Battery device and electric equipment

Abstract

The utility model discloses a battery device and electric equipment, the battery device comprises a box body and a battery assembly, the battery assembly is arranged in the box body, the battery assembly comprises a shell, a soft package battery cell and a heating element, and the shell forms an accommodating space and is connected with the box body; the soft package battery cell is arranged in the accommodating space and is bonded with the box body; the heating element is in heat conduction connection with the soft package battery cell and is used for heating the soft package battery cell. In the battery device, the shell can provide mechanical protection outside the plurality of soft package battery cells, so that the risk that the soft package battery cells are damaged due to external mechanical impact is reduced, and the positions of the plurality of soft package battery cells can be better fixed; furthermore, the heating element can heat the soft package battery cell, so that the temperature of the soft package battery cell can be in a proper temperature range under the condition that the environment temperature is relatively low, and the performance reliability of the soft package battery cell can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery device and an electrical equipment. Background Art

[0002] In the related art, batteries are widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in multiple fields such as military equipment and aerospace. According to the hardness of the outer shell, batteries can be roughly classified into soft-pack batteries and hard-shell batteries. Soft-pack batteries have the advantages of relatively large mass / volume energy density and good safety, making the application of soft-pack batteries more and more extensive. When soft-pack batteries work at relatively low temperatures, their performance will be affected. Thus, how to improve the performance reliability of soft-pack batteries at relatively low ambient temperatures has become a technical problem to be solved. Summary of the Utility Model

[0003] In view of the above problems, the utility model provides a battery device and an electrical equipment, and the technical problem to be solved is to improve the capacitance of soft-pack batteries at relatively low ambient temperatures.

[0004] In a first aspect, the utility model provides a battery device, which includes a box body and a battery assembly. The battery assembly is arranged in the box body. The battery assembly includes an outer shell, a soft-pack battery cell, and a heating element. The outer shell forms a receiving space and is connected to the box body; the soft-pack battery cell is arranged in the receiving space and is bonded to the box body; the heating element is thermally connected to the soft-pack battery cell for heating the soft-pack battery cell.

[0005] In the above battery device, the outer shell can provide mechanical protection for the outside of multiple soft-pack battery cells, reducing the risk of damage to the soft-pack battery cells caused by external mechanical impacts, and can also better fix the positions of multiple soft-pack battery cells; further, the heating element can heat the soft-pack battery cells, so that the soft-pack battery cells can keep their own temperatures within a suitable temperature range at relatively low ambient temperatures, thereby improving the performance reliability of the soft-pack battery cells.

[0006] In some embodiments of the utility model, at least part of the heating element is arranged in the receiving space and is connected to the soft-pack battery cell.

[0007] In the above technical solution, the distance between the heating element and the soft-pack battery cell is closer, and the heating efficiency of the heating element for heating the soft-pack battery cell is higher.

[0008] In some embodiments of the utility model, the outer shell includes two side walls and a connecting wall. The two side walls are arranged opposite to each other, and the connecting wall connects the two side walls. The connecting wall and the two side walls jointly enclose the receiving space.

[0009] In the above technical solution, the outer shell formed by the two side walls and the connecting wall enables the soft-pack battery cell to be more easily installed into the accommodation space.

[0010] In some embodiments of the present invention, at least a part of the heating element is connected to the surface of the soft-pack battery cell facing the connecting wall.

[0011] In the above technical solution, the heating element can heat the soft-pack battery cell through the surface of the soft-pack battery cell facing the connecting wall, so that the temperature of the soft-pack battery cell itself is within a suitable temperature range.

[0012] In some embodiments of the present invention, at least a part of the heating element is connected to the surface of the soft-pack battery cell facing away from the connecting wall.

[0013] In the above technical solution, the heating element can heat the soft-pack battery cell through the surface of the soft-pack battery cell facing away from the connecting wall, so that the temperature of the soft-pack battery cell itself is within a suitable temperature range.

[0014] In some embodiments of the present invention, the heating element is connected to at least two surfaces of the soft-pack battery cell.

[0015] In the above technical solution, the area where the heating element is connected to the soft-pack battery cell is relatively large, which can improve the heating efficiency of the heating element for the soft-pack battery cell.

[0016] In some embodiments of the present invention, the soft-pack battery cell includes a first outer surface, a second outer surface, and a third outer surface. The first outer surface faces the side wall, the second outer surface faces the connecting wall, the third outer surface faces away from the second outer surface, and the heating element is connected to the first outer surface and the second outer surface, or is connected to the first outer surface and the third outer surface.

[0017] In the above technical solution, the heating element is connected to the first outer surface and the second outer surface, or is connected to the first outer surface and the third outer surface, so that the heating element can be connected to at least two surfaces of the soft-pack battery cell.

[0018] In some embodiments of the present invention, the number of the soft-pack battery cells is multiple, and the multiple soft-pack battery cells are arranged between the two side walls. The heating element forms a heating space, and the multiple soft-pack battery cells are arranged in the same heating space.

[0019] In the above technical solution, the multiple soft-pack battery cells are arranged in the same heating space, so that the heating element can surround all the soft-pack battery cells in the same battery assembly, and it is easier for the heating element to be connected to the soft-pack battery cells.

[0020] In some embodiments of the present utility model, the number of the soft-pack battery cells is multiple, and the multiple soft-pack battery cells are arranged between the two side walls. The heating element is in a winding shape and forms a plurality of heating spaces, and at least one of the soft-pack battery cells is disposed in each heating space.

[0021] In the above technical solution, at least one of the soft-pack battery cells is disposed in each heating space, so that the contact area between the soft-pack battery cell and the heating element can be increased, thereby improving the heating efficiency of the heating element for the soft-pack battery cell.

[0022] In some embodiments of the present utility model, the resistance of the heating element is X, where 5Ω < X < 80Ω.

[0023] In the above technical solution, when the resistance of the heating element is within the above range, the heating element can not only generate heat quickly, but also make the heating temperature within a predetermined range, which is beneficial to heating the soft-pack battery cell.

[0024] In some embodiments of the present utility model, the heating element is integrally in a sheet shape and has a thickness of D, where 0.2mm < D < 1.5mm.

[0025] In the above technical solution, when the thickness of the heating element is within the above range, the heating element is easy to manufacture and occupies a small space in the battery assembly, so that the soft-pack battery cell occupies a large space, and the energy density of the battery assembly can be increased.

[0026] In some embodiments of the present utility model, the normal operating temperature of the heating element is T, where 45°C ≤ T ≤ 65°C.

[0027] In the above technical solution, the operating temperature of the heating element can effectively heat the soft-pack battery cell to increase the temperature of the soft-pack battery cell itself.

[0028] In some embodiments of the present utility model, when the number of the soft-pack battery cells in the accommodation space is greater than 3, 45°C ≤ T ≤ 55°C; and / or when the number of the soft-pack battery cells in the accommodation space is less than or equal to 3, 55°C ≤ T ≤ 65°C.

[0029] In the above technical solution, when the number of the soft-pack battery cells is greater than 3, the total heat generated by the soft-pack battery cells themselves is more. Therefore, the operating temperature of the heating element at 45°C to 55°C can meet the heating requirements of the soft-pack battery cells; when the number of the soft-pack battery cells in the accommodation space is less than or equal to 3, the total heat generated by the soft-pack battery cells themselves is less, and the operating temperature of the heating element at 55°C to 65°C can meet the heating requirements of the soft-pack battery cells.

[0030] In some embodiments of the present invention, the heating element is arranged outside the accommodating space, and heats the soft-pack battery cell through the outer shell.

[0031] In the above technical solution, the heating element can heat the soft-pack battery cell through the shell, so that the temperature of the soft-pack battery cell itself can be increased.

[0032] In some embodiments of the present invention, the soft-pack battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell and a solid-state battery cell.

[0033] In the above technical solution, the use of the above types of soft-pack cells can provide more options for the design of battery devices to meet different usage requirements. Among them, the soft-pack cells are lithium iron phosphate battery cells, which have the advantages of high reliability, long cycle life, light weight, large capacity, and low internal resistance; the soft-pack cells are ternary battery cells, which have the advantages of high energy density and good electrochemical performance; the soft-pack cells are solid-state battery cells, which have the advantages of high energy density and high reliability, light weight, and good high and low temperature performance.

[0034] In some embodiments of the utility model, the soft-pack battery cell is a ternary battery cell, the shell includes two side walls and a connecting wall, the two side walls are arranged opposite to each other, the connecting wall connects the two side walls, the connecting wall and the two side walls together enclose the accommodating space, and the connecting wall is provided with a pressure relief portion.

[0035] In the above technical solution, when the ternary battery cell undergoes thermal runaway expansion and exhaust pressure relief, the pressure relief unit can guide the exhausted gas to directional pressure relief, thereby reducing the risk of gas chaos affecting the surrounding ternary battery cells, and also reducing the risk of severe thermal runaway of the battery pack composed of the ternary battery cells, which is beneficial to the thermal runaway management of the battery assembly and improves the reliability of the battery assembly composed of the ternary battery cells.

[0036] In some embodiments of the present invention, the pressure relief portion is configured as a pressure relief hole; or, the pressure relief portion is configured as a notch; or, the pressure relief portion is configured as a weakened portion.

[0037] In the above technical solution, more options can be provided for the design of the pressure relief part to meet different usage requirements.

[0038] In some embodiments of the present invention, there are multiple battery assemblies, and the multiple battery assemblies are arranged along a predetermined direction.

[0039] In the above-mentioned battery device, the plurality of battery modules can increase the capacity of the battery device.

[0040] In some embodiments of the present utility model, the heating elements of the plurality of battery assemblies are connected in series and connected to the bus of the battery device.

[0041] In the above technical solution, the plurality of heating elements are connected in series, making it easy to manage the heating elements. In addition, the heating elements are connected to the bus of the battery device, so that the soft-pack battery cells can supply power to the heating elements.

[0042] In some embodiments of the present utility model, each heating element includes two connecting wires, and the plurality of heating elements are connected in series through the connecting wires.

[0043] In the above technical solution, the connecting wires make it easier to connect the heating elements in series.

[0044] In some embodiments of the present utility model, the housing includes two side walls and a connecting wall. The two side walls are arranged opposite to each other, and the connecting wall connects the two side walls. The connecting wall and the two side walls together enclose the accommodating space. The connecting wire bypasses the edge of the side wall, or the connecting wire penetrates through the side wall.

[0045] In the above technical solution, the connecting wire bypasses the edge of the side wall, or the connecting wire penetrates through the side wall, so that the heating elements in the plurality of battery assemblies can be connected in series.

[0046] In some embodiments of the present utility model, the heating element includes a body, and the two connecting wires are connected to the corners of the body and are on different sides of the body respectively.

[0047] In the above technical solution, the position of the connecting wires makes it easier to connect the plurality of heating elements in series.

[0048] In some embodiments of the present utility model, the battery device includes a control switch connected in series between the bus and the heating element.

[0049] In the above technical solution, the control switch can control the energization or de-energization of the heating element, thereby controlling the working state of the heating element.

[0050] In some embodiments of the present utility model, the plurality of battery assemblies are connected in series and connected to the bus.

[0051] In the above battery assembly, the plurality of battery assemblies are connected in series to the bus, which can facilitate the electrical management of the battery assemblies.

[0052] In a second aspect, the present utility model provides an electrical equipment, including: the battery device according to the second aspect of the present utility model above.

[0053] In the above technical solution, the electrical device includes the above battery device, and the battery device has a high energy density, which is beneficial to improving the overall performance of the electrical device.

[0054] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present utility model. Description of the Drawings

[0055] The above and / or additional aspects and advantages of the present utility model will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0056] Figure 1 is a schematic structural diagram of a vehicle according to some embodiments of the present utility model;

[0057] Figure 2 is an exploded perspective view of a battery device according to some embodiments of the present utility model;

[0058] Figure 3 is a cross-sectional view of a battery assembly according to some embodiments of the present utility model;

[0059] Figure 4 is one of the partial cross-sectional views of a battery device according to some embodiments of the present utility model;

[0060] Figure 5 is another partial cross-sectional view of a battery device according to some embodiments of the present utility model;

[0061] Figure 6 is yet another partial cross-sectional view of a battery device according to some embodiments of the present utility model;

[0062] Figure 7 is still another partial cross-sectional view of a battery device according to some embodiments of the present utility model;

[0063] Figure 8 is a circuit schematic diagram of a battery device according to some embodiments of the present utility model;

[0064] Figure 9 is Figure 6 an enlarged view of part A in

[0065] Figure 10 is a plan view of a heating element according to some embodiments of the present utility model.

[0066] Explanation of the Reference Numerals:

[0067] 100 - Battery device; 110 - Box body; 120 - Battery assembly; 10 - Soft - pack battery cell; 11 - First outer surface; 12 - Second outer surface; 13 - Third outer surface; 20 - Outer shell; 21 - Accommodating space; 22 - Side wall; 23 - Connecting wall; 24 - Pressure - relief part; 30 - Heating element; 31 - Heating space; 32 - First heating part; 33 - Second heating part; 34 - Connecting wire; 35 - Body; 36 - Electric heating wire; 40 - Bus; 50 - Control switch; 1000 - Vehicle; 200 - Controller; 300 - Motor. Detailed implementation manners

[0068] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts belong to the scope of protection of the present utility model.

[0069] Unless otherwise defined, all technical and scientific terms used in the present utility model have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs; the terms used in the description of the present utility model in the specification of the utility model are only for the purpose of describing specific embodiments, and are not intended to limit the present utility model; the terms "including" and "having" and any variations thereof in the specification and claims of the present utility model and the above - mentioned drawings are intended to cover non - exclusive inclusion. The terms "first", "second", etc. in the specification and claims of the present utility model or the above - mentioned drawings are used to distinguish different objects, rather than to describe a specific order or primary - secondary relationship.

[0070] Referring to "embodiments" in the present utility model means that specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present utility model. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0071] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "attached" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above - mentioned terms in the present utility model can be understood according to specific situations.

[0072] In the present utility model, the term "and / or" only describes the associated relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, in the present utility model, the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0073] In the embodiments of the present utility model, the same reference numerals represent the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width, etc. of various components in the embodiments of the present utility model shown in the drawings, as well as the overall thickness, length, width, etc. of the integrated device, are only illustrative and should not constitute any limitation to the present utility model.

[0074] The term "a plurality of" as used in the present utility model refers to two or more (including two).

[0075] In the embodiments of the present utility model, if there is no special description, all the implementation manners and optional implementation manners of the present utility model can be combined with each other to form a new technical solution.

[0076] In the embodiments of the present utility model, if there is no special description, all the technical features and optional technical features of the present utility model can be combined with each other to form a new technical solution.

[0077] In the related art, batteries are widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in multiple fields such as military equipment and aerospace. Batteries can be roughly classified into soft-pack batteries and hard-shell batteries according to the hardness of the outer shell. Soft-pack batteries have the advantages of relatively large mass / volume energy density and good safety, which makes the application of soft-pack batteries more and more extensive. When soft-pack batteries work at relatively low temperatures, their use performance will be affected. Thus, how to improve the performance reliability of soft-pack batteries under relatively low ambient temperatures has become a technical problem to be solved.

[0078] For this reason, the present utility model provides a battery assembly. The battery assembly includes a housing, a soft-pack battery cell, and a heating element. The housing forms a receiving space; the soft-pack battery cell is disposed in the receiving space; the heating element is thermally connected to the soft-pack battery cell for heating the soft-pack battery cell.

[0079] In the above-mentioned battery assembly, the housing can provide mechanical protection outside multiple soft-pack battery cells, reducing the risk of damage to the soft-pack battery cells caused by external mechanical impacts; further, the heating element can heat the soft-pack battery cells, enabling the soft-pack battery cells to maintain their temperatures within a suitable temperature range under relatively low ambient temperatures, thereby improving the performance reliability of the soft-pack battery cells. For example, the capacitance of the soft-pack battery cells can be increased.

[0080] An embodiment of the present utility model further provides an electrical device using a battery device as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, and the like. Among them, the electric toy may include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric aircraft toy, and the like. The spacecraft may include an airplane, a rocket, a space shuttle, a spaceship, and the like.

[0081] For the convenience of description, the following embodiments take a vehicle 1000, which is an electrical device according to an embodiment of the present utility model, as an example for illustration.

[0082] Please refer to Figure 1 , the vehicle 1000 may be a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, an extended-range vehicle, or the like. Further, the vehicle 1000 may be a commercial vehicle. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be disposed at the bottom, the head, or the tail of the vehicle 1000. The battery device 100 may be used to supply power to the vehicle 1000. For example, the battery device 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the working power requirements during the start, navigation, and driving of the vehicle 1000.

[0083] In some embodiments of the present utility model, the battery device 100 may not only be used as an operating power source for the vehicle 1000, but also be used as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0084] Please refer to Figures 2 - 3 , in an embodiment of the present utility model, the battery device (Battery Apparatus) 100 may include one or more battery components for providing voltage and capacity. The battery cell assembly (Battery Cell Assembly) may include a plurality of pouch cells 10, and the plurality of pouch cells 10 are connected in series, parallel, or in a hybrid connection through a busbar component. For example, the battery cell assembly (Battery Cell Assembly) is usually formed by arranging a plurality of pouch cells 10; the battery cell assembly may be a battery module (Battery Module), and the battery module is formed by arranging and fixing a plurality of pouch cells 10 to form an independent module. As an example, the battery module may be formed by bundling a plurality of pouch cells 10 with a cable tie.

[0085] The battery device 100 may be a battery pack, which includes a box body 110 and one or more battery components 120. The battery components 120 are accommodated in the box body 110. The battery components 120 may be battery modules, and the battery components 120 may be accommodated in the box body 110 by fixing the battery modules in the box body 110; the battery components 120 may also be accommodated in the box body 110 by directly fixing a plurality of pouch cells 10 in the box body 110.

[0086] In an embodiment of the present invention, the box body 110 may include a first box body and a second box body. The first box body and the second box body are buckled so that a closed space is formed inside the box body 110 to accommodate the battery components 120. Here, "closed" means covering or closing, which may be sealed or non-sealed. The first box body may be a top cover or a bottom plate. For example, the box body 110 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame so that a closed space is formed inside the box body 110 to accommodate the battery components 120.

[0087] In an embodiment of the present invention, the box body 110 may be a part of the chassis structure of the vehicle 1000. For example, a part of the box body 110 may become at least a part of the floor of the vehicle 1000, or a part of the box body 110 may become at least a part of the cross beam and longitudinal beam of the vehicle.

[0088] In an embodiment of the present invention, the pouch cell 10 may be a secondary battery, which refers to a pouch cell 10 that can be activated by charging after discharging; the pouch cell 10 may be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present invention are not limited thereto. The pouch cell 10 may be in a flat body, a cuboid or other shapes, etc., and the embodiments of the present invention are not limited thereto either.

[0089] Please refer to Figures 1 - 3 , the present invention provides a battery device 100, which includes a box body 110 and a battery component 120. The battery component 120 is disposed in the box body 110. The battery component 120 includes a pouch cell 10, a housing 20, and a heating element 30. The housing 20 forms an accommodation space 21 and is connected to the box body 110; the pouch cell 10 is disposed in the accommodation space 21 and is bonded to the box body 110; the heating element 30 is thermally connected to the pouch cell 10 for heating the pouch cell 10.

[0090] Specifically, the outer shell 20 can refer to a component that houses multiple pouch cells 10. Since the housing of the pouch cell 10 is made of a soft material, the housing is relatively soft, with low rigidity and strength, and is easily damaged by external mechanical impacts. The outer shell 20 can provide a relatively strong external protection structure for the multiple pouch cells 10. For example, when the battery device 100 is subjected to mechanical external forces such as collision and extrusion, the outer shell 20 can withstand and disperse these forces, reduce the pressure on the pouch cells 10, and reduce the risk of the pouch cells 10 being punctured, deformed, etc., which is beneficial to protecting the reliability of the pouch cells 10.

[0091] The outer shell 20 can also ensure that the pouch cells 10 are in the correct positions within the box body 110. During the transportation, installation, and use of the battery device 100, the pouch cells 10 may be displaced. The outer shell 20 can better restrain the multiple pouch cells 10, which helps to stably fix the multiple pouch cells 10 at specific positions and keep a reasonable spacing between the pouch cells 10. This is very important for ensuring the stability of the electrical connection inside the battery device 100 and the effective operation of the thermal management system. For example, in the battery device 100, the fixed positions of the pouch cells 10 are beneficial to ensuring the reliable connection of the connecting tabs in series or parallel and the electrodes of the pouch cells 10, and can reduce the risk of poor contact caused by the movement of the pouch cells 10.

[0092] The pouch cell 10 can have a flexible housing. The flexible housing of the pouch cell 10 has good flexibility. The flexible housing can be formed into a bag shape. The electrode assembly of the pouch cell 10 is accommodated in the flexible housing, making the pouch cell 10 a pouch battery. For example, the flexible housing can be an aluminum-plastic film. The pouch cell 10 is bonded to the box body 110, which can further fix the position of the pouch cell 10 and make the position of the pouch cell 10 stable.

[0093] The electrode assembly of the pouch cell 10 can be a wound electrode assembly or a stacked electrode assembly. The electrode assembly can include electrode plates and electrode tabs. The electrode assembly can be formed by winding electrode plates, or the electrode assembly can also be formed by stacking electrode plates.

[0094] The heating element 30 is a component that can generate heat. For example, the heating element 30 can generate heat after being powered on. Another example is that a heat-conducting medium can flow through the heating element 30, and the heat-conducting medium can emit heat to the pouch cells 10 during the process of circulating flow. The heating element 30 can be a heating film.

[0095] The heating element 30 is thermally connected to the pouch cell 10, which means that the heating element 30 can exchange heat with the pouch cell 10. When the temperature of the heating element 30 is relatively high, the heating element 30 can heat the pouch cell 10.

[0096] In the above-mentioned battery device 100, the outer shell 20 can provide mechanical protection outside the plurality of pouch cells 10, reducing the risk of damage to the pouch cells 10 caused by external mechanical impacts, and can also better fix the positions of the plurality of pouch cells 10. Further, the heating element 30 can heat the pouch cells 10 so that the pouch cells 10 can keep their own temperatures within a suitable temperature range under relatively low ambient temperatures, thereby improving the performance reliability of the pouch cells 10. For example, the capacitance of the pouch cells 10 can be increased.

[0097] Please refer to Figures 3 - 6 , in some embodiments of the present utility model, the heating element 30 is at least partially disposed in the accommodation space 21 and is connected to the pouch cell 10. For example Figures 3 - 5 as an example, the heating element 30 can be partially disposed in the accommodation space 21. As Figure 6 shown in the example, the heating element 30 can also be entirely disposed in the accommodation space 21.

[0098] The connection between the heating element 30 and the pouch cell 10 means that the heating element 30 can be in contact with the pouch cell 10 or connected to the pouch cell 10 through an intermediate medium. For example, the heating element 30 can be bonded to the pouch cell 10 by an adhesive. Of course, the heating element 30 can also be bonded to the pouch cell 10 by an adhesive. Since the pouch cell 10 is disposed in the accommodation space 21 and the heating element 30 is at least partially disposed in the accommodation space 21, the distance between the heating element 30 and the pouch cell 10 is closer, and the efficiency of the heating element 30 in heating the pouch cell 10 is higher.

[0099] Please refer to Figure 3 , in some embodiments of the present utility model, the outer shell 20 includes two side walls 22 and a connecting wall 23. The two side walls 22 are disposed opposite to each other, and the connecting wall 23 connects the two side walls 22. The connecting wall 23 and the two side walls 22 together enclose an accommodation space 21.

[0100] Specifically, the two side walls 22 and the connecting wall 23 together form a structure similar to a U shape, and an opening is formed on one side of the two side walls 22 away from the connecting wall 23. The side walls 22 can be perpendicularly disposed with respect to the connecting wall 23. The side walls 22 and the connecting wall 23 can be formed by stamping.

[0101] In the above technical solution, the outer shell 20 formed by the two side walls 22 and the connecting wall 23 makes it easier to install the pouch cell 10 into the accommodation space 21.

[0102] In some embodiments of the present utility model, the outer shell 20 is a metal material part or a non-metal material part. When the outer shell 20 is a metal material part, the metal material may include, but is not limited to, aluminum alloy, stainless steel, iron, etc.; when the outer shell 20 is a non-metal material part, the non-metal material may be, but is not limited to, plastic, composite material, etc.

[0103] In the above technical solution, when the outer shell 20 is a metal material part, it has high strength and rigidity, and can provide good support for the soft-pack battery cell 10; when the outer shell 20 is a non-metal material, while having good strength and rigidity, it is beneficial to reduce weight and take into account economy, and can reduce the weight of the battery device 100 and improve the energy density of the battery device 100.

[0104] In some embodiments of the present utility model, the outer shell 20 of the battery cell is a stainless steel material part or an aluminum material part.

[0105] In the above technical solution, when the outer shell 20 is made of stainless steel, it has high strength and rigidity, and also has good tolerance, is not easy to rust and corrode, is beneficial to maintaining the integrity and stability of the outer shell 20 for a long time, and at the same time the price is relatively low, which can reduce costs; when the outer shell 20 is made of aluminum, it can have a lighter weight on the premise of having the high strength and rigidity of the metal material, which is beneficial to improving the energy density of the battery device 100. The aluminum material also has good thermal conductivity, which is beneficial to heating and heat dissipation of the soft-pack battery cell 10, and also has good corrosion resistance, and can also maintain the integrity and stability of the outer shell 20 for a long time.

[0106] Please refer to Figures 3 - 5 , in some embodiments of the present utility model, the heating element 30 is at least partially connected to the surface of the soft-pack battery cell 10 facing the connecting wall 23. Specifically, the soft-pack battery cell 10 may include a first outer surface 11 and a second outer surface 12 connected to the first outer surface 11. The first outer surface 11 faces the side wall 22, the second outer surface 12 faces the connecting wall 23, the area of the first outer surface 11 is larger than the area of the second outer surface 12, and the heating element 30 is at least partially connected to the second outer surface 12. For example, the heating element 30 may be partially in contact with the second outer surface 12 or may be entirely in contact with the second outer surface 12. At this time, the heating element 30 is at least partially between the second outer surface 12 and the connecting wall 23.

[0107] In the above technical solution, the heating element 30 can heat the soft-pack battery cell 10 through the surface of the soft-pack battery cell 10 facing the connecting wall 23, so that the temperature of the soft-pack battery cell 10 itself is within a suitable temperature range.

[0108] Please refer to Figure 3 and Figure 6, in some embodiments of the present utility model, the heating element 30 is at least partially connected to the surface of the soft-pack battery cell 10 facing away from the connection wall 23. Specifically, the soft-pack battery cell 10 may further include a third outer surface 13 opposite to the second outer surface 12, and the heating element 30 may be at least partially in contact with the third outer surface 13. For example, the heating element 30 may be partially in contact with the third outer surface 13 or entirely in contact with the third outer surface 13.

[0109] In the above technical solution, the heating element 30 can heat the soft-pack battery cell 10 through the surface of the soft-pack battery cell 10 facing away from the connection wall 23, so that the temperature of the soft-pack battery cell 10 itself is within a suitable temperature range.

[0110] Please refer to Figures 3 - 5 , in some embodiments of the present utility model, the heating element 30 is connected to at least two surfaces of the soft-pack battery cell 10. As discussed above, the soft-pack battery cell 10 may include a first outer surface 11, a second outer surface 12, and a third outer surface 13, and the heating element 30 may be connected to at least two of the first outer surface 11, the second outer surface 12, and the third outer surface 13. For example, the heating element 30 may be in contact with the first outer surface 11 and the second outer surface 12. Another example is that the heating element 30 may be in contact with the first outer surface 11 and the third outer surface 13.

[0111] In the above technical solution, the area where the heating element 30 is connected to the soft-pack battery cell 10 is relatively large, which can improve the heating efficiency of the heating element 30 for the soft-pack battery cell 10.

[0112] Please refer to Figure 3 , in some embodiments of the present utility model, the soft-pack battery cell 10 includes a first outer surface 11, a second outer surface 12, and a third outer surface 13. The first outer surface 11 faces the side wall 22, the second outer surface 12 faces the connection wall 23, the third outer surface 13 faces away from the second outer surface 12, and the heating element 30 is connected to the first outer surface 11 and the second outer surface 12, or connected to the first outer surface 11 and the third outer surface 13.

[0113] Specifically, before the soft-pack battery cell 10 expands, the first outer surface 11, the second outer surface 12, and the third outer surface 13 may all be flat surfaces. The first outer surface 11 may be perpendicular to the second outer surface 12.

[0114] In the above technical solution, the heating element 30 is connected to the first outer surface 11 and the second outer surface 12, or connected to the first outer surface 11 and the third outer surface 13, so that the heating element 30 can be connected to at least two surfaces of the soft-pack battery cell 10.

[0115] Please refer to Figure 3 and Figure 4, in some embodiments of the present utility model, the number of soft-pack battery cells 10 is multiple, and the multiple soft-pack battery cells 10 are arranged between two side walls 22. The heating element 30 forms a heating space 31, and the multiple soft-pack battery cells 10 are arranged in the same heating space 31.

[0116] Specifically, the number of soft-pack battery cells 10 in each battery assembly 120 is multiple, and the heating element 30 can be bent to form a heating space 31. For example, the heating element 30 includes a first heating portion 32 and a second heating portion 33. The number of the first heating portions 32 is two, and the two first heating portions 32 are stacked with the side wall 22. The second heating portion 33 connects the two first heating portions 32, and the second heating portion 33 is stacked with the connecting wall 23. The two first heating portions 32 and the second heating portion 33 together enclose a heating space 31.

[0117] In the above technical solution, the multiple soft-pack battery cells 10 are arranged in the same heating space 31, so that the heating element 30 can surround all the soft-pack battery cells 10 in the same battery assembly 120, and it is easier for the heating element 30 to be connected to the soft-pack battery cells 10.

[0118] Please refer to Figure 5 , in some embodiments of the present utility model, the number of soft-pack battery cells 10 is multiple, and the multiple soft-pack battery cells 10 are arranged between two side walls 22. The heating element 30 is wound in a folded shape and forms multiple heating spaces 31, and at least one soft-pack battery cell 10 is arranged in each heating space 31.

[0119] Specifically, the number of heating spaces 31 formed by the heating element 30 wound in a folded shape can be 2, 3, 4, etc. The heating space 31 can be enclosed by two or three heating portions. In the case where the heating space 31 is enclosed by two heating portions, the corresponding soft-pack battery cell 10 is heated by the corresponding two heating portions. Similarly, in the case where the heating space 31 is enclosed by three heating portions, the corresponding soft-pack battery cell 10 is heated by the corresponding three heating portions.

[0120] In the above technical solution, at least one soft-pack battery cell 10 is arranged in each heating space 31, which can increase the contact area between the soft-pack battery cell 10 and the heating element 30, thereby improving the heating efficiency of the heating element 30 for the soft-pack battery cell 10.

[0121] In some embodiments of the present utility model, the resistance of the heating element 30 is X, where 5Ω < X < 80Ω. For example, the resistance X of the heating element 30 can be 6Ω, 7Ω, 15Ω, 20Ω, 70Ω, 78Ω, etc.

[0122] In the above technical solution, when the resistance of the heating element 30 is within the above range, the heating element 30 can not only generate heat quickly, but also keep the heating temperature within a predetermined range, which is beneficial to heating the soft-pack battery cell 10.

[0123] Please refer to Figure 3 , in some embodiments of the present invention, the heating element 30 is integrally sheet-shaped and has a thickness of D, where 0.2 mm < D < 1.5 mm. For example, the thickness D of the heating element 30 can be 0.3 mm, 0.5 mm, 0.8 mm, 1.2 mm, 1.4 mm, etc.

[0124] In the above technical solution, when the thickness of the heating element 30 is within the above range, the heating element 30 is easy to manufacture and occupies a small space in the battery assembly 120, so that the soft-pack battery cell 10 occupies a larger space, and the energy density of the battery assembly 120 can be increased.

[0125] In some embodiments of the present invention, the normal operating temperature of the heating element 30 is T, where 45°C ≤ T ≤ 65°C. For example, T can be 45°C, 48°C, 50°C, 55°C, 60°C, 65°C, etc. The normal operating temperature of the heating element 30 is the temperature of the heating element 30 itself after it generates heat when the rated voltage is applied. The rated voltage can be from 85 volts to 100 volts. For example, the rated voltage is 85 volts, 88 volts, 90 volts, 95 volts, 100 volts, etc.

[0126] In the above technical solution, the operating temperature of the heating element 30 can effectively heat the soft-pack battery cell 10 to increase the temperature of the soft-pack battery cell 10 itself. Furthermore, the soft-pack battery cell 10 can have a higher capacity in a low-temperature environment, and the risk of thermal runaway of the soft-pack battery cell 10 due to excessive temperature can also be reduced.

[0127] In some embodiments of the present invention, when the number of soft-pack battery cells 10 in the accommodation space 21 is greater than 3, 45°C ≤ T ≤ 55°C; and / or, when the number of soft-pack battery cells 10 in the accommodation space 21 is less than or equal to 3, 55°C ≤ T ≤ 65°C.

[0128] In one example, when the number of soft-pack battery cells 10 in the accommodation space 21 is greater than 3, T can be 45°C, 48°C, 50°C, 52°C, 55°C, etc.

[0129] In another example, when the number of soft-pack battery cells 10 in the accommodation space 21 is less than or equal to 3, T can be 55°C, 56°C, 60°C, 62°C, 65°C, etc.

[0130] In the above technical solution, when the number of the soft-pack battery cells 10 is greater than 3, the total heat generated by the soft-pack battery cells 10 themselves is relatively large. Therefore, the operating temperature of the heating element 30 being between 45°C and 55°C can meet the heating requirements of the soft-pack battery cells 10; when the number of the soft-pack battery cells 10 in the accommodation space 21 is less than or equal to 3, the total heat generated by the soft-pack battery cells 10 themselves is relatively small, and the operating temperature of the heating element 30 being between 55°C and 65°C can meet the heating requirements of the soft-pack battery cells 10.

[0131] In some embodiments of the present invention, the heating element 30 is disposed outside the accommodation space 21 and heats the soft-pack battery cells 10 through the outer shell 20. Specifically, the heating element 30 can be attached to the outer shell 20, and the outer shell 20 can be made of a material with good thermal conductivity such as metal, so that the heat can be transferred to the soft-pack battery cells 10 through the outer shell 20. To improve the heating efficiency, the soft-pack battery cells 10 can be in contact with the outer shell 20.

[0132] In the above technical solution, the heating element 30 can heat the soft-pack battery cells 10 through the outer shell 20, so that the temperature of the soft-pack battery cells 10 themselves can be increased.

[0133] In some embodiments of the present invention, the soft-pack battery cell 10 is any one of a lithium iron phosphate battery monomer, a ternary battery monomer, and a solid-state battery monomer.

[0134] Among them, the solid-state battery monomer can be, but is not limited to, a polymer solid-state battery monomer, an oxide solid-state battery monomer, a sulfide solid-state battery monomer, a halide solid-state battery monomer, and the like. The solid-state battery monomer can also be a semi-solid-state battery monomer or a full-solid-state battery monomer.

[0135] In the above technical solution, using the above types for the soft-pack battery cells 10 can provide more choices for the design of the battery device 100 to meet different usage requirements. Among them, when the soft-pack battery cell 10 is a lithium iron phosphate battery monomer, it has the advantages of high reliability, long cycle life, light weight, large capacity, and small internal resistance; when the soft-pack battery cell 10 is a ternary battery monomer, it has the advantages of high energy density and good electrochemical performance; when the soft-pack battery cell 10 is a solid-state battery monomer, it has the advantages of high energy density, high reliability, light weight, and good high and low temperature performance.

[0136] According to some embodiments of the present invention, optionally, the soft-pack battery cell 10 is a lithium iron phosphate battery monomer, and in the positive electrode material of the soft-pack battery cell 10, the dosage ratio of the positive electrode active material, the binder, and the conductive agent is 96:(1 - 3):(1 - 3); the soft-pack battery cell 10 is a ternary battery monomer, and in the positive electrode material of the soft-pack battery cell 10, the dosage ratio of the positive electrode active material, the binder, and the conductive agent is 96:(2 - 3):(1 - 2).

[0137] In some embodiments, the positive electrode of the soft-pack battery cell 10 may be a positive electrode tab, which may include a positive current collector and a positive electrode film layer provided on at least one surface of the positive current collector. The positive electrode film layer includes a positive active material.

[0138] As an example, the positive current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode film layer is provided on either or both of the two opposite surfaces of the positive current collector.

[0139] As an example, the positive current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, titanium, aluminum or stainless steel with silver surface treatment, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0140] As an example, when the soft-pack battery cell 10 of the embodiment of the present utility model is a lithium-ion battery, the positive active material may include at least one of the following materials: phosphate, layered transition metal oxide and their respective modified compounds; optionally, the positive active material may include layered transition metal oxide and their respective modified compounds, which is beneficial to improving the energy density of the soft-pack battery cell 10. However, the present utility model is not limited to these materials, and other conventional materials that can be used as the positive electrode film layer of the battery may also be used. These positive active materials may be used alone or in combination of two or more.

[0141] Examples of the phosphate may include but are not limited to lithium iron phosphate (such as LiFePO 4 (which may also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite material of lithium manganese iron phosphate and carbon, etc.

[0142] The layered transition metal oxide includes a general formula of Li a Ni b Co c M d O e A fAt least one of the compound and its modified compounds. 0.8 ≤ a ≤ 1.2, 0.3 ≤ b < 1, 0 < c < 1, 0 < d < 1, 1 ≤ e ≤ 2, 0 ≤ f ≤ 1, M includes at least one of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B, and A includes at least one of N, F, S, and Cl. Optionally, 0.5 ≤ b < 1, and further optionally, 0.75 ≤ b ≤ 0.98.

[0143] Examples of layered transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO 2 ), lithium nickel oxide (such as LiNiO 2 ), lithium manganese oxide (such as LiMnO 2 , LiMn 2 O 4 ), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 (which can also be abbreviated as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (which can also be abbreviated as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (which can also be abbreviated as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (which can also be abbreviated as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O 2 (which can also be abbreviated as NCM 811 ), LiNi 0.9 Co 0.05 Mn 0.05 O 2 (which can also be abbreviated as Ni90), lithium nickel cobalt aluminum oxide (such as LiNi 0.80 Co 0.15 Al 0.05 O 2 ) and at least one of its modified compounds, etc.

[0144] When the soft-pack battery cell 10 in the embodiment of the present utility model is a sodium-ion battery, the positive electrode active material may include, but is not limited to, at least one of sodium-containing transition metal oxides, polyanion materials (such as phosphates, fluorophosphates, pyrophosphates, sulfates, etc.), and Prussian blue-based materials.

[0145] As an example, the positive electrode active material for a sodium-ion battery may include NaFeO 2 , NaCoO 2 , NaCrO 2 , NaMnO 2 , NaNiO 2 , NaNi 1 / 2 Ti 1 / 2 O 2 , NaNi 1 / 2 Mn 1 / 2 O 2 , Na 2 / 3 Fe 1 / 3 Mn 2 / 3 O 2 , NaNi 1 / 3 Co 1 / 3 Mn 1 / 3 O 2 , NaFePO 4 , NaMnPO 4 , NaCoPO 4 , Prussian blue-based materials, and at least one of the materials with the general formula X p M’ q (PO 4 ) r O x Y 3-x . In the general formula X p M’ q (PO 4 ) r O x Y 3-x , 0 < p ≤ 4, 0 < q ≤ 2, 1 ≤ r ≤ 3, 0 ≤ x ≤ 2, X includes at least one of H+, Li+, Na+, K+, and NH4+, M’ is a transition metal cation, optionally at least one of V, Ti, Mn, Fe, Co, Ni, Cu, and Zn, and Y is a halogen anion, optionally at least one of F, Cl, and Br.

[0146] In the embodiment of the present utility model, the modified compounds of the above-mentioned positive electrode active materials may be doping modification and / or surface coating modification of the positive electrode active materials, such as carbon coating modification, fast ion conductor coating modification, etc.

[0147] During the charge and discharge process of the soft-pack battery cell 10, the insertion and extraction and consumption of active ions such as Li will occur, and the molar content of Li in the soft-pack battery cell 10 is different when it is discharged to different states. In the examples of the present invention regarding the listing of the positive electrode active material, the molar content of Li is the initial state of the material, that is, the state before feeding. When the positive electrode active material is applied to the battery system, after charge and discharge cycles, the molar content of Li may change.

[0148] In the examples of the present invention regarding the listing of the positive electrode active material, the molar content of oxygen O is only the theoretical state value, and the release of oxygen from the lattice will cause the molar content of oxygen O to change. Actually, the molar content of oxygen O will show fluctuations.

[0149] In the examples of the present invention, the content of elements in the positive electrode active material has the meaning well known in the art, and the equipment and methods well known in the art can be used for detection. For example, referring to EPA 6010D-2014, it is tested by inductively coupled plasma atomic emission spectrometry, and determined by inductively coupled plasma optical emission spectrometry (ICP-OES, instrument model: Thermo ICAP7400). First, 0.4 g of the positive electrode active material is weighed, and 10 ml (50% concentration) of aqua regia is added thereto. Then it is placed on a flat plate at 180 °C for 30 min. After digestion on the flat plate, it is fixed to a volume of 100 mL, and quantitative testing is carried out by the standard curve method.

[0150] In some embodiments, the positive electrode can be made of foam metal. The foam metal can be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. When the foam metal is used as the positive electrode, a positive electrode film layer may not be provided on the surface of the foam metal, and of course, a positive electrode film layer may also be provided. As an example, a lithium source material, potassium metal, or sodium metal can also be filled and / or deposited in the foam metal, and the lithium source material is lithium metal and / or lithium-rich material.

[0151] In some embodiments, the positive electrode film layer may also optionally include a positive electrode conductive agent. The present invention does not particularly limit the type of the positive electrode conductive agent. As an example, the positive electrode conductive agent includes at least one of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the mass percentage content of the positive electrode conductive agent in the positive electrode film layer is ≤5 wt%.

[0152] In some embodiments, the positive electrode film layer may further optionally include a positive electrode binder. There is no particular limitation on the type of the positive electrode binder in the embodiments of the present invention. As an example, the positive electrode binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resin. In some embodiments, the mass percentage content of the positive electrode binder in the positive electrode film layer is ≤5 wt%.

[0153] The positive electrode film layer is usually formed by coating a positive electrode slurry on a positive electrode current collector and then drying and cold pressing. The positive electrode slurry is usually formed by dispersing a positive electrode active material, an optional conductive agent, an optional binder, and any other components in a solvent and stirring evenly. The solvent may be N-methylpyrrolidone (NMP), but is not limited thereto.

[0154] In some embodiments, the negative electrode may be a negative electrode plate, and the negative electrode plate may include a negative electrode current collector and a negative electrode film layer provided on at least one surface of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material.

[0155] As an example, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode film layer is provided on any one or both of the two opposite surfaces of the negative electrode current collector.

[0156] As an example, the negative electrode current collector may be a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, titanium, etc. may be used. The foam metal may be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0157] As an example, the negative electrode active material can be the negative electrode active material for the soft package battery cell 10 well-known in the art. As an example, the negative electrode active material can include at least one of the following materials: carbon materials (for example, carbon materials include at least one of artificial graphite, natural graphite, soft carbon, and hard carbon), silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based materials can include at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials can include at least one of elemental tin, tin oxides, and tin alloys. However, the present utility model is not limited to these materials, and other conventional materials that can be used as the battery negative electrode film layer can also be used. These negative electrode film layers can be used alone or in combination of two or more.

[0158] In some embodiments, the negative electrode active material includes silicon element, and the silicon element can exist in the form of silicon-based materials. For example, the silicon-based materials can include at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The introduction of the silicon element can improve the energy density of the soft package battery cell 10.

[0159] In some embodiments, the mass content of the silicon element in the negative electrode film layer is 1 wt% to 32 wt%, optionally 2 wt% to 19 wt%, and further optionally 6 wt% to 13 wt%. In the soft package battery cell 10 system, when the mass content of the silicon element is within the above range, the energy density of the soft package battery cell 10 can be improved.

[0160] In the embodiments of the present utility model, the mass content of the silicon element in the negative electrode film layer has the meaning well-known in the art, and can be detected by using the equipment and methods well-known in the art. For example, the negative electrode pole piece is placed in a solvent such as water for soaking, the negative electrode active material is separated from the negative electrode current collector, and the negative electrode active material is obtained by suction filtration. The negative electrode active material is measured by an inductively coupled plasma - emission spectrometer of model ICAP7400 of Thermo Fisher Scientific Company in the United States, and referring to the standard of GB / T30902-2014, the content of the silicon element can be obtained.

[0161] In some embodiments, the negative electrode film layer may also optionally include a negative electrode conductive agent. The embodiments of the present utility model do not particularly limit the type of the negative electrode conductive agent. As an example, the negative electrode conductive agent can include at least one of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the mass percentage content of the negative electrode conductive agent in the negative electrode film layer is ≤5 wt%.

[0162] In some embodiments, the negative electrode film layer may optionally further include a negative electrode binder. There is no particular limitation on the type of the negative electrode binder in the embodiments of the present invention. As an example, the negative electrode binder may include at least one of styrene-butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (for example, polyacrylic acid PAA, polymethacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS). In some embodiments, the mass percentage content of the negative electrode binder in the negative electrode film layer is ≤5%.

[0163] In some embodiments, the negative electrode film layer may optionally further include other additives. As an example, the other additives may include thickeners, such as sodium carboxymethyl cellulose (CMC-Na), PTC thermistor materials, etc. In some embodiments, the mass percentage content of the other additives in the negative electrode film layer is ≤2wt%.

[0164] In some embodiments, the material of the positive electrode current collector can be aluminum, and the material of the negative electrode current collector can be copper.

[0165] In some embodiments, the separator includes a separator membrane. There is no particular limitation on the type of the separator membrane in the present invention, and any publicly known porous structure separator membrane with good chemical stability and mechanical stability can be selected.

[0166] There is no particular limitation on the type of the separator membrane in the embodiments of the present invention, and any publicly known porous structure separator membrane with good chemical stability and mechanical stability can be selected.

[0167] In some embodiments, the material of the separator membrane may include one or more of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator membrane can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator membrane is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation.

[0168] In some embodiments, the separator membrane may include a porous base film and a coating disposed on at least one side of the porous base film, and the coating may include at least one of inorganic particles or organic particles.

[0169] The porous base film may include one or more of polyethylene and polypropylene.

[0170] The inorganic particles have good heat resistance and can improve the overall heat resistance of the separator membrane. The inorganic particles basically do not undergo oxidation and reduction reactions with metal dendrites within the working voltage range of the sodium-ion battery. In other words, in some embodiments, the inorganic particles include boehmite γ-AlOOH, alumina Al 2 O 3, Aluminum hydroxide Al(OH) 3 , Barium sulfate BaSO 4 , Magnesium oxide MgO, Magnesium hydroxide Mg(OH) 2 , Calcium oxide CaO, Cerium oxide CeO 2 , Strontium titanate SrTiO 3 , Barium titanate BaTiO 3 and Magnesium fluoride MgF 2 One or more of them.

[0171] In some embodiments, the organic particles include at least one of polystyrene, polyethylene, polyimide, melamine resin, phenolic resin, polypropylene, polyester (such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate), polyphenylene sulfide, polyaramide, polyamideimide, polyimide, copolymer of butyl acrylate and ethyl methacrylate, and mixtures thereof.

[0172] In some embodiments, the soft-pack battery cell 10 further includes an electrolyte.

[0173] During the charge and discharge process of the battery cell, active ions are inserted and extracted back and forth between the positive electrode plate and the negative electrode plate, and the electrolyte plays a role in conducting active ions between the positive electrode plate and the negative electrode plate. The embodiments of the present utility model do not have special limitations on the type of the electrolyte, and it can be selected according to actual needs.

[0174] The electrolyte includes an electrolyte salt and a solvent. The types of the electrolyte salt and the solvent are not specifically limited and can be selected according to actual needs.

[0175] In some embodiments, the electrolyte may optionally further include additives. For example, the additives may include negative electrode film-forming additives, may also include positive electrode film-forming additives, and may also include additives that can improve certain battery performance, such as additives for improving the overcharge performance of the battery, additives for improving the high-temperature performance of the battery, additives for improving the low-temperature power performance of the battery, etc.

[0176] For example, the additives include at least one of cyclic carbonate compounds containing unsaturated bonds, sulfate compounds, sulfite compounds, sultone compounds, disulfonic acid compounds, nitrile compounds, aromatic compounds, isocyanate compounds, phosphazene compounds, acid anhydrides, cyclic acid anhydride compounds, phosphite compounds, phosphate compounds, borate esters, and carboxylic ester compounds.

[0177] It is understandable that when the soft-pack battery cell 10 is a lithium iron phosphate battery monomer, in the positive electrode material of the soft-pack battery cell 10, the proportion of the positive electrode active material in the total weight of the positive electrode material is 96 parts, the proportion of the binder in the total weight of the positive electrode material is 1 to 3 parts (for example, it can include but is not limited to 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, etc.), and the proportion of the conductive agent in the total weight of the positive electrode material is 1 to 3 parts (for example, it can include but is not limited to 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, etc.).

[0178] Exemplarily, when the soft-pack battery cell 10 is a lithium iron phosphate battery monomer, the positive electrode active material is LFP (which can refer to LiFePO4, that is, lithium iron phosphate), the binder can be PVDF (polyvinylidene fluoride), and the conductive agent can be conductive carbon black. Among them, LFP:PVDF:conductive carbon black can be 96:2:2. That is to say, the total weight of the positive electrode active material is divided into 100 parts, LFP accounts for 96 parts, PVDF accounts for 2 parts, and conductive carbon black also accounts for 2 parts. Among them, the weight unit of the positive electrode active material can be grams.

[0179] When the soft-pack battery cell 10 is a ternary battery monomer, in the positive electrode material of the soft-pack battery cell 10, the proportion of the positive electrode active material in the total weight of the positive electrode material is 96 parts, the proportion of the binder in the total weight of the positive electrode material is 2 to 3 parts (for example, it can include but is not limited to 2, 2.2, 2.5, 2.8, 3, etc.), and the proportion of the conductive agent in the total weight of the positive electrode material is 1 to 2 parts (for example, it can include but is not limited to 1, 1.2, 1.5, 1.8, 2, etc.). Among them, the ternary battery monomer can be but is not limited to lithium nickel cobalt manganese oxide series, lithium nickel cobalt aluminate series, etc.

[0180] Exemplarily, the ternary material of the ternary battery monomer can be the eight-series LiNi 0.8 Co 0.1 Mn 0.1 O 2 , and the weight ratio of the positive electrode active material, the binder, and the conductive agent is 96:2.5:1.5. That is to say, the total weight of the positive electrode material is divided into 100 parts, the eight-series LiNi 0.8 Co 0.1 Mn 0.1 O 2 accounts for 96 parts, the proportion of the binder is 2.5 parts, and the proportion of the conductive agent is 1.5 parts.

[0181] In the above technical solution, when the soft-pack battery cell 10 is a lithium iron phosphate battery cell, a high proportion of positive electrode active material means that more substances capable of electrochemical reactions can be accommodated in a limited electrode assembly, which is beneficial to increasing the capacity and energy density of the battery device 100, so that the lithium iron phosphate battery cell can output a higher amount of electricity in a relatively small volume and weight, meeting the application scenario with certain requirements for energy density. The amount of binder and conductive agent used in the above range can reduce the cost of auxiliary materials, thereby reducing the overall cost of the battery device 100. When the soft-pack battery cell 10 is a ternary battery cell, since the structure and surface properties of the ternary material itself are relatively complex, the use of the positive electrode active material, binder, and conductive agent in the above-mentioned dosage ratio is beneficial to ensure good bonding between the positive electrode active material particles and between the active material and the current collector, thereby improving the mechanical stability and integrity of the electrode assembly, and is beneficial to reducing the risk of active material shedding and electrode pulverization during charging and discharging, and extending the cycle life of the battery device 100.

[0182] See also Figure 3 In some embodiments of the utility model, the soft-pack battery cell 10 is a ternary battery cell, and the outer shell 20 includes two side walls 22 and a connecting wall 23. The two side walls 22 are arranged opposite to each other, and the connecting wall 23 connects the two side walls 22. The connecting wall 23 and the two side walls 22 together form an accommodating space 21, and the connecting wall 23 is provided with a pressure relief portion 24.

[0183] The pressure relief portion 24 may refer to a structure or component that can be opened to exhaust and release pressure after the pressure inside the housing 20 reaches a preset value. Exemplarily, the pressure relief portion 24 may be an explosion-proof valve.

[0184] The shell 20 is used to accommodate one or more soft-pack battery cells 10. When the soft-pack battery cell 10 experiences thermal runaway, the internal gas expands to a larger volume and causes the shell to rupture, and the gas will be exhausted to release pressure. Since the shell of the soft-pack battery cell 10 usually does not have a pressure relief structure, the exhausted high-temperature gas will run around in the shell 20. If it leaks to the position of the soft-pack battery cell 10 that has not experienced thermal runaway, it will easily affect the reliability of the soft-pack battery cell 10 in a normal state.

[0185] In the above technical solution, when the ternary battery cell undergoes thermal runaway expansion and exhaust pressure relief, the pressure relief portion 24 can guide the exhausted gas to directional pressure relief, thereby reducing the risk of gas chaos affecting the surrounding ternary battery cells, and also reducing the risk of severe thermal runaway of the battery pack composed of the ternary battery cells, which is beneficial to the thermal runaway management of the battery assembly 120 and improves the reliability of the battery assembly 120 composed of the ternary battery cells.

[0186] In some embodiments of the present utility model, the pressure relief part 24 is configured as a pressure relief hole; alternatively, the pressure relief part 24 is configured as a notch; alternatively, the pressure relief part 24 is configured as a weakened part.

[0187] The pressure relief part 24 can be configured as a pressure relief hole. When the soft-pack battery cell 10 exhausts and relieves pressure, causing the internal pressure of the outer shell 20 to increase, the gas can flow to the pressure relief hole to exhaust and relieve pressure outward.

[0188] The notch can refer to structures such as indentations or grooves scratched on the wall of the outer shell 20. When the gas pressure inside the outer shell 20 is relatively high, the position where the notch is located has a lower strength compared to other positions on the wall, and the probability of rupture is relatively high. The gas can break through the position where the notch is located to exhaust and relieve pressure.

[0189] The weakened part can refer to a structure with relatively low strength formed on the wall. For example, the weakened part can refer to an area where the wall thickness of the wall is thinned, or it can also be a structure formed by opening a hole in the wall and covering it with a thin film. When the gas pressure inside the outer shell 20 is relatively high, the probability of rupture of the weakened part is relatively high, and the gas can break through the position where the weakened part is located to exhaust and relieve pressure.

[0190] In the above technical solution, by setting the pressure relief part 24 as a pressure relief hole, a notch or a weakened part, more choices can be provided for the design of the pressure relief part 24 to meet different usage requirements.

[0191] In some embodiments, the number of battery modules 120 is multiple, and the multiple battery modules 120 are arranged along a predetermined direction. In the above battery device 100, the multiple battery modules 120 can increase the capacitance of the battery device 100.

[0192] Please refer to Figure 8 , in some embodiments of the present utility model, the heating elements 30 of the multiple battery modules 120 are connected in series and connected to the bus 40 of the battery device 100. Or rather, all the heating elements 30 are connected in series, and all the heating elements 30 are electrically connected to the bus 40 of the multiple battery devices 100.

[0193] The bus 40 of the battery device 100 is the circuit through which the battery device 100 can charge and discharge the multiple soft-pack battery cells 10. Therefore, in the above technical solution, the multiple heating elements 30 are connected in series, making it easy to manage the heating elements 30. In addition, the heating elements 30 are connected to the bus 40 of the battery device 100, so that the soft-pack battery cells 10 can supply power to the heating elements 30.

[0194] Please refer to Figure 4 and Figure 8, in some embodiments of the present utility model, each heating element 30 includes two connecting wires 34, and a plurality of heating elements 30 are connected through the connecting wires 34 to achieve series connection. Specifically, the connecting wire 34 of the heating element 30 is a wire for the heating element 30 to be energized. For example, one of the connecting wires 34 can be connected to the positive wire of the bus bar 40 of the battery device 100, and the other connecting wire 34 can be connected to the negative wire of the bus bar 40 of the battery device 100.

[0195] The connecting wires 34 of two adjacent heating elements 30 can be connected by means such as welding and winding. The connecting wire 34 can be a copper wire. In the above technical solution, the connecting wire 34 enables the heating elements 30 to be more easily connected in series.

[0196] Please refer to Figure 4 and Figure 5 , in some embodiments of the present utility model, the connecting wire 34 bypasses the edge of the side wall 22, or, as Figure 6 and Figure 9 shown, the connecting wire 34 passes through the side wall 22. Since a plurality of battery assemblies 120 are arranged in sequence, and a plurality of heating elements 30 are connected in series, in order to enable a plurality of heating elements 30 to be effectively connected together, the connecting wire 34 of one heating element 30 can bypass the edge of the side wall 22 and be connected to the connecting wire 34 of the next heating element 30. Alternatively, corresponding through holes can be provided on the side wall 22, so that the connecting wires 34 of two heating elements 30 can pass through the through holes and be connected together.

[0197] In the above technical solution, the connecting wire 34 bypasses the edge of the side wall 22, or the connecting wire 34 passes through the side wall 22, so that the heating elements 30 in a plurality of battery assemblies 120 can be connected in series.

[0198] Please refer to Figure 10 , in some embodiments of the present utility model, the heating element 30 includes a body 35, and two connecting wires 34 are connected to the corners of the body 35 and are respectively on different sides of the body 35. Specifically, a heating wire 36 can be arranged in the body 35. In order to increase the heat generation area of the body 35, the heating wire can be arranged in a meandering shape, and the two ends of the heating wire are respectively located at two corners of the body 35. The two ends of the heating wire are respectively connected to a connecting wire 34. In order to make the heating element 30 easily connected in series, the two connecting wires 34 are respectively on different sides of the body 35. As shown in Fig. 10, one of the connecting wires 34 is located at the corner on the left side of the body 35, and the other connecting wire 34 is located at the corner on the right side of the body 35.

[0199] Thus, in the above technical solution, the position of the connecting wire 34 enables a plurality of heating elements 30 to be more easily connected in series.

[0200] Please refer to Figure 8, in some embodiments of the present utility model, the battery device 100 includes a control switch 50 connected in series between the bus 40 and the heating element 30. It can be understood that when the control switch 50 is closed, the bus 40 of the battery device 100 can supply power to the heating element 30, so that the heating element 30 heats the soft-pack battery cell 10. After the control switch 50 is opened, the bus 40 of the battery device 100 can stop supplying power to the heating element 30, so that the heating element 30 stops heating the soft-pack battery cell 10.

[0201] In the above technical solution, the control switch 50 can realize the control of energizing or de-energizing the heating element 30, thereby controlling the working state of the heating element 30.

[0202] Please refer to Figure 8 , in some embodiments of the present utility model, a plurality of battery assemblies 120 are connected in series and connected to the bus 40. In the above battery assemblies 120, the plurality of battery assemblies 120 are connected in series to the bus 40, which can facilitate the electrical management of the battery assemblies 120.

[0203] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present utility model. The scope of the present utility model is defined by the claims and their equivalents.

Claims

1. A battery device, characterized in that: include: A box and a battery assembly, wherein the battery assembly is arranged in the box, and the battery assembly comprises: A shell, forming a receiving space and connected to the box body, the shell comprising two side walls and a connecting wall, the two side walls are arranged opposite to each other, the connecting wall connects the two side walls, the connecting wall and the two side walls together enclose the receiving space, and the connecting wall is provided with a pressure relief portion; A soft-pack battery cell is arranged in the accommodation space and bonded to the box body; A heating element is thermally connected to the soft-pack battery cell and is used to heat the soft-pack battery cell.

2. The battery device according to claim 1, characterized in that: The heating element is at least partially disposed in the accommodation space and connected to the soft-pack battery cell.

3. The battery device according to claim 2, characterized in that: The heating element is at least partially connected to a surface of the soft-pack battery core facing the connecting wall.

4. The battery device according to claim 2, characterized in that: The heating element is at least partially connected to a surface of the soft-pack battery core facing away from the connecting wall.

5. The battery device according to claim 2, characterized in that: The heating element is connected to at least two surfaces of the soft-pack battery core.

6. The battery device according to claim 5, characterized in that: The soft-pack battery cell includes a first outer surface, a second outer surface and a third outer surface, the first outer surface faces the side wall, the second outer surface faces the connecting wall, and the third outer surface faces away from the second outer surface, and the heating element is connected to the first outer surface and the second outer surface, or to the first outer surface and the third outer surface.

7. The battery device according to claim 5, characterized in that: There are multiple soft-pack battery cells, and the multiple soft-pack battery cells are arranged between the two side walls. The heating element forms a heating space, and the multiple soft-pack battery cells are arranged in the same heating space.

8. The battery device according to claim 5, characterized in that: There are multiple soft-pack battery cells, which are arranged between the two side walls. The heating element is in a folded shape and forms multiple heating spaces, and at least one soft-pack battery cell is arranged in each heating space.

9. The battery device according to any one of claims 1 to 8, characterized in that: The resistance of the heating element is X, wherein 5Ω<X<80Ω.

10. The battery device according to any one of claims 1 to 8, characterized in that: The heating element is in the shape of a sheet as a whole and has a thickness D, wherein 0.2 mm<D<1.5 mm.

11. The battery device according to any one of claims 1 to 8, characterized in that: The normal operating temperature of the heating element is T, wherein 45°C≤T≤65°C.

12. The battery device according to claim 11, characterized in that: When the number of the soft-pack battery cells in the accommodation space is greater than 3, 45°C≤T≤55°C; and / or when the number of the soft-pack battery cells in the accommodation space is less than or equal to 3, 55°C≤T≤65°C.

13. The battery device according to claim 1, characterized in that: The heating element is arranged outside the accommodating space and heats the soft-pack battery cell through the shell; or, the heating element is connected to the soft-pack battery cell.

14. The battery device according to any one of claims 1 to 8, characterized in that: The soft-pack battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell and a solid-state battery cell.

15. The battery device according to claim 1, characterized in that: The pressure relief portion is configured as a pressure relief hole; or, the pressure relief portion is configured as a notch; or, the pressure relief portion is configured as a weakened portion.

16. The battery device according to any one of claims 1 to 8, characterized in that: There are multiple battery assemblies, and the multiple battery assemblies are arranged along a predetermined direction.

17. The battery device according to claim 16, characterized in that: The heating elements of a plurality of the battery assemblies are connected in series and to a bus bar of the battery device.

18. The battery device according to claim 17, characterized in that: Each of the heating elements comprises two connecting wires, and a plurality of the heating elements are connected in series via the connecting wires.

19. The battery device according to claim 18, characterized in that: The connecting line goes around the edge of the side wall, or the connecting line passes through the side wall.

20. The battery device according to claim 19, characterized in that The heating element comprises a body, and the two connecting wires are connected at corners of the body and are respectively located at different sides of the body.

21. The battery device according to claim 17, characterized in that: The battery device includes a control switch connected in series between the bus and the heating element.

22. The battery device according to claim 17, characterized in that: A plurality of the battery assemblies are connected in series and connected to the bus.

23. An electrical equipment, characterized in that: A battery device comprising any one of claims 1-22.

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