Patent Application
20240162544
The present application relates to the field of batteries, and in particular to a battery module, a battery pack, an electrical apparatus, and a manufacturing method for a battery module.
Energy saving and emission reduction is the key to the sustainable development of automobile industry, and electric vehicles have become an important part of the sustainable development of automobiles due to their advantages of energy saving and environmental protection. For electric vehicles, battery technology is an important factor related to their development.
For battery technology, there is always a need to improve the energy density of the battery pack, enhance the structural strength of the battery pack, improve the temperature uniformity of the battery pack, and improve the heat dissipation capacity of the battery pack.
In view of the above problems, the present application provides a battery module, a battery pack and an electrical apparatus, which can realize at least one of improving the energy density of the battery pack, enhancing the structural strength of the battery pack, improving the temperature uniformity of the battery pack, and improving the heat dissipation capacity of the battery pack.
In a first aspect, the present application provides a battery module. The battery module includes at least two rows of battery cells stacked together along the width direction of the battery cells, the at least two rows of battery cells comprising a first row of battery cells and a second row of battery cells that are adjacent to each other; the first row of battery cells and the second row of battery cells include a plurality of battery cells in total, wherein some of the battery cells in the plurality of battery cells have different lengths from the remaining battery cells, and wherein, along the width direction of the battery cells, a centerline along the length direction of at least one battery cell in the first row of battery cells is not collinear with a centerline along the length direction of at least one battery cell in the second row of battery cells.
Through a staggered structure of the battery cells with different lengths in the present application, the structural rigidity of the battery pack can be enhanced. In addition, since the centers of surfaces with the largest area of the battery cells in the adjacent rows are offset from each other along the width direction of the battery cells, the accumulated expansion degree of the centers of the surfaces with the largest area of the multiple rows of battery cells along the width direction of the battery cells is reduced, the overall expansion degree of the battery module is effectively controlled; after the battery module is mounted in the battery pack, the probability of severe extrusion deformation or even fracture two side structures of the battery pack located in the width direction of the battery cells due to the overall expansion of the battery module is reduced, thereby reducing the strength requirements for the two side structures of the battery pack and further reducing the overall weight of the battery pack.
In some embodiments, the first row of battery cells and the second row of battery cells have the same overall length, and the edge along the length direction of the first row of battery cells is flush with the edge along the length direction of the second row of battery cells. The adjacent rows of battery cells have the same length and the edges thereof in the length direction are flush, so that the battery module can be formed into a regular shape such as a solid, the space utilization rate can be maximized, and the energy density can be improved.
In some embodiments, along the width direction of the battery cells, the centerline along the length direction of each battery cell in the first row of battery cells is not collinear with the centerline along the length direction of each battery cell in the second row of battery cells. The effect of the staggered structure can be further improved by configuring each battery cell in the adjacent rows of battery cells so that the centerlines are not collinear along the width direction of the battery cells.
In some embodiments, the plurality of battery cells includes first battery cells and second battery cells, and the first battery cells and the second battery cells have different lengths. The battery cells with longer lengths can provide greater rigidity, and the battery cells with shorter lengths can provide better heat dissipation. Through the cooperation of the battery cells with different lengths, a better balance and optimization can be achieved between the overall rigidity and heat dissipation capacity of the battery module.
In some embodiments, the first row of battery cells is composed of the first battery cells arranged along the length direction, and the second row of battery cells is composed of the second battery cells arranged along the length direction. This provides an option for the selection and arrangement of the battery cells in the battery module. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the first row of battery cells is composed of the first battery cells arranged along the length direction, and the second row of battery cells is composed of the first battery cells and the second battery cells arranged along the length direction. This provides another option for the selection and arrangement of the battery cells in the battery module. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the first row of battery cells is composed of the first battery cells and the second battery cells arranged in a first order along the length direction, the second row of battery cells is composed of the first battery cells and the second battery cells arranged in a second order along the length direction, and the first order is different from the second order. This provides another option for the selection and arrangement of the battery cells in the battery module. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the first row of battery cells 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, 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 is different from n, and the m layers of first battery cells and the n layers of second battery cells have the same width. This allows batteries with different widths to be arranged in the same row, providing another option for the selection of battery cells in the battery module and the selection of the arrangement. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the second row of battery cells 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, 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 is different from n, and the m layers of first battery cells and the n layers of second battery cells have the same width. This allows batteries with different widths to be arranged in the same row, providing another option for the selection of battery cells in the battery module and the selection of the arrangement. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the plurality of battery cells further include third battery cells of which the length is different from the lengths of both the first battery cells and the second battery cells, the first row of battery cells is composed of the third battery cells arranged along the length direction, the second row of battery cells 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, 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 is different from n, and the m layers of first battery cells and the n layers of second battery cells have the same width. This provides another option for the selection and arrangement of the battery cells in the battery module. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, the battery module further includes a third row of battery cells adjacent to the second row of battery cells along the width direction, and the arrangement of the battery cells in the third row of battery cells is the same as that of the battery cells in the second row of battery cells or the first row of battery cells. This provides another option for the selection and arrangement of the battery cells in the battery module. Appropriate selection can be made according to the size requirements and energy density requirements of the battery module.
In some embodiments, along the width direction of the battery cells, the battery module includes multiple first rows of battery cells and second rows of battery cells arranged alternately. By arranging multiple rows of battery cells, the effect of the staggered structure can be further improved, and the energy of the battery pack can be increased.
In some embodiments, along the width direction of the battery cells, the battery module includes multiple first rows of battery cells, second rows of battery cells and third rows of battery cells arranged alternately. By arranging multiple rows of battery cells, the effect of the staggered structure can be further improved, and the energy of the battery pack can be increased.
In some embodiments, the length of the first battery cells is greater than the length of the second battery cells, and along the width direction of the battery cells, the centerline along the length direction of the first battery cells in the first row of battery cells is substantially opposite to a side wall of one of the second battery cells in the second row of battery cells. Since expansion is mostly severe at the centerline along the length direction of the battery cell, while expansion is relatively light at side walls, by arranging the portion with the most severe expansion opposite to the portion with relatively light expansion, the accumulation of expansion of the adjacent rows of battery cells in the battery pack along the width direction of the battery cells can be further alleviated.
In some embodiments, the positive electrode active material of the first battery cells is different from that of the second battery cells. This can provide a variety of options for the battery cells in the battery pack, such as selecting the appropriate battery cells according to energy density requirements.
In some embodiments, the battery module includes two end plates disposed along the width direction, the end plate includes a first surface close to the battery cells and a second surface away from the battery cells, and along a vertical direction, the second surface includes a middle portion and two inclined portions disposed on two sides of the middle portion and inclined from the middle portion towards the first surface. By arranging the end plates and forming the end plates to be thicker in the middle, the inclined portions are thinner than the middle portion, so that the middle portion of the end plate can withstand a greater expansion force at the centers of the surfaces with the largest area of the battery cells, while the inclined portions on two sides are more conducive to binding the rows of battery cells in cooperation with a strap.
In some embodiments, the end plate further includes two stopper portions, and each stopper portion is disposed on the side of the inclined portion away from the middle portion. By arranging the stopper portions, it is possible to prevent the strap from slipping off the end plate.
In some embodiments, the battery module further includes a strap disposed on the periphery of the battery module, one end of the strap is connected to the inclined portion on the upper side of one end plate, and the other end is connected to the inclined portion on the lower side of the other end plate. By arranging the strap and through the cooperation of the strap and the end plates, the rows of battery cells can be bound in a way of saving overall mass, and the inclined binding of the strap also enables a binding force to be distributed in the overall thickness direction of the battery module, making the binding force more uniform and firm.
In some embodiments, there are two straps disposed crosswise. Through the straps disposed crosswise, it can be ensured that the battery module is subjected to the same expansion force on the upper and lower sides, and possible local uneven stress can be avoided.
In some embodiments, the battery module includes a buffer, and the buffer is disposed between two adjacent rows of battery cells. By arranging the buffer, it is possible to effectively alleviate the accumulation of the expansion degree of the battery cells in the battery pack along the width direction of the battery cells, and avoid causing large tension to a packaging structure of the battery pack (such as the end plates of the battery module or a box of the battery pack).
In some embodiments, the battery module includes a buffer having an outer frame and one or more support ribs disposed inside the outer frame, and a hollow structure is formed between the support ribs and the outer frame, and is opposite to the surface with the largest area of one battery cell in the first row of battery cells or the second row of battery cells. By arranging the support rib, the structural rigidity of the buffer can be improved, and the hollow structure can also provide a buffer space for the expansion of the surface with the largest area in the battery module.
In some embodiments, the support ribs abut against an edge along the length direction of at least one battery cell in the two adjacent rows of battery cells. By arranging the support ribs to abut against the edge along the length direction of the battery cell, when the battery cell expands, the center of the surface with the largest area can be prevented from abutting against the edge of the battery cell in the adjacent row, avoiding possible damage to the surface with the largest area, and further improving the safety of the battery pack.
In a second aspect, the present application also provides a battery pack, including a frame and at least one column of battery modules as described above, the at least one column of battery modules being accommodated in the frame, and each column of battery modules includes a plurality of battery modules arranged along the width direction of battery cells.
In some embodiments, the battery pack includes at least two columns of battery modules, and a longitudinal beam is provided between the two adjacent columns of battery modules.
The advantages of the battery pack are similar to those of the battery module mentioned above, and will not be repeated here.
In some embodiments, the battery pack further includes a cooling structure, the cooling structure includes a cooling channel meandering along the width direction of the battery cells, and the cooling channel is configured for the flowing of cooling fluid. By arranging the cooling channel meandering along the width direction of the battery cells, the contact area between the cooling channel and the battery cells can be increased, and the cooling effect can be further improved.
In some embodiments, along the width direction of the battery cells, the cross-sectional area of the cooling channel in the middle portion of the battery module is greater than the cross-sectional area of the cooling channel in the rest of the battery module. By setting the cross-sectional area of the cooling channel to be variable, the cooling effect in the middle portion of the battery pack can be enhanced, and the overall temperature of the battery pack can be more uniform.
In a third aspect, the present application also provides an electrical apparatus, wherein the electrical apparatus includes the battery pack as mentioned above, the battery pack being configured to provide electric energy.
The advantages of the electrical apparatus are similar to those of the battery module mentioned above, and will not be repeated here.
In a fourth aspect, the present application further provides a manufacturing method for a battery module, the manufacturing method including:
The advantages of the manufacturing method for the battery module are similar to those of the battery module mentioned above, and will not be repeated here.
The above description is only a summary of the technical solutions of the present application. In order to be able to understand the technical means of the present application more clearly, the technical means can be implemented according to the content of the specification. Furthermore, to make the above and other objectives, features and advantages of the present application more comprehensible, specific implementations of the present application are exemplified below.
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of some embodiments. The drawings are for the purpose of illustrating some embodiments only and are not to be considered a limitation to the present application. Also, the same components are denoted by the same reference numerals throughout the drawings. In the drawings:
Reference numerals in Detailed Description are as follows:
Examples of the technical solutions of the present application will be described in detail below in conjunction with the drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and therefore are only used as examples and cannot be used to limit the scope of protection of the present application.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art belonging to the technical field of the present application; the terms used herein are intended only for the purpose of describing specific examples and are not intended to limit the present application; the terms “including” and “having” and any variations thereof in the specification and the claims of the present application and in the description of drawings above are intended to cover non-exclusive inclusion.
In the description of the embodiments of the present application, the technical terms “first”, “second”, and the like are used only to distinguish between different objects, and are not to be understood as indicating or implying a relative importance or implicitly specifying the number, particular order, or primary and secondary relation of the technical features indicated. In the description of the embodiments of the present application, the meaning of “a plurality of” is two or more, unless otherwise explicitly and specifically defined.
Reference herein to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
In the description of the embodiments of the present application, the term “and/or” is only an association relationship for describing associated objects, indicating that there may be three relationships, for example A and/or B may represent three situations: A exists alone, both A and B exist, and B exists alone. In addition, the character “/” herein generally means that front and rear associated objects are in an “or” relationship. In this disclosure, the phrases “at least one of A, B, and C” and “at least one of A, B, or C” both mean only A, only B, only C, or any combination of A, B, and C.
In the description of the embodiments of the present application, the term “a plurality of” refers to two or more (including two), and similarly, “multiple groups” refers to two or more (including two) groups, and “multiple sheets” refers to two or more (including two) sheets.
In the description of the embodiments of the present application, the orientation or position relationship indicated by the technical terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “upper,” “lower,” “front,” “back,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial”, “radial”, “circumferential”, etc. are based on the orientation or position relationship shown in the drawings and are intended to facilitate the description of the embodiments of the present application and simplify the description only, rather than indicating or implying that the device or element referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore are not to be interpreted as limitations on the embodiments of the present application.
In the description of the embodiments of the present application, unless otherwise expressly specified and limited, the technical terms “mount,” “join,” “connect,” “fix,” etc. should be understood in a broad sense, such as, a fixed connection, a detachable connection, or an integral connection; a mechanical connection, or an electrical connection; a direct connection, an indirect connection through an intermediate medium, an internal connection of two elements, or interaction between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations.
At present, from the perspective of the development of the market situation, power batteries are more and more widely used. The power batteries are used in energy storage power source systems such as hydraulic, thermal, wind and solar power stations as well as in electric vehicles such as electric bicycles, electric motorcycles and electric cars, and military equipment and aerospace fields. With the continuous expansion of the application field of the power batteries, the market demand is also constantly expanding.
The inventors have noticed that as ions are embedded into or released from positive electrode active material and negative electrode active material during a charge-discharge cycle of a battery cell, the battery cell will expand due to the side reaction accumulation thickness of a battery cell system and the peeling off of graphite sheets, the expansion of the battery cell usually occurs in the surface with the largest area of the battery cell, and the expansion degree is more severe at a centerline along the length direction of the surface with the largest area, but less at edges of the surface with the largest area. The battery pack is usually provided with multiple rows of battery cells, and expansion of the multiple rows of battery cells may be accumulated with each other, resulting in severe extrusion, deformation or even fracture of the battery cells and packaging structures on two sides of the battery pack, which is not only unfavorable to the safety of the battery pack itself, but may also lead to an increase in the overall weight of the battery pack and a decrease in the energy density of the battery pack if the packaging structures on two sides are strengthened. The packaging structure of the battery pack may include end plates on two sides of the battery module or a box structure of the battery pack.
In addition, the battery cells may generate heat during the charge-discharge cycle, and generally longer battery cells have worse heat dissipation capacity. For the battery cell, the portion near the edges of the battery cell has faster heat dissipation and lower temperature, and the position near the middle of the battery cell has poor heat dissipation and high temperature, which may make polarization of the same battery cell at the low temperature portions on two sides greater than that at the high temperature portion in the middle, make the same battery cell has different charge-discharge capacity at different positions, easily leading to lithium plating from electrode plates at the low temperature portions and thus leading to safety accidents.
In addition, since the battery pack needs to have sufficient rigidity to avoid damage or breakage when in use, the battery pack is usually provided with various reinforcement structures therein, such as various cross beams and longitudinal beams. Although the reinforcement structures can improve the overall rigidity of the battery pack, the arrangement of the reinforcement structures will also occupy the space in the battery pack and reduce the energy density of the battery pack.
Therefore, improving the energy density of the battery pack, enhancing the structural strength of the battery pack, improving the temperature uniformity of the battery pack, and improving the heat dissipation capacity of the battery pack have always been research directions in the field of batteries. The overall performance of the battery pack can be improved by any one of improving the energy density of the battery pack, enhancing the structural strength of the battery pack, improving the temperature uniformity of the battery pack, or improving the heat dissipation capacity of the battery pack.
To further improved the overall performance of the battery pack, the inventors designed a battery module of a battery pack through in-depth research. The battery module includes at least two rows of battery cells stacked together along the width direction of the battery cells, the at least two rows of battery cells comprising a first row of battery cells and a second row of battery cells that are adjacent to each other; the first row of battery cells and the second row of battery cells include a plurality of battery cells in total, wherein some of the battery cells in the plurality of battery cells have different lengths from the remaining battery cells, and wherein, along the width direction of the battery cells, a centerline along the length direction of at least one battery cell in the first row of battery cells is not collinear with a centerline along the length direction of at least one battery cell in the second row of battery cells.
In the new battery module proposed by the inventors, a staggered structure is formed by the non-collinear centerlines of the battery cells in the adjacent rows of battery cells, and the rigidity of the battery module is enhanced by the staggered structure itself, so that the use of reinforcement structures in the battery pack can be reduced. In addition, due to the staggered structure, centerlines along the length direction of the surfaces with the largest area of the battery cells in the adjacent rows are not collinear, which reduces the accumulation of the expansion degree of the battery cells, and thus reduce the extrusion to the packaging structures on two sides of the battery pack.
In addition, the use of batteries with different lengths allows for more convenient use of batteries with different chemical systems, and the batteries with different chemical systems have different energy densities, so that the energy density can be adjusted more conveniently by selecting the number and arrangement of the batteries with different lengths.
Moreover, by properly selecting the lengths of the batteries, the battery module with a staggered structure can be formed into a regular structure, such as a conventional square structure, which can maximize the space utilization rate and improve the energy density in a limited space.
The battery cell disclosed in the embodiments of the present application can be used, but not limited to, in electrical apparatuses such as a vehicle, a ship, or an aircraft. A power supply system of the electrical apparatus may be composed of the battery cells and batteries disclosed in the present application.
Embodiments of the present application provide an electrical apparatus that uses a battery as a power supply, and the electrical apparatus may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery vehicle, an electric vehicle, a ship, a spacecraft, and so on. The electric toy may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, and the like. The spacecraft may include airplanes, rockets, space shuttles, spaceships, and the like.
For the convenience of description, the following embodiments are illustrated with an example in which the electrical apparatus according to an embodiment of the present application is a vehicle 1000.
Please refer to
In some embodiments of the present application, the battery 100 not only may serve as an operating power source of the vehicle 1000, but also may serve as a driving power source of the vehicle 1000, thus replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.
Please referring to
The lower box 20 and the upper end cover 50 are configured to provide an accommodating space for the battery module 10 when closed together. The lower box body 20 may be a hollow structure with one end open, the upper end cover 50 may be a plate-shaped structure, and the upper end cover 50 covers the open end of the lower box 20, so that the lower box 20 and the upper end cover 50 jointly define the accommodating space. For example, both the lower box 20 and the upper end cover 50 may be a hollow structure with one end open, and the open end of the lower box 20 covers the opening end of the lower end cover 50. Certainly, a box body formed by the lower box 20 and the upper end cover 50 can be of various shapes, such as a cylinder or a cuboid.
The battery module 10 includes a plurality of battery cells. There may be a plurality of battery cells, and the plurality of battery cells 20 can be connected in series, in parallel or in a mixed connection, wherein the mixed connection means that the plurality of battery cells are connected in both series and parallel. The plurality of battery cells can be directly connected in series, in parallel or in a mixed connection, and then a whole body composed of the plurality of battery cells is accommodated into the lower box 20. Certainly, the plurality of battery cells may be first connected in series, in parallel or in a mixed connection to form a battery module 10, and the plurality of battery modules are further connected in series, in parallel or in a mixed connection to form a whole, and accommodated in the lower box 20. The battery pack 1 may further include other structures, for example, the battery pack 1 may further include a bus member configured to achieve electrical connection of the plurality of battery cells.
Each battery cell may be a secondary battery or a primary battery; or may be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cells may be flat, rectangular, or in other shapes.
The power management module 30 may be arranged in the lower box 20, for example, arranged in the front end portion of the lower box 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, state of charge monitoring, and can obtain voltage, current, temperature, state of charge and so on as thermal runaway detection data.
The cooling structure 40 is arranged under the lower box 20, and a cooling channel is disposed in the cooling structure 40, and cooling liquid may circulate in the cooling channel for cooling the battery pack 1.
The box protection bottom plate 60 is arranged under the cooling structure 40 for protecting the lower box 20 and preventing the battery pack 1 from being damaged, for example, by an impact from below. The box protection bottom plate, the lower box body and the upper end cover may be formed of copper, iron, aluminum, stainless steel, aluminum alloy, or the like, which are not particularly limited in the present application.
In addition, as shown in
According to some embodiments of the present application, referring to
The battery cell is of a square case structure with six surfaces. The “width direction” is the x direction in
As shown in
In addition, by arranging the center of the surface with the largest area of at least one battery cell 11 to be offset from the center of the surface with the largest area of at least one battery cell 12, an effective staggered structure can be formed, and the staggered structure itself can provide enhanced rigidity for the battery module 10, which is beneficial to reducing the need for the use of cross beams in the battery pack. Comparing
Some of the battery cells shown in the first to tenth embodiments of the battery module 10 are elongated cuboid batteries, some of the battery cells are ordinary cuboid batteries, and some of the battery cells are cubic batteries.
The differences between the first to tenth embodiments of the battery module 10 mainly are the different sizes of the battery cells and the different combinations and arrangements of the battery cells in adjacent rows included in each embodiment. In addition to this, the other structures of the first to tenth embodiments of the battery module 10 are basically the same, and the repeated parts between the different embodiments will not be repeated below. For example, in the first embodiment of the battery module 10 in
Returning to
“The edge along the length direction of the battery cells” refers to the side edge of the adjacent rows of battery cells extending along the x direction. “Flush with” means that the edges along the length direction of the adjacent rows of battery cells are collinear along the x-direction.
The adjacent rows of battery cells have the same length and the edges along the length direction thereof are flush, so that the battery module can be 10 may be formed into a solid, such a cuboid or a cube. Generally, a battery pack frame of the battery pack 1 and an accommodating space enclosed by the battery pack frame and longitudinal beams for accommodating the battery module 10 are solid in shape, so as to reduce the processing cost of the battery pack, maximize the space, and facilitate the installation of the battery pack. Therefore, in this case, the battery module 10 formed into the solid can further improve the utilization rate of the accommodating space of the battery pack 1, thereby further increasing the battery density.
The second to tenth embodiments of the battery module 10 shown in
Returning to
By arranging each battery cell in the adjacent rows of battery cells to be not collinear, a firmer 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 rows of battery cells can be further relieved.
In the second embodiment to tenth embodiment of the battery module 10 shown in
In addition, in the first embodiment to the tenth embodiment of the battery module 10 shown in
Generally, the longer the length of battery cells, the worse the heat dissipation effect, but the stronger the structural rigidity. Through mutual cooperation of the battery cells with different lengths, acceptable or good heat dissipation effect can be achieved while ensuring the structural rigidity, and a good balance and improvement can be achieved between the structural rigidity and overall heat dissipation of the battery pack.
Returning to
In
In the different embodiments shown in
Referring to
Therefore, this provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10, and can still achieve the advantages that the above staggered structure enhances the structural strength, and the centers of the surfaces with the largest area are offset so that the accumulation of expanded battery cells in the battery pack is relieved, and the space utilization rate and the battery energy density are improved.
Referring to
Similarly, in the fifth embodiment of the battery module 10 shown in
Therefore, this also provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10.
Referring to
Therefore, this also provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10.
Referring to
Furthermore, this also provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10.
Referring to
Furthermore, this also provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10.
Referring to
The seventh to tenth embodiments of the battery module 10 shown in
The ninth embodiment of the battery module 10 shown in
That is, the battery module in the present application may further include one or more additional rows of battery cells in addition to the first rows of battery cells and the second rows of battery cells, and the one or more rows of battery cells may be adjacent to the first row of battery cells or the second row of battery cells, and the arrangement of the battery cells in the one or more rows of battery cells may be the same as that of the battery cells in the first row of battery cells or the second row of battery cells.
Furthermore, this also provides an optional alternative for the selection and arrangement of different battery cells in the battery module 10.
Returning to
The different embodiments of the battery module 10 shown in
By alternately arranging the multiple rows of battery cells, the staggered effect can be further enhanced, and the battery energy can be further improved.
Returning to
In the present application, the use of battery cells with different lengths allows for more convenient use of battery cells with different chemical systems. For example, in the above embodiments, the positive electrode active material of the first battery cell 11, the second battery cell 12 and/or the third battery cell 13 may be different.
In some embodiments, the positive electrode active material may be a positive electrode active material for batteries well known in the art. The positive electrode material may be, for example, 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 and Prussian blue compounds, etc. For example, the positive electrode active material may include at least one of a lithium-containing phosphate of 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 useful as positive electrode active materials for batteries can also be used. These positive electrode active materials may be used alone or in combination of two or more. Here, examples of the lithium transition metal oxide may include, but are not limited to, at least one of a lithium-cobalt oxide (such as LiCoO2), lithium-nickel oxide (such as LiNiO2), lithium-manganese oxide (such as LiMnO2 and LiMn2O4), lithium-nickel-cobalt oxide, lithium-manganese-cobalt oxide, lithium-nickel-manganese oxide, lithium-nickel-cobalt-manganese oxide (such as LiNi1/3Co1/3Mn1/3O2 (also abbreviated as NCM333), LiNi0.5Co0.2Mn0.3O2 (also abbreviated as NCM523), LiNi0.5Co0.25Mn0.25O2 (also abbreviated as NCM211), LiNi0.6Co0.2Mn0.2O2 (also abbreviated as NCM622), LiNi0.5Co0.1Mn0.1O2 (also abbreviated as NCM811)), lithium-nickel-cobalt-aluminum oxide (such as LiNi0.85Co0.15Al0.05O2) and their respective modified compounds. Examples of the lithium-containing phosphate with olivine structure may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also abbreviated as LFP)), lithium iron phosphate-carbon composite, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate-carbon composite, lithium iron manganese phosphate, and lithium iron manganese phosphate-carbon composite.
In addition, the battery cells with different lengths may be battery cells with different energy densities. For example, some battery cells are batteries with low energy density/gram capacity, such as sodium-ion batteries, lithium iron phosphate batteries, and lithium manganate batteries, while the other battery cells are batteries with high energy density/gram capacity, such as ternary NCM or NCA batteries, lithium metal batteries, etc. By using the battery cells with different chemical systems, the energy density of the battery module can be more conveniently custom designed.
The first battery cells 11, the second battery cells 12 and/or the third battery cells 13 use different positive electrode active materials, for example, one or two kinds of the battery cells are ternary batteries, and the other or two kinds are lithium iron phosphate batteries, so that the cost of the entire battery module and accordingly the cost of the entire battery pack is reduced by using the lithium iron phosphate batteries, and the safety of the battery pack is improved due to the characteristic of resistance to thermal runaway, for example, in a case of thermal runaway of the ternary batteries, the lithium iron phosphate batteries can be used as a barrier to maintain the safety of the entire battery module and battery pack. Meanwhile, the use of the ternary batteries ensures the good performance of the battery module and the battery pack. In addition, the different curve characteristics of the ternary batteries and lithium iron phosphate batteries can also be used to improve the measurement accuracy of the state of charge of the battery pack.
Referring to
Therefore, the end plate 14 has a configuration that is thick in the middle and thin on two sides. The middle portion has higher structural strength, so that the deformation of the end plate caused by the expansion of the surface with the largest area in the battery can be resisted. Due to the arrangement of the inclined portions on two sides, binding can be more conveniently performed, and furthermore, the crosswise binding of the strap can be facilitated when the paired end plates are assembled with the plurality of battery cells.
In
By arranging the stopper portions 144, the strap can be prevented from slipping off the end plates 14, when the strap is used for binding.
Referring to
The strap is usually a steel strap or a polymer nylon bag, which is light in weight. Therefore, by using the strap to assemble the battery module 10, the weight of the assembled battery module can be further reduced. In addition, through the oblique binding method of the strap, a binding force can be applied to the battery module 10 in the entire range from the inclined portion on the upper side to the inclined portion on the lower side, so that the battery module 10 is more uniformly stressed and bound more firmly.
In addition, two straps 15 are shown in
Moreover, through the mutual cooperation of the straps and the end plates, the overall structural rigidity of the battery pack can be further enhanced, and the need for reinforcement members in the battery pack can be further reduced.
By arranging the supporting rib, the structural rigidity of the buffer can be improved, so as to prevent the middle portion of the frame from bending downward by gravity due to, for example, the buffer being too thin.
The second embodiment of the buffer 16 in
In the present application, due to the staggered arrangement of the battery cells with different lengths, the centers of the surfaces with the largest area of the battery cells in the adjacent rows are offset from each other, and the center of the surface with the largest area of the battery cell in one row of battery cells abuts against the edge of the battery cell in the adjacent row. However, the edge of the battery cell forms a corner. When the center of the surface with the largest area expands to abut against the corner, the center of the surface with the largest area may be stressed too much, and the center of the surface with the largest area may be damaged with repeated charge and discharge and the accumulation of the expansion degree. By arranging the position of the support rib to correspond to the edge of the battery cell, the risk of damage to the surface with the largest area of the battery cell can be reduced.
According to some embodiments of the present application, the present application further provides a battery pack 1, the battery pack 1 including a lower box 20 and any embodiment of the battery module 10 mentioned above. Referring to
In addition, as shown in
The cooling structure 40 may be formed into a plate shape. The cooling structure 40 may be made of metal with excellent thermal conductivity, such as copper, iron, aluminum, stainless steel, aluminum alloy, and so on, which is not particularly limited in the present application.
In some embodiments, the cross-sectional area of the cooling channel 400 varies, and the cross-sectional area of the cooling channel 400 in the middle portion of the battery module 10 is greater than that in the rest of the battery module 10 along the width direction of the battery cells. By designing the cross-sectional area of the cooling channel 400 in the middle portion to be larger, heat dissipation in the middle portion of the battery pack can be enhanced. Since the temperature distribution of the battery pack is higher at the center than at the edges, the uneven temperature may lead to amplified differences in the charge and discharge performance of the different battery cells, and may lead to safety accidents such as lithium plating. By setting the cross-sectional area of the cooling channel in the present application, the temperature of the battery pack can be more uniform.
According to some embodiments of the present application, the present application further provides an electrical apparatus, including any embodiment of the battery pack mentioned above, the battery pack being configured to provide electric energy.
The electrical apparatus may be any of the aforementioned apparatuses or systems in which the battery is applied.
According to some embodiments of the present application, the present application further provides a manufacturing method for a battery module, the manufacturing method including:
Finally, it should be noted that the above embodiments are merely used for illustrating rather than limiting the technical solutions of the present application. Although the present application has been described in detail with reference to the above various embodiments, those of ordinary skill in the art should understand that the technical solutions specified in the above various embodiments can still be modified, or some or all of the technical features therein can be equivalently substituted; and such modifications or substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the various embodiments of the present application, which shall fall within the scope of the claims and the specification of the present application. In particular, the technical features mentioned in the various examples can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but rather includes all technical solutions falling within the scope of the claims.
This application is a continuation of International Application No. PCT/CN2021/134552, filed on Nov. 30, 2021, the entire content of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2021/134552 | Nov 2021 | US |
| Child | 18423607 | US |
