battery cell having a length different from that of the first battery cell and the second battery cell, the first battery cell row being configured by arranging the third battery cells along the length direction, and the second battery cell row including m layers of first battery cells arranged along the width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, the m layers of first battery cells and the n layers of second battery cells arranged along the length direction of the battery cells, m and n being different, and the m layers of first battery cells and the n layers of second battery cells having the same width. This provides another option for selecting and arranging battery cells within a battery module. An appropriate selection can be made depending on the size and energy density requirements of the battery module.

[0016] In some embodiments, the battery module further includes a third battery cell row adjacent to the second battery cell row in the width direction, and the arrangement of the battery cells in the third battery cell row is the same as the arrangement of the battery cells in the second battery cell row or the first battery cell row. This provides another option for selecting and arranging the battery cells in the battery module. The appropriate selection can be made according to the size and energy density requirements of the battery module.

[0017] In some embodiments, the battery module includes a plurality of first battery cell rows and a plurality of second battery cell rows arranged alternately along the width direction of the battery cells, and arranging the plurality of battery cell rows can further enhance the effect of the staggered structure and improve the energy of the battery pack.

[0018] In some embodiments, the battery module includes a plurality of first battery cell rows, a second battery cell row, and a third battery cell row arranged alternately along the width direction of the battery cells, and arranging the plurality of battery cell rows can further enhance the effect of the staggered structure and improve the energy of the battery pack.

[0019] In some embodiments, the length of the first battery cell is longer than the length of the second battery cell, and the centerline of the first battery cell in the first battery cell row in the width direction of the battery cells is substantially opposite to one sidewall of one second battery cell in the second battery cell row. Since the battery cells expand most severely along the centerline and less severely along the sidewalls, arranging the most and least expanded portions to face each other can further mitigate the cumulative expansion of battery cells along the width direction of adjacent rows of battery cells in the battery pack.

[0020] In some embodiments, the positive electrode active material of the first battery cell is different from the positive electrode active material of the second battery cell, which provides various options for battery cells in a battery pack, such as selecting an appropriate battery cell according to energy density requirements.

[0021] In some embodiments, the battery module includes two end plates arranged along the width direction, each end plate having a first surface close to the battery cells and a second surface farther from the battery cells, and the second surface has a middle portion and two inclined portions arranged along the vertical direction, the inclined portions being arranged on either side of the middle portion and inclined from the middle portion toward the first surface. The end plates are arranged such that the middle portions are thicker and the inclined portions are thinner than the middle portions, so that the middle portions of the end plates can withstand a greater expansion force at the center of the surface where the battery cells have the largest area, and the inclined portions on both sides are combined with a binding belt to help bind the rows of battery cells together.

[0022] In some embodiments, the end plate further includes two stoppers, each of which is located on a side of the inclined portion away from the middle portion, to prevent the binding belt from falling off the end plate.

[0023] In some embodiments, the battery module further includes a strap attached to the outer periphery, with one side of the strap connected to the upper inclined portion of one end plate and the other side connected to the lower inclined portion of the other end plate. The strap and the end plate are combined to bind the rows of battery cells in a manner that reduces the overall mass, and the strap is attached at an angle, so that the binding force is distributed throughout the thickness of the battery module, making the binding force more uniform and firm.

[0024] In some embodiments, there are two tie belts, and the two tie belts are crossed to ensure that the expansion forces on the top and bottom of the battery module are equalized, thereby avoiding the possibility of localized imbalance in the forces.

[0025] In some embodiments, the battery module includes a buffer material disposed between two adjacent rows of battery cells, which can effectively reduce the accumulation of battery cell expansion along the width direction of the battery cells in the battery pack, thereby preventing large tension from being generated in the packaging structure of the battery pack (such as the end plates of the battery module or the battery pack housing).

[0026] In some embodiments, the battery module includes a buffer material, the buffer material including an outer frame and one or more support ribs, the one or more support ribs are disposed inside the outer frame, and a hollow structure is formed between the support ribs and the outer frame, the hollow structure facing the surface with the largest area of ​​one of the battery cells in the first battery cell row or the second battery cell row, The support ribs are disposed to enhance the structural rigidity of the buffer material, and the hollow structure can also provide a buffer space for the expansion of the surface with the largest area of ​​the battery module.

[0027] In some embodiments, the support rib abuts against the longitudinal edge of at least one battery cell in two adjacent rows of battery cells. By arranging the support rib to abut against the longitudinal edge of the battery cell, it is possible to prevent the center of the largest surface from abutting against the edge of a battery cell in an adjacent row when the battery cell expands, thereby preventing the largest surface from being damaged and further improving the safety of the battery pack.

[0028] According to a second aspect, the present application further provides a battery pack including a frame and at least one battery module row as described above, wherein the at least one battery module row is housed within the frame, and each battery module row includes a plurality of battery modules arranged along the width direction of the battery cells.

[0029] In some embodiments, the battery pack includes at least two rows of battery modules, and a side member is provided between two adjacent rows of battery modules.

[0030] The advantages of the battery pack are the same as those of the battery module, and therefore will not be described here.

[0031] In some embodiments, the battery pack further includes a cooling structure, and the cooling structure includes a cooling channel extending in a detour along the width direction of the battery cells to allow a cooling fluid to flow. By providing the cooling channel extending in a detour along the width direction of the battery cells, a contact area with the battery cells can be increased, thereby further improving the cooling effect.

[0032] In some embodiments, the cross-sectional area of ​​the cooling channel in the middle of the battery module along the width direction of the battery cell is larger than the cross-sectional area of ​​the cooling channel in other parts of the battery module. By configuring the cross-sectional area of ​​the cooling channel to vary, the cooling effect in the middle of the battery pack can be improved and the temperature can be more uniform throughout the battery pack.

[0033] According to a third aspect, the present application further provides a power consuming device including the above battery pack used to supply electrical energy.

[0034] The advantages of the power consumption device are similar to those of the battery module, and therefore will not be described here.

[0035] According to a fourth aspect, the present application provides: providing a plurality of battery cells, some of the battery cells having a different length compared to the remaining battery cells; the plurality of battery cells are arranged in at least two battery cell rows along a width direction of the battery cells, the at least two battery cell rows including a first battery cell row and a second battery cell row adjacent to each other; and arranging the battery cells so that a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells.

[0036] The advantages of the manufacturing method for the battery module are the same as those of the battery module described above, and therefore a description thereof will be omitted here.

[0037] The above description is only a summary of the technical solution of the present application. In order to more clearly understand the technical solution of the present application, the following provides specific embodiments of the present application, which can be implemented according to the content of the specification, and to more clearly understand the above and other objectives, features and advantages of the present application. [Brief explanation of the drawings]

[0038] Various other advantages and benefits will be apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating the preferred embodiments and should not be construed as limiting the present application. In the various drawings, the same elements are designated by the same reference numerals.

[0039] [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Figure 2] 1 is a schematic exploded view of a typical battery pack used in a vehicle. [Figure 3] 1 is a schematic plan view of a battery pack according to a first embodiment of the present invention; [Figure 4] FIG. 10 is a schematic plan view of a battery pack according to a second embodiment of the present invention. [Figure 5] FIG. 10 is a schematic plan view of the structure of a battery pack according to a third embodiment of the present invention. [Figure 6] FIG. 10 is a schematic plan view of the structure of a fourth embodiment of the battery pack of the present invention. [Figure 7] FIG. 10 is a schematic plan view of the structure of a battery pack according to a fifth embodiment of the present invention. [Figure 8] FIG. 10 is a schematic plan view of the structure of a battery pack according to a sixth embodiment of the present invention. [Figure 9] FIG. 10 is a schematic plan view of the structure of a battery pack according to a seventh embodiment of the present invention. [Figure 10] FIG. 13 is a schematic plan view of the structure of an eighth embodiment of a battery pack according to the present invention. [Figure 11] FIG. 13 is a schematic plan view of the structure of a battery pack according to a ninth embodiment of the present invention. [Figure 12] FIG. 19 is a schematic plan view of the structure of a battery pack according to a tenth embodiment of the present invention. [Figure 13] FIG. 2 is a structural schematic diagram of an end plate according to the present application. [Figure 14] 1 is a schematic diagram of a side structure of a battery pack according to the present application. [Figure 15] FIG. 2 is a schematic exploded view of the battery cell and the cushioning material in the battery module of the present application. [Figure 16] 1 is a structural schematic diagram of a first embodiment of a cushioning material according to the present invention. [Figure 17] FIG. 10 is a structural schematic diagram of a second embodiment of the cushioning material of the present invention. [Figure 18] FIG. 10 is a structural schematic diagram of a third embodiment of the cushioning material of the present invention. [Figure 19] FIG. 10 is a structural schematic diagram of a fourth embodiment of the cushioning material of the present invention. [Figure 20] FIG. 10 is a structural schematic diagram of a fifth embodiment of the cushioning material of the present invention. [Figure 21] FIG. 10 is a structural schematic diagram of a sixth embodiment of the cushioning material of the present invention. [Figure 22] 1 is a structural schematic diagram of a cooling structure for a battery pack according to the present application; [Explanation of symbols]

[0040] The reference numerals in the drawings in the description of the invention are as follows: 1000 vehicles 100 batteries 200 Controller 300 motor 1 battery pack 10 Battery Module 20 Lower housing 30 Power Management Module 40 Cooling structure 50 Upper end cover 60 Housing protection bottom plate 201 Side member 202 Cross member 11 First battery cell 12 Second battery cell 13 Third battery cell 10a 1st battery cell row 10b 2nd battery cell row 10c 3rd battery cell row 10d 4th battery cell row 14 End plate 140 1st surface 141 Second surface 142 Middle section 143 Slope 144 Stopper part 15 Binding Belt 16 Cushioning material 160 frames 161 Support rib 400 Cooling Channels DETAILED DESCRIPTION OF THE INVENTION

[0041] The following detailed description will be given of the embodiments of the technical solution of the present application with reference to the drawings. The following embodiments are only used to more clearly explain the technical solution of the present application, and are merely examples, which do not limit the scope of protection of the present application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terms used herein are merely for the purpose of describing specific examples and are not intended to limit the scope of the present application. The terms "including" and "having" and their equivalents in the specification and claims of the present application and the description of the drawings above are intended to be non-exclusive.

[0043] In the description of the embodiments of the present application, the terms "first," "second," etc. are merely used to distinguish between different objects, and should not be understood as indicating or implying relative importance, or the quantity, specific order, or hierarchical relationship of the technical features shown. In the description of the embodiments of the present application, unless otherwise clearly limited, "plurality" means two or more.

[0044] References to "an embodiment" herein mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. Appearances of the term "embodiment" in various places in this specification do not necessarily refer to the same embodiment, nor do they refer to embodiments that are mutually exclusive, independent, or alternative to other embodiments. Those skilled in the art will understand, both explicitly and implicitly, that the embodiments described herein can be combined with other embodiments.

[0045] The term "and / or" in the description of the embodiments of the present application merely describes the relationship between related objects and indicates that three types of relationships can exist. For example, A and / or B can indicate three situations: A exists alone, A and B exist simultaneously, and B exists alone. In this specification, the symbol " / " generally indicates that the related objects before and after it are in an "or" relationship.

[0046] In describing the embodiments of the present application, the term "plurality" refers to two or more (including two); similarly, "multiple sets" refers to two or more (including two sets), and "plurality" refers to two or more (including two).

[0047] In describing the embodiments of the present application, the orientations or positional relationships indicated by terms such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" are based on the orientations or positional relationships shown in the drawings and are intended to make the embodiments of the present application easier to explain and simplify the description, and do not indicate or imply that the target devices or elements have a specific orientation or should be configured or operated in a specific orientation, and therefore should not be understood to limit the embodiments of the present application.

[0048] In describing the embodiments of the present application, unless otherwise clearly specified or limited, terms such as "attached," "connected," "connected," and "fixed" should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection. They may also refer to a mechanical connection or an electrical connection. They may also refer to a direct connection, an indirect connection via an intermediate medium, internal communication between two elements, or an interactive relationship between two parts. Those skilled in the art will be able to understand the specific meanings of the above terms in the embodiments of the present application according to specific circumstances.

[0049] At present, with the development of the market situation, the application of power batteries is becoming more and more widespread. Power batteries are not only used in energy storage power systems such as hydroelectric, thermal, wind and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars, as well as in military equipment and aerospace, etc. With the expansion of the application fields of power batteries, the demand for them in the market is also constantly increasing.

[0050] The inventors have noted that the insertion and desorption of ions into and from the positive and negative active materials during the charge and discharge cycles of a battery cell causes the cell to expand due to side reactions within the cell system, such as deposition, thickness buildup, and graphite sheet peeling. The expansion of a battery cell generally occurs on the surface with the largest area, and the degree of expansion is more severe along the centerline of the surface with the largest area, while the degree of expansion is less along the edges of the surface with the largest area. A battery pack generally has multiple battery cell rows, and the cumulative expansion of the multiple battery cell rows can cause serious compression deformation or even fracture of the battery cells themselves and the battery pack's double-sided packaging structure, which is detrimental to the safety of the battery pack itself. Furthermore, if the double-sided packaging structure is reinforced, the overall weight of the battery pack increases, reducing the energy density of the battery pack. The battery pack's packaging structure may include end plates on both sides of the battery module or a battery pack housing structure.

[0051] In addition, battery cells generate heat during charge and discharge cycles, and longer battery cells generally have poorer heat dissipation properties. Furthermore, the edges of a battery cell dissipate heat quickly and have low temperatures, while the areas closer to the center of the battery cell dissipate heat slowly and have high temperatures. Therefore, the polarization of the cold areas on both sides of the same battery cell is greater than the polarization of the hot area in the center. This results in different charge and discharge capacities at different locations on the same battery cell, which can lead to lithium deposition on the polar sheets in the cold areas, potentially resulting in safety hazards.

[0052] Furthermore, the battery pack must have sufficient rigidity to avoid breakage or rupture during use. For this reason, various reinforcing structures such as cross members and side members are generally installed inside the battery pack. While the reinforcing structures can improve the rigidity of the entire battery pack, the placement of the reinforcing structures occupies space within the battery pack, reducing the energy density of the battery pack.

[0053] Therefore, improving the energy density of a battery pack, strengthening the structural strength of the battery pack, increasing the degree of temperature uniformity of the battery pack, and improving the heat dissipation performance of the battery pack are all directions that research in the battery field is aiming for. By improving any one of the following, the overall performance of a battery pack can be improved.

[0054] In order to further improve the overall performance of the battery pack, the inventors have conducted extensive research and designed a battery module for the battery pack, the battery module including at least two battery cell rows stacked along the width direction of the battery cells, including a first battery cell row and a second battery cell row adjacent to each other, the first battery cell row and the second battery cell row collectively including a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells.

[0055] The novel battery module provided by the inventors forms a staggered structure in which the centerlines of the battery cells in adjacent battery cell rows are not aligned on the same line, thereby enhancing the rigidity of the battery module and reducing the need for reinforcing structures within the battery pack. Furthermore, the staggered structure also reduces the centerlines of the battery cells along the length of the surfaces with the largest areas between adjacent rows, reducing the cumulative degree of expansion of the battery cells and thereby reducing the pressure on the two-sided packaging structure of the battery pack.

[0056] In addition, using batteries of different lengths makes it easy to use batteries of different chemical systems, and batteries of different chemical systems have different energy densities, so it is easy to adjust the energy density by selecting the number and arrangement of batteries of different lengths.

[0057] Furthermore, by appropriately selecting the length of the batteries, a battery module having a staggered structure can be formed to have a regular structure such as a general rectangular structure, thereby maximizing space utilization within a limited space and improving energy density.

[0058] The battery cells disclosed in the embodiments of the present application can be used in, but are not limited to, power consumption devices such as vehicles, ships, and aircraft, etc. The battery cells, batteries, etc. disclosed in the present application can be used to configure a power supply system for the power consumption device.

[0059] An embodiment of the present application provides a battery-powered power consumption device, which may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric vehicle, a boat, a spacecraft, etc. The electric toy may include a stationary or mobile electric toy such as a game console, an electric toy car, an electric toy boat, and an electric toy aircraft, and the spacecraft may include an aircraft, a rocket, a space shuttle, a spaceship, etc.

[0060] In the following embodiments, for convenience of explanation, the power consumption device of the embodiment of the present application will be described as a vehicle 1000.

[0061] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, a range-extender vehicle, etc. A battery 100 is installed inside the vehicle 1000, and the battery 100 may be installed at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to supply power to the vehicle 1000, for example, as an operating power source for the vehicle 1000. The vehicle 1000 can further include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the operating power needs for starting, navigation, and driving the vehicle 1000.

[0062] In some embodiments of the present application, the battery 100 can provide not only the operating power source for the vehicle 1000 but also the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0063] 2, which is a schematic exploded view of a typical battery pack used in a vehicle. The battery pack 1 includes a battery module 10, a lower housing 20, a power management module 30, a cooling structure 40, an upper end cover 50, and a housing protective bottom plate 60.

[0064] The lower housing 20 and the upper end cover 50 are fitted together to provide a storage space for the battery module 10. The lower housing 20 may have a hollow structure with one end open, and the upper end cover 50 may have a plate-like structure, with the upper end cover 50 covering the open side of the lower housing 20 so that the lower housing 20 and the upper end cover 50 together define the storage space. For example, the lower housing 20 and the upper end cover 50 may both have a hollow structure with one end open, with the open side of the lower housing 20 covering the open side of the upper end cover 50. The housing formed by the lower housing 20 and the upper end cover 50 may have various shapes, such as a cylinder or a rectangular parallelepiped.

[0065] The battery module 10 includes multiple battery cells. The battery cells may be multiple, and the multiple battery cells 20 may be connected in series, parallel, or series-parallel. A series-parallel connection refers to not only a series connection but also a parallel connection of the multiple battery cells. The multiple battery cells may be directly connected in series, parallel, or series-parallel, and then the entire configuration of the multiple battery cells may be housed within the lower housing 20. The battery module 10 may be configured by first connecting multiple battery cells in series, parallel, or series-parallel to form a battery module, and then multiple battery modules may be further connected in series, parallel, or series-parallel to form an integrated battery module and housed within the lower housing 20. The battery pack 1 may include other structures, such as a bus member for electrically connecting the multiple battery cells.

[0066] Each battery cell may be a secondary battery or a primary battery, and may be, but is not limited to, a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery. The battery cells may be flat, rectangular, or have other shapes.

[0067] The power management module 30 can be disposed inside the lower housing 20, for example, in the front end of the lower housing 20. The power management module 30 can supply power to the battery cells in the battery pack and can monitor various data of the battery pack, such as voltage monitoring, current monitoring, temperature monitoring, insulation monitoring, and charge state monitoring, and can obtain the voltage, current, temperature, charge state, etc. as thermal runaway detection data.

[0068] The cooling structure 40 is arranged below the lower housing 20, and a cooling flow path is provided inside the cooling structure 40, and a coolant can be flowed through the cooling flow path to cool the battery pack 1 and lower its temperature.

[0069] The housing protection bottom plate 60 is disposed below the cooling structure 40 to protect the lower housing 20 and protect the battery pack 1 from damage, for example, due to an impact from below. The housing protection bottom plate, the lower housing, and the upper end cover may be made of copper, iron, aluminum, stainless steel, an aluminum alloy, or the like, and the present application is not particularly limited thereto.

[0070] 2, side members 201 and cross members 202 are installed inside the lower housing 20, and the side members and cross members are respectively disposed between the battery modules 10 and are used to increase the overall rigidity of the battery pack 1. In FIG. 2, one cross member 202 and two side members 201 are used to define the accommodation space for the six battery modules 10.

[0071] Based on some embodiments of the present application, referring to FIG. 3 and further to FIGS. 4 to 12, there are schematic top view structures of different embodiments of the battery pack 1 of the present application, in which the upper end cover 50 of the battery pack 1 is removed to more clearly show the arrangement of the battery modules 10.

[0072] FIG. 3 shows a first embodiment of a battery module 10, in which the battery module 10 includes at least two adjacent battery cell rows, including a first battery cell row 10a and a second battery cell row 10b, stacked along the width direction of the battery cells. The first battery cell row 10a and the second battery cell row 10b collectively include a plurality of battery cells, some battery cells 11 of the plurality of battery cells having a different length compared to the remaining battery cells 12. Along the width direction of the battery cells, the center line of the length direction of at least one battery cell 11 in the first battery cell row 10a is not on the same line as the center line of the length direction of at least one battery cell 12 in the second battery cell row 10b.

[0073] The battery cell has a rectangular prism housing structure and six surfaces. The "width direction" is the x-direction in FIG. 2, which is perpendicular to the two largest opposing surfaces of the battery cell. The "length direction" is the y-direction in FIG. 2, which is parallel to the two largest opposing surfaces of the battery cell. The "center line of the battery cell in the length direction" is a line extending through the center of the two largest opposing surfaces of the battery cell along the x-direction. The "width direction" and "length direction" are perpendicular to each other. The "height direction" is perpendicular to the "width direction" and "length direction." In some embodiments, the battery cell includes a top cover and a housing, and the top cover and the bottom wall of the housing are arranged opposite each other in the "height direction." However, the positions and structures of the top cover and the housing are not limited thereto.

[0074] As shown in Figure 3, the longitudinal centerline of at least one battery cell 11 in the first battery cell row 10a and the longitudinal centerline of at least one battery cell 12 in the second battery cell row 10b are not aligned, so that the center of the largest-area surface of at least one battery cell 11 is offset from the center of the largest-area surface of at least one battery cell 12. Battery cells expand during repeated charge / discharge cycles, and the expansion is most severe in the center of the largest-area surface and less at the edges of the battery cells. Therefore, if the centers of the largest-area surfaces of battery cells in adjacent rows are aligned widthwise, the expansion of the centers of the largest-area surfaces will accumulate, worsening the overall expansion of the entire battery module 10 and causing serious compression of the packaging structure on both sides of the battery pack. By aligning the center of the largest-area surface of at least one battery cell 11 so that the center of the largest-area surface of at least one battery cell 12 is offset, the overall expansion of the battery pack can be effectively alleviated.

[0075] Furthermore, by arranging the at least one battery cell 11 so that the center of the surface with the largest area is offset from the center of the surface with the largest area of ​​the at least one battery cell 12, an effective staggered structure can be formed, and the staggered structure itself provides increased rigidity to the battery module 10 and effectively reduces the need for cross members in the battery pack. As can be seen from comparing Figures 2 and 3, the battery pack of the present application does not use cross members 202, which further improves the space utilization rate of the battery pack 1 and increases the capacity of the battery pack 1.

[0076] 4 to 12 show second to tenth embodiments of the battery module 10. Each of the second to tenth embodiments of the battery module 10 includes at least two adjacent battery cell rows, including a first battery cell row 10a and a second battery cell row 10b, that are stacked along the width direction of the battery cells, and the first battery cell row 10a and the second battery cell row 10b collectively include a plurality of battery cells, some of which have a different length compared to the remaining battery cells, so that the center line in the length direction of at least one battery cell in the first battery cell row 10a and the center line in the length direction of at least one battery cell in the second battery cell row 10b are not on the same line along the width direction of the battery cells.

[0077] Some of the battery cells shown in the first to tenth embodiments of the battery module 10 are elongated rectangular parallelepipeds, some are general rectangular parallelepiped batteries, and some are cubic batteries.

[0078] The differences among the first to tenth embodiments of the battery module 10 are mainly in the size of the battery cells included in each embodiment and in the combination and arrangement of the battery cells in adjacent rows. Other than that, the structures of the first to tenth embodiments of the battery module 10 are substantially the same, and therefore, hereinafter, a description of the overlapping parts between different embodiments will be omitted. For example, in the first embodiment of the battery module 10 in FIG. 3, the third embodiment of the battery module 10 in FIG. 5, the sixth embodiment of the battery module 10 in FIG. 8, the seventh embodiment of the battery module 10 in FIG. 9, the ninth embodiment of the battery module 10 in FIG. 11, and the tenth embodiment of the battery module 10 in FIG. 12, the width of the first battery cell 11 is the same as the width of the second battery cell 12, but the length is twice that of the second battery cell 12. In the second embodiment of the battery module 10 in FIG. 4, the fourth embodiment of the battery module 10 in FIG. 6, and the fifth embodiment of the battery module 10 in FIG. 7, the length of the first battery cell 11 is twice the length of the second battery cell 12, and the width of the second battery cell 12 is twice the width of the first battery cell 11. The size relationships between different battery cells in the present application are not limited to integer relationships; for example, the length of the first battery cell 11 in the eighth embodiment of the battery module 10 in FIG. 10 is 1.5 times the length of the second battery cell 12. They are also not limited to the ten size relationships disclosed in the embodiments of FIGS. 3 to 12; FIGS. 3 to 12 merely disclose some possible embodiments in an exemplary manner, and the present application is not particularly limited thereto.

[0079] Referring again to FIG. 3, the first battery cell row 10a and the second battery cell row 10b have the same overall length, and the edges of the first battery cell row 10a and the second battery cell row 10a in the length direction are flush with each other.

[0080] The "longitudinal edges of the battery cells" refer to the side edges of adjacent battery cell rows that extend along the x-direction. "Flush" refers to the longitudinal edges of adjacent battery cell rows that are collinear along the x-direction.

[0081] Since adjacent battery cell rows have the same overall length and their edges along the length are flush, the battery module 10 can be formed into a rectangular prism, such as a rectangular parallelepiped or cube. Generally, the battery pack frame of the battery pack 1 and the storage space for the battery module 10, surrounded by the battery pack frame and side members, have a rectangular prism shape, which reduces the processing cost of the battery pack, maximizes the space, and facilitates installation of the battery pack. Therefore, in this case, the battery module 10 formed into a rectangular prism can further improve the utilization rate of the storage space of the battery pack 1 and further improve the energy density of the battery.

[0082] The second to tenth embodiments of the battery module 10 shown in FIGS. 4 to 12 are also formed in a regular quadrangular prism shape.

[0083] Referring again to FIG. 3, along the width direction of the battery cells, the longitudinal center line of each battery cell 11 in the first battery cell row 10a and the longitudinal center line of each battery cell 12 in the second battery cell row 10b are not on the same line.

[0084] By arranging the battery cells in adjacent battery cell rows so that none of them are collinear, a more robust staggered structure can be formed and the accumulation of expansion at the center of the surface with the largest area of ​​each battery cell in the adjacent battery cell rows can be further reduced.

[0085] The center line in the longitudinal direction of each battery cell in the first battery cell row 10a of the second to tenth embodiments of the battery module 10 shown in Figures 4 to 12 is not on the same line as the center line in the longitudinal direction of each battery cell in the second battery cell row 10b. As mentioned above, one of the differences between the second to tenth embodiments of the battery module 10 is the relative sizes of the battery cells included in each embodiment.

[0086] Furthermore, the lengths of the first battery cells 11 and the second battery cells 12 of the first to tenth embodiments of the battery modules 10 shown in FIGS. 3 to 12 of the present application are all different.

[0087] Generally, the longer the length of a battery cell, the lower the heat dissipation effect but the stronger the structural rigidity. Therefore, by combining battery cells of different lengths, it is possible to ensure structural rigidity while achieving acceptable or good heat dissipation effect, thereby achieving a good balance and improvement between the structural rigidity and overall heat dissipation of the battery pack.

[0088] Referring again to FIG. 3, in the first embodiment of the battery module 10 shown in FIG. 3, the first battery cell column 10a is configured by first battery cells 11 arranged along the length, and the second battery cell column 10b is configured by second battery cells 12 arranged along the length. Specifically, the first battery cell column 10a is configured by one first battery cell 11 arranged along the length, and the second battery cell column 10b is configured by two second battery cells 12 arranged along the length. For example, the first battery cell column 10a may be configured by multiple first battery cells 11 arranged along the length, and the second battery cell column 10b may be configured by one or more second battery cells 12 arranged along the length. The number of battery cells in each column can be selected as needed, and this is the same for all of the embodiments in FIGS. 4 to 12 below, so detailed description thereof will be omitted.

[0089] The first battery cell 11 in Figure 3 is a length-extended battery, and because the length-extended battery itself is longer, its rigidity is higher than that of the second battery cell 12. In Figure 3, the first battery cell string 10a is composed of one first battery cell 11, so the length-extended battery extends throughout the entire length of the battery pack 1 (i.e., the y direction in Figure 2), and the length-extended battery itself serves to strengthen the rigidity. In addition, by combining the length-extended battery and regular batteries in a staggered pattern, the overall structural strength of the battery pack can be further improved, and a cross member extending in the length direction of the battery cells in the battery pack in Figure 3 can be omitted.

[0090] In the different embodiments shown in Figures 4, 8, 9, 10, and 11, the first battery cell row 10a is configured by battery cells of one type being arranged along the length direction, and the second battery cell row 10b is configured by battery cells of another type being arranged along the length direction. For example, in the different embodiments shown in Figures 4, 8, 9, 10, and 11, the number of battery cells arranged in each battery cell row is not limited to the numbers shown in the figures, and a different number of battery cells can be arranged as needed.

[0091] 6, in the fourth embodiment of the battery module 10 shown in Fig. 6, the first battery cell row 10a is configured by arranging first battery cells 11 along the length direction, and the second battery cell row 10b is configured by arranging first battery cells 11 and second battery cells 12 along the length direction. Specifically, in Fig. 6, the first battery cell row 10a includes two first battery cells 11, and the second battery cell row 10b includes two first battery cells 11 and two second battery cells 12, and the two first battery cells 11 are located between the two second battery cells 12.

[0092] Therefore, this provides an alternative means for selecting and arranging different battery cells in the battery module 10, and still, the staggered structure can achieve advantages such as strengthening the structural strength, alleviating the accumulation of battery expansion units in the battery pack by shifting the center of the surface with the largest area, and improving the space utilization rate and the energy density of the battery.

[0093] 5, in a third embodiment of a battery module 10 shown in Fig. 5, a first battery cell column 10a includes first battery cells 11 and second battery cells 12 arranged in a first order along the length, and a second battery cell column 10b includes first battery cells 11 and second battery cells 12 arranged in a second order along the length, where the first order and the second order are different. Specifically, in Fig. 5, the first battery cell column 10a includes one first battery cell 11 and one second battery cell 12, and the first order is one second battery cell 12 and one first battery cell 11 arranged in order from left to right. The second battery cell column 10b also includes one first battery cell 11 and one second battery cell 12, but the second order is one first battery cell 11 and one second battery cell 12 arranged in order from left to right.

[0094] 7, the first battery cell column 10a has the second battery cell 12 and the first battery cell 11 arranged in that order from left to right, and the second battery cell column 10b has the first battery cell 11 and the second battery cell 12 arranged in that order from left to right. The first battery cell column 10a and the second battery cell column 10b have the same battery configuration but different arrangement orders.

[0095] This also therefore provides a desirable alternative for selecting and arranging different battery cells within the battery module 10.

[0096] Referring to FIG. 7 , the first battery cell row 10a includes single or multiple layered first battery cells 11 arranged along the width direction of the battery cells and single or multiple layered second battery cells 12 arranged along the width direction of the battery cells, and the single or multiple layered first battery cells 11 and the single or multiple layered second battery cells 12 are arranged along the length direction of the battery cells, and although the number of layers of the first battery cells 11 and the number of layers of the second battery cells 12 are different, the overall widths of the single or multiple layered first battery cells 11 and the single or multiple layered second battery cells 12 are the same. Specifically, in FIG. 7, the first battery cell row 10a includes one layer of second battery cells 12 and two layers of first battery cells 11, the width of the second battery cells 12 is twice that of the first battery cells 11, and along the width direction of the battery cells, the two layers of first battery cells 11 are located to the right of the one layer of second battery cells 12, and along the width direction of the battery cells, the two layers of first battery cells 11 in the second battery cell row 10b are located to the left of the one layer of second battery cells 12, which also forms a staggered structure.

[0097] This also therefore provides a desirable alternative for selecting and arranging different battery cells within the battery module 10.

[0098] 6, the second battery cell row 10b includes one or more layers of first battery cells 11 arranged along the width direction of the battery cells of the battery module, and one or more layers of second battery cells 12 arranged along the width direction of the battery cells, and the one or more layers of first battery cells 11 and the one or more layers of second battery cells 12 are arranged along the length direction of the battery cells, and the number of layers of the first battery cells 11 and the number of layers of the second battery cells 12 are different, but the overall widths of the one or more layers of first battery cells 11 and the one or more layers of second battery cells 12 are the same. Specifically, in FIG. 6, the second battery cell row 10b includes one layer of second battery cells 12 and two layers of first battery cells 11, and the two layers of first battery cells 11 are located between two second battery cells 12 along the length direction of the battery cells. As described above, FIG. 7 shows a structure in which the second battery cell string 10b includes one or more layers of first battery cells 11 and one or more layers of second battery cells 12, with the number of layers varying depending on the battery cells.

[0099] This also therefore provides a desirable alternative for selecting and arranging different battery cells within the battery module 10.

[0100] 12, the tenth embodiment of the battery module 10 shown in Fig. 12 further includes a third battery cell 13, and the third battery cell 13, the first battery cell 11, and the second battery cell 12 have different lengths. The first battery cell row 10a is configured by arranging the first battery cells 11 along the length direction, and the second battery cell row 10b includes single- or multi-layered second battery cells 12 arranged along the width direction of the battery cells and single- or multi-layered third battery cells 13 arranged along the width direction of the battery cells, and the single- or multi-layered second battery cells 12 and the single- or multi-layered third battery cells 13 are arranged along the length direction of the battery cells, and the number of layers of the second battery cells 12 and the number of layers of the third battery cells 13 are different, but the overall widths of the single- or multi-layered second battery cells 12 and the single- or multi-layered third battery cells 13 are the same. Specifically, in FIG. 12, the first battery cell row 10a includes one first battery cell 11, the second battery cell row 10b includes two layers of second battery cells 12 and one layer of third battery cells 13, and along the length direction of the battery cells, the two layers of second battery cells 12 are located between two third battery cells 13.

[0101] This also therefore provides a desirable alternative for selecting and arranging different battery cells within the battery module 10.

[0102] 8, the sixth embodiment of the battery module 10 shown in Fig. 8 further includes a third battery cell row 10c, which is adjacent to the second battery cell row 10b in the width direction, and the arrangement of the battery cells in the third battery cell row 10c is the same as the arrangement of the battery cells in the second battery cell row 10b. In Fig. 8, the second battery cell row 10b and the third battery cell row 10c are both composed of first battery cells 11, and the first battery cell row 10a is composed of second battery cells 12. Specifically, the second battery cell row 10b and the third battery cell row 10c each include one first battery cell 11, and the first battery cell row 10a includes two second battery cells 12.

[0103] Seventh to tenth embodiments of the battery module 10 shown in Figures 9 to 12 also disclose a third battery cell row 10c. In Figures 9 to 12, each third battery cell row 10c is adjacent to the first battery cell row 10a along the width direction of the battery cells, and the arrangement of the third battery cell row 10c is the same as that of the adjacent first battery cell row 10a. One difference between the different embodiments of the battery module 10 shown in Figures 9 to 12 is the size and number of battery cells included in each embodiment.

[0104] 11 further includes a fourth battery cell row 10d, which is adjacent to the second battery cell row 10b in the width direction of the battery cells, and the battery cells of the fourth battery cell row 10d are arranged in the same manner as the adjacent second battery cell row 10b. That is, in FIG. 11, the third battery cell row 10c, the first battery cell row 10a, the second battery cell row 10b, and the fourth battery cell row 10d are arranged in this order in the width direction of the battery cells.

[0105] That is, the battery module in the present application may include one or more additional battery cell rows in addition to the first battery cell row and the second battery cell row, and the one or more battery cell rows may be adjacent to the first battery cell row or the second battery cell row, and the arrangement of the battery cells in the one or more battery cell rows may be the same as the arrangement of the battery cells in the first battery cell row or the second battery cell row.

[0106] This also therefore provides a desirable alternative for selecting and arranging different battery cells within the battery module 10.

[0107] Referring again to Fig. 3, the first embodiment of the battery module 10 in Fig. 3 includes a plurality of first battery cell rows 10a and second battery cell rows 10b arranged alternately along the width direction of the battery cells. Specifically, the battery module 10 in Fig. 3 includes a total of ten first battery cell rows 10a and second battery cell rows 10b arranged alternately. Different embodiments shown in Figs. 4 to 7 also show a plurality of first battery cell rows 10a and second battery cell rows 10b arranged alternately along the width direction of the battery cells in the battery module 10.

[0108] The different embodiments of the battery module 10 shown in Figures 8, 9, 10, and 12 include a plurality of first, second, and third battery cell rows 10a, 10b, and 10c battery cell rows arranged alternately along the width direction of the battery cells. The ninth embodiment of the battery module 10 shown in Figure 11 includes a plurality of first, second, third, and fourth battery cell rows 10a, 10b, 10c, and 10d battery cell rows arranged alternately along the width direction of the battery cells. Furthermore, unless otherwise specified, the terms "first," "second," "third," and "fourth" do not imply any chronological order but merely serve to distinguish between different terms. Furthermore, unless an order of arrangement is clearly specified, the description of each battery cell row does not imply that the rows must be arranged in the chronological order of the description.

[0109] By arranging a plurality of battery cell rows in an alternating arrangement, the effect of the staggered arrangement can be further enhanced and the battery energy can be further improved.

[0110] Referring again to FIG. 3, in the first embodiment of the battery module 10 of FIG. 3, the length of the first battery cell 11 is longer than the length of the second battery cell 12, specifically twice the length of the second battery cell 12. Also, along the width direction of the battery cells in FIG. 3, the longitudinal centerline of the first battery cell 11 in the first battery cell row 10a substantially faces one sidewall of one of the second battery cells 12 in the second battery cell row. As described above, the degree of expansion of a battery cell is smallest at the sidewall portion and largest at the longitudinal centerline or the center of the surface with the largest area. Therefore, this arrangement can minimize cumulative expansion in the battery pack. Similar structures are shown in different embodiments of the battery module 10 shown in FIGS. 4 to 11.

[0111] In the present application, the use of battery cells of different lengths facilitates the use of battery cells of different chemical systems. For example, in the above embodiment, the positive electrode active materials of the first battery cell 11, the second battery cell 12, and / or the third battery cell 13 may be different.

[0112] In some embodiments, the positive electrode active material can be a known positive electrode active material for batteries. The positive electrode material can be lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium vanadium oxide, manganese nickel cobalt composite oxide, nickel cobalt aluminum composite oxide, transition metal oxide, polyanion compound, Prussian blue compound, or the like. For example, the positive electrode active material can include at least one of a lithium-containing phosphate with an olivine structure, a lithium transition metal oxide, and a modified compound thereof. However, the present application is not limited to these materials, and other conventional materials usable as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination. Examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO), lithium nickel oxide (e.g., LiNiO), lithium manganese oxide (e.g., LiMnO, LiMnO), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (e.g., LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (abbreviated as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (abbreviated as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (abbreviated as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (abbreviated as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (abbreviated as NCM 811 )), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.85 Co 0.15 Al 0.05O2) and modified compounds thereof, etc. The lithium-containing phosphate having an olivine structure may include, but is not limited to, for example, at least one of lithium iron phosphate (e.g., LiFePO4 (abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0113] In addition, battery cells of different lengths may have different energy densities. For example, some battery cells have low energy density / specific capacity, such as sodium-ion batteries, lithium iron phosphate batteries, and lithium manganese oxide batteries, while other battery cells have high energy density / specific capacity, such as ternary NCM or NCA batteries and lithium metal batteries. Using battery cells with different chemistries makes it easier to customize the energy density of a battery module.

[0114] Using different positive electrode active materials for the first battery cell 11, the second battery cell 12, and / or the third battery cell 13—for example, using ternary batteries for one or two types of battery cells and lithium iron phosphate batteries for the other one or two types—reduces the cost of the entire battery module and the entire battery pack comprising the lithium iron phosphate batteries. Furthermore, their resistance to thermal runaway improves the safety of the battery pack. For example, even if a thermal runaway occurs in a ternary battery, the lithium iron phosphate batteries act as a barrier to maintain the safety of the entire battery module and battery pack. At the same time, using ternary batteries ensures the battery module and battery pack have good performance. Furthermore, taking advantage of the different curve characteristics of ternary batteries and lithium iron phosphate batteries improves the accuracy of measuring the state of charge of the battery pack.

[0115] 3 to 12, each of the embodiments of the battery module 10 shown in FIGS. 3 to 12 includes an end plate 14. The end plates 14 are installed in pairs, and each end plate 14 is disposed at each end of the battery module 10 along the width direction of the battery cell. Referring to FIG. 13, FIG. 13 shows a schematic structural diagram of a pair of end plates 14. The end plate 14 includes a first surface 140 and a second surface 141. The first surface 140 is closer to the battery unit and is disposed to contact the battery unit when assembled together with the battery unit, while the second surface 141 is farther from the battery unit and is disposed to face the first surface 140 along the width direction of the battery unit when assembled together with the battery unit. The first surface 140 is formed as a flat surface to ensure firm contact with the battery unit. The second surface 141 includes a middle portion 142 and two inclined portions 143. The inclined portions 143 are disposed on both sides of the middle portion 142 along the vertical direction of the end plate (i.e., the up-and-down direction in FIG. 13 ) and are inclined from the middle portion 142 toward the first surface 140. The end plate may be made of an aluminum alloy, a polymer plastic, or the like, but the present application is not limited thereto. In addition, the end plate 14 is formed with a hollow structure, which can further reduce the weight of the end plate and the entire battery module while ensuring basic structural strength.

[0116] Therefore, the end plate 14 is formed with a structure that is thick in the center and thin on both sides. The greater structural strength in the center allows for greater resistance to deformation of the end plate due to expansion of the surface at the center of the battery, which has the largest area. The provision of sloped portions on both sides makes binding easier. When assembling a pair of end plates and multiple battery cells, it is even easier to cross binding belts to bind them together.

[0117] 13, the end plate 14 further includes a pair of two stopper portions 144. Each stopper portion 144 is provided on the side of the inclined portion 143 farther from the intermediate portion 142, i.e., on the end portion along the vertical direction of the end plate 14. The thickness of the stopper portion 144 is formed to be greater than the thickness of the inclined portion 143 on the side adjacent to it.

[0118] The stopper portion 144 can prevent the tie belt from falling off the end plate 14 when binding using the tie belt.

[0119] 14, which shows a side view of a battery module 10, in which a plurality of alternating first and second battery cell rows 10a, 10b and pairs of end plates 14 on both sides are bound together with binding belts 15 to form the battery module 10. As can be seen from FIG. 14, the vertical direction of the end plates 14 corresponds to the height direction of the battery module. The binding belts 15 are provided around the outer periphery of the battery modules 10 and bind them diagonally, i.e., one side is connected to an inclined portion 143 located on the upper side of one end plate 14 and the other side is connected to an inclined portion 143 located on the lower side of the opposing end plate 14.

[0120] Since the binding belt is generally a steel belt or a polymer nylon belt and is lightweight, the weight of the assembled battery module can be further reduced by assembling the battery module 10 using the binding belt. Furthermore, by binding the battery module 10 at an angle using the binding belt, the binding force can be applied to the battery module 10 over the entire range from the upper inclined portion to the lower inclined portion, so that the force received by the battery module 10 is more uniform and the battery module 10 is bound more firmly.

[0121] 14 also shows two tie belts 15, which are crossed for binding. By crossing and binding, the force applied to the battery module 10 is more uniform, ensuring that the upper and lower parts of the battery module receive the same expansion force when the battery module expands. This prevents the battery from receiving excessive force locally due to differences in expansion force, which can lead to lithium deposition.

[0122] Furthermore, the mutual combination of the binding belt and the end plate can further strengthen the overall structural rigidity of the battery pack, further reducing the need for reinforcing members in the battery pack.

[0123] FIG. 15 is a schematic exploded view of the battery cells and buffer material in a battery module according to the present invention. The battery cell arrangement in FIG. 15 corresponds to the first embodiment of the battery module 10 in FIG. 3. The buffer material 16 is arranged between the first and second battery cell rows 10a and 10b along the width direction of the battery cells. The thickness of the buffer material may be 0.5 to 3 mm. FIG. 16 shows a first embodiment of the buffer material 16. The area of ​​the buffer material 16 can be slightly smaller than the area of ​​the largest surface of the first battery cell 11. By providing the buffer material between two adjacent battery cell rows, the expansion force of the battery can be absorbed when the largest surface of the battery cell in the module expands. The buffer material 16 includes a frame 160 and a hollow structure formed within the frame. The hollow structure provides additional buffer space when the largest surface of the battery cell in the module expands, thereby reducing the accumulation of expansion force. In addition, insulating wool may be provided in the hollow structure, which can mitigate expansion and at the same time play a role in keeping warm and insulating.

[0124] Fig. 17 shows a second embodiment of the cushioning material 16. In Fig. 17, the cushioning material 16 includes a frame 160 and a support rib 161 provided inside the frame 160. A hollow structure is formed between the frame 160 and the support rib 161, and faces not only the surface with the largest area of ​​the first battery cell 11 in the first battery cell row 10a, but also the surface with the largest area of ​​the second battery cell 12 in the second battery cell row 10b.

[0125] By providing the support ribs, the structural rigidity of the cushioning material can be improved, and it is possible to prevent the center of the frame from bending downward due to gravity due to the cushioning material being too thin.

[0126] The second embodiment of the cushioning material 16 in Fig. 17 corresponds to the cushioning material in Fig. 15 and can be applied to the first embodiment of the battery module 10 shown in Fig. 3. The support rib 161 is positioned so as to correspond to the center of the surface with the largest area of ​​the first battery cell 11 in the first battery cell row 10a, i.e., so as to correspond to one edge of the second battery cell 12 in the second battery cell row 10b.

[0127] In this application, because battery cells of different lengths are installed in a staggered pattern, the centers of the largest-area surfaces of battery cells in adjacent rows are offset from each other, and the center of the largest-area surface of a battery cell in one row abuts the edge of a battery cell in an adjacent row. The edges of the battery cells form corners, and if the center of the largest-area surface expands and abuts the corners, the force applied to the center of the largest-area surface will be too great, and the center of the largest-area surface may be damaged as the battery cells are repeatedly charged and discharged and the degree of expansion accumulates. By arranging the support ribs so that they correspond to the edges of the battery cells, the risk of damage to the largest-area surface of the battery cells can be reduced.

[0128] FIGS. 18 to 21 are structural schematic diagrams of third to sixth embodiments of the cushioning material of the present invention. The different embodiments of the cushioning material differ in the number and position of the support ribs. The cushioning material can be selected to correspond to the different embodiments of the battery module 10 in FIGS. 3 to 12. For example, the second embodiment of the cushioning material in FIG. 17 can be provided between the first and second battery cell rows 10a and 10b of the battery module 10 in FIGS. 3, 8, 9, and 11. The third embodiment of the cushioning material in FIG. 18 can be provided between the first and second battery cell rows 10a and 10b of the battery module 10 in FIGS. 5 and 7. The fourth embodiment of the cushioning material in FIG. 19 can be provided between the first and second battery cell rows 10a and 10b of the battery module 10 in FIG. 12. The fifth embodiment of the cushioning material in FIG. 20 can be provided between the first and second battery cell rows 10a and 10b of the battery module 10 in FIGS. 4 and 6. A sixth embodiment of the cushioning material in Fig. 21 can be provided between the first battery cell row 10a and the second battery cell row 10b of the battery module 10 in Fig. 10. This allows the support ribs to accommodate all edges that may come into contact with the largest surface of the adjacent battery cell row, thereby avoiding damage that may result from contact with the edge when the largest surface expands.

[0129] According to some embodiments of the present application, the present application further provides a battery pack 1 including a lower housing 20 and any of the embodiments of the battery module 10. Referring to Figs. 3 to 12, at least one battery module row is housed in the lower housing, and each battery module row includes a plurality of battery modules 10 arranged along the width direction of the battery cells. The battery modules in the row may be fixed to the bottom of the lower housing by a thermally conductive adhesive or the like.

[0130] 3 to 12, the battery pack 1 includes at least two rows of the battery modules, and a side member 201 is provided between two adjacent rows of battery modules. When the rows of battery modules are initially assembled, a gap of 1 to 3 mm is left between adjacent battery modules, i.e., the end plates of adjacent battery modules are not in direct contact with each other, and a gap of 1 to 3 mm is left, which provides room for buffering against expansion of the battery pack.

[0131] FIG. 22 shows a structural schematic diagram of a cooling structure 40 for a battery pack according to the present invention. The cooling structure 40 is installed below the frame of the battery pack and cools through a cooling channel 400. The cooling channel 400 extends in a circuitous manner along the width of the battery cells and is used to allow a cooling fluid to flow. The battery cells in the battery pack generate heat during repeated charging and discharging, and the cooling fluid is used to prevent the temperature of the battery pack from becoming too high. The cooling channel 400 extends in a circuitous manner along the width of the battery cells, i.e., it is formed in a serpentine shape as shown in FIG. 22. As shown in FIG. 22, the cooling channel 400 extends parallel to the length of the battery cells and is circuitous in the width direction, thereby increasing the contact area between the bottom of the battery cells and the cooling channel, improving heat dissipation, and further improving the bending resistance of the battery pack in the width direction of the battery cells.

[0132] The cooling structure 40 may be formed in a plate shape. The cooling structure 40 may be formed of a metal with excellent thermal conductivity, such as copper, iron, aluminum, stainless steel, or an aluminum alloy, but the present application is not particularly limited thereto.

[0133] Furthermore, the cross-sectional area of ​​the cooling channel 400 is not constant, and the cross-sectional area of ​​the cooling channel 400 in the middle of the battery module 10 is larger along the width direction of the battery cell than in other parts of the battery module 10. By designing the cooling channel 400 to have a larger cross-sectional area in the middle, heat dissipation in the middle of the battery pack can be improved. Regarding the temperature distribution of the battery pack, since the center is higher than the edge, uneven temperature distribution can exacerbate differences in the charge / discharge characteristics of different battery cells and can also lead to safety hazards such as lithium precipitation. In contrast, the present invention allows the cross-sectional area of ​​the cooling channel to vary, thereby further uniforming the temperature of the battery pack.

[0134] According to some embodiments of the present application, the present application further provides a power consuming device including any of the embodiments of the battery pack described above used to supply electrical energy.

[0135] The power consuming device may be any of the devices or systems described above that use a battery.

[0136] According to some embodiments of the present application, the present application provides: providing a plurality of battery cells, some of the battery cells having a different length compared to the remaining battery cells; the plurality of battery cells are arranged in at least two battery cell rows along a width direction of the battery cells, the at least two battery cell rows including a first battery cell row and a second battery cell row adjacent to each other; and arranging the battery cells so that a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells.

[0137] Finally, the following points should be mentioned: The above embodiments are merely for illustrating the technical solutions of the present application, and are not intended to limit the same. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand the following: The technical solutions described in the above embodiments may still be modified, or some or all of the technical features therein may be equivalently substituted, and such modifications or substitutions do not cause the substance of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and all of them should be encompassed by the scope of the claims and the description of the present application. In particular, the technical features mentioned in the embodiments may be combined in any way as long as there is no structural contradiction. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions encompassed by the claims.

Claims

1. the battery cell assembly includes at least two battery cell rows including a first battery cell row and a second battery cell row that are stacked along a width direction of the battery cells and adjacent to each other, the first battery cell row and the second battery cell row collectively including a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells; The battery pack includes a plurality of sets of the at least two battery cell rows arranged in a stack, the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the first battery cell row is configured by arranging first battery cells along a length direction, and the second battery cell row is configured by arranging first battery cells and second battery cells along a length direction; Battery module.

2. A battery cell assembly including at least two battery cell rows stacked along the width direction of the battery cells and including adjacent first and second battery cell rows, the first and second battery cell rows collectively including a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and the longitudinal center line of at least one battery cell in the first battery cell row and the longitudinal center line of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells, The battery pack includes a plurality of sets of the at least two battery cell rows arranged in a stack, the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the first battery cell row is configured by arranging first battery cells and second battery cells in a first arrangement order along a length direction, and the second battery cell row is configured by arranging first battery cells and second battery cells in a second arrangement order along a length direction, the first arrangement order and the second arrangement order being different; Battery module.

3. A battery cell assembly comprising at least two battery cell rows, including a first battery cell row and a second battery cell row, stacked along the width direction of the battery cells and adjacent to each other, the first battery cell row and the second battery cell row collectively comprising a plurality of battery cells, some of the plurality of battery cells having a different length compared to the remaining battery cells, and a longitudinal center line of at least one battery cell in the first battery cell row and a longitudinal center line of at least one battery cell in the second battery cell row are not on the same line along the width direction of the battery cells, The battery pack includes a plurality of sets of the at least two battery cell rows arranged in a stack, the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the plurality of battery cells further includes third battery cells having a length different from that of the first battery cells and the second battery cells, the first battery cell row is configured by arranging the third battery cells along a length direction, the second battery cell row includes m layers of first battery cells arranged along a width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, the m layers of first battery cells and the n layers of second battery cells are arranged along the length direction of the battery cells, m and n are different, and the m layers of first battery cells and the n layers of second battery cells have the same width; Battery module.

4. 4. The battery module according to claim 1, wherein the first battery cell row and the second battery cell row have the same overall length, and longitudinal edges of the first battery cell row and the second battery cell row are flush with each other.

5. 4. The battery module according to claim 1, wherein a center line of each battery cell in the first battery cell row in the longitudinal direction and a center line of each battery cell in the second battery cell row in the longitudinal direction are not on the same line along the width direction of the battery cells.

6. 3. The battery module of claim 2, wherein the first battery cell row includes m layers of first battery cells arranged along a width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, the m layers of first battery cells and the n layers of second battery cells are arranged along a length direction of the battery cells, m and n are different, and the m layers of first battery cells and the n layers of second battery cells have the same width.

7. 3. The battery module according to claim 1, wherein the second battery cell row includes m layers of first battery cells arranged along a width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, the m layers of first battery cells and the n layers of second battery cells being arranged along a length direction of the battery cells, m and n being different, and the m layers of first battery cells and the n layers of second battery cells having the same width.

8. 8. The battery module according to claim 1, further comprising a third battery cell row adjacent to the second battery cell row along the width direction, wherein the arrangement of the battery cells in the third battery cell row is the same as the arrangement of the battery cells in the second battery cell row or the first battery cell row.

9. 8. The battery module according to claim 1, wherein the battery module includes a plurality of first battery cell rows and second battery cell rows that are alternately arranged along a width direction of the battery cells.

10. The battery module according to claim 8 , wherein the battery module includes a plurality of first battery cell rows, second battery cell rows, and third battery cell rows that are alternately arranged along a width direction of the battery cells.

11. 3. The battery module according to claim 1, wherein a length of the first battery cell is longer than a length of the second battery cell, and a center line of the first battery cell in the first battery cell row in the length direction along the width direction of the battery cells is substantially opposite to one sidewall of one of the second battery cells in the second battery cell row.

12. The battery module according to claim 1 , wherein a positive electrode active material of the first battery cell is different from a positive electrode active material of the second battery cell.

13. 13. The battery module according to claim 1, comprising two end plates arranged along a width direction, each end plate including a first surface closer to a battery cell and a second surface farther from the battery cell, and each second surface including a middle portion and two inclined portions arranged along a vertical direction, the inclined portions being arranged on both sides of the middle portion and inclined in a direction from the middle portion toward the first surface.

14. The battery module according to claim 13 , wherein the end plate further includes two stopper portions, each stopper portion being disposed on a side of the inclined portion farther from the middle portion.

15. 15. The battery module according to claim 13, further comprising a tie belt installed on an outer periphery of the battery module, one side of the tie belt being connected to an upper inclined portion of one end plate and the other side being connected to a lower inclined portion of another end plate.

16. The battery module according to claim 15 , wherein the number of the bundling belts is two, and the two bundling belts are installed crosswise.

17. The battery module according to any one of claims 1 to 16, further comprising a buffer material disposed between adjacent first and second battery cell rows.

18. 18. The battery module of claim 17, comprising a buffer material including an outer frame and one or more support ribs, the one or more support ribs being disposed inside the outer frame, a hollow structure being formed between the support rib and the outer frame, and the hollow structure facing a surface of one battery cell in the first battery cell row or the second battery cell row that has the largest area.

19. The battery module according to claim 18 , wherein the support rib abuts against an edge along the length direction of at least one battery cell in the two adjacent rows of battery cells.

20. A battery pack comprising a frame and at least one battery module row according to any one of claims 1 to 19, wherein the at least one battery module row is housed within the frame, and each battery module row includes a plurality of battery modules arranged along a width direction of the battery cells.

21. 21. The battery pack according to claim 20, comprising at least two rows of the battery modules, wherein a side member is provided between two adjacent rows of the battery modules.

22. 22. The battery pack according to claim 20, further comprising a cooling structure, the cooling structure including a cooling flow path extending in a circuitous manner along the width direction of the battery cells and used for flowing a cooling fluid.

23. 23 . The battery pack according to claim 22 , wherein a cross-sectional area of ​​the cooling flow passage in a middle portion of the battery module along a width direction of the battery cell is larger than a cross-sectional area of ​​the cooling flow passage in other portions of the battery module.

24. A power consuming device comprising the battery pack of any one of claims 20 to 23 used to supply electrical energy.

25. providing a plurality of battery cells, some of the battery cells having a different length compared to the remaining battery cells; the plurality of battery cells are arranged in at least two battery cell rows along a width direction of the battery cells, the at least two battery cell rows including a first battery cell row and a second battery cell row adjacent to each other; a step of arranging the battery cells such that a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along a width direction of the battery cells; providing the at least two battery cell strings arranged in a stacked configuration in multiple sets; the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the first battery cell row is configured by arranging first battery cells and second battery cells in a first arrangement order along a length direction, and the second battery cell row is configured by arranging first battery cells and second battery cells in a second arrangement order along a length direction, the first arrangement order and the second arrangement order being different; A method for manufacturing a battery module.

26. A method comprising the steps of providing a plurality of battery cells, some of the plurality of battery cells having different lengths compared to the remaining battery cells; the plurality of battery cells are arranged in at least two battery cell rows along a width direction of the battery cells, the at least two battery cell rows including a first battery cell row and a second battery cell row adjacent to each other; a step of arranging the battery cells such that a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along a width direction of the battery cells; providing the at least two battery cell strings arranged in a stacked configuration in multiple sets; the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the first battery cell row is configured by arranging first battery cells and second battery cells in a first arrangement order along a length direction, and the second battery cell row is configured by arranging first battery cells and second battery cells in a second arrangement order along a length direction, the first arrangement order and the second arrangement order being different; A method for manufacturing a battery module.

27. ​​A method comprising the steps of providing a plurality of battery cells, some of the plurality of battery cells having different lengths compared to the remaining battery cells; the plurality of battery cells are arranged in at least two battery cell rows along a width direction of the battery cells, the at least two battery cell rows including a first battery cell row and a second battery cell row adjacent to each other; a step of arranging the battery cells such that a center line in the length direction of at least one battery cell in the first battery cell row and a center line in the length direction of at least one battery cell in the second battery cell row are not on the same line along a width direction of the battery cells; providing the at least two battery cell strings arranged in a stacked configuration in multiple sets; the plurality of battery cells include first and second battery cells, the first and second battery cells having different lengths; the plurality of battery cells further includes third battery cells having a length different from that of the first battery cells and the second battery cells, the first battery cell row is configured by arranging the third battery cells along a length direction, the second battery cell row includes m layers of first battery cells arranged along a width direction of the battery cells and n layers of second battery cells arranged along the width direction of the battery cells, the m layers of first battery cells and the n layers of second battery cells are arranged along the length direction of the battery cells, m and n are different, and the m layers of first battery cells and the n layers of second battery cells have the same width; A method for manufacturing a battery module.

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