Battery device, energy storage device, energy storage system, power utilization device and charging network

Abstract

The utility model discloses a battery device, an energy storage device, an energy storage system, a power utilization device and a charging network. The utility model relates to the technical field of batteries, and solves or relieves the problem of overhigh local temperature of a battery device due to thermal runaway. A parallel connection unit of the battery device comprises a plurality of bag-shaped single batteries which are connected in parallel, a parallel connection loop is arranged between at least two bag-shaped single batteries, and one heat conduction shell correspondingly accommodates the plurality of bag-shaped single batteries in one parallel connection unit. The series unit comprises bag-shaped single batteries which are connected in series to form a series circuit and are respectively positioned in the plurality of parallel units, and the current limiting piece is arranged on any parallel circuit, is positioned outside the series circuit and is used for limiting the current of the corresponding parallel circuit. According to the battery device, the battery device normally works to discharge from the series circuit, and when short circuit or thermal runaway occurs, the current limiting piece on the parallel circuit is used for discharging to limit the current of the corresponding parallel circuit, so that overhigh local temperature of the thermal runaway bag-shaped single battery is avoided.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery device, an energy storage device, an energy storage system, an electrical device and a charging network. Background Art

[0002] In the design of soft-pack batteries, due to the small capacity of the soft-pack batteries themselves and the limitation of the upper voltage limit of the battery system, the battery system often adopts a parallel design of multiple soft-pack batteries.

[0003] When an internal short circuit occurs in a soft-pack battery, its voltage drops, and multiple soft-pack batteries connected in parallel produce short-circuit discharge on the short-circuited soft-pack battery, causing the short-circuited soft-pack battery to heat up, which may lead to the risk of battery loss of control.

[0004] When a single soft-pack battery experiences thermal runaway, the internal active material turns into a resistive conductor. Multiple parallel soft-pack batteries cause short-circuit discharge of the soft-pack battery in thermal runaway, causing the local temperature of the soft-pack battery in thermal runaway to rise, posing a safety hazard to the entire battery system. Utility Model Content

[0005] In view of the above problems, the present application provides a battery device, an energy storage device, an energy storage system, an electric device and a charging network, which can solve or alleviate the problem of excessive local temperature caused by thermal runaway of the battery device.

[0006] In a first aspect, the present application provides a battery device, the battery device comprising:

[0007] a plurality of heat conductive housings;

[0008] A plurality of parallel units, each of which comprises a plurality of pouch-shaped battery cells connected in parallel, wherein one of the heat-conducting housings correspondingly accommodates a plurality of the pouch-shaped battery cells in one of the parallel units;

[0009] A parallel circuit is provided between at least two of the pouch-shaped battery cells in the parallel unit;

[0010] A series unit, wherein the series unit includes the pouch-shaped battery cells connected in series and respectively located in a plurality of the parallel units, and a line between two pouch-shaped battery cells located in different parallel units and connected in series is a series line;

[0011] A plurality of current limiting components are provided on any of the parallel circuits, and the current limiting components are located outside the series circuits; the current limiting components are used to limit the current size of the corresponding parallel circuits.

[0012] In the technical solution of the embodiment of the present application, the battery device discharges from the series circuit when working normally. When the pouch-shaped battery cell is short-circuited or thermally runaway, the other pouch-shaped battery cells discharge the short-circuited or thermally runaway pouch-shaped battery cells through the current limiting device. The current limiting device limits the current of the corresponding parallel circuit, thereby avoiding excessive local temperature of the pouch-shaped battery cell in the thermal runaway state.

[0013] In some embodiments, the thermally conductive housing has at least one open end surface, the battery device includes a cold plate, the open end surface faces the cold plate, and the thermally conductive housing is connected to the cold plate, or the pouch-shaped battery cell is connected to the cold plate for heat dissipation.

[0014] In the above technical solution, the pouch-shaped battery cells generate heat during operation and discharge, and transfer the heat to the heat-conducting housing. The heat-conducting housing has an open end surface, and the cold plate can contact the pouch-shaped battery cells or the open end surface of the heat-conducting housing, so that the cold plate absorbs and releases the heat generated by the pouch-shaped battery cells, thereby maintaining the operating temperature of the battery device at a temperature suitable for operation.

[0015] In some embodiments, a gap is formed between the cold plate and the side of the pouch-shaped battery cell facing the open end surface, and the gap is filled with thermal conductive adhesive.

[0016] In the above technical solution, a space for accommodating the pouch-shaped battery cell is formed in the heat-conducting housing. The heat-conducting housing is fixedly connected to the cold plate, and the pouch-shaped battery cell has a gap on the side facing the open end surface, and the gap is filled with heat-conducting glue. The pouch-shaped battery cell and the cold plate transfer heat through the heat-conducting glue, so that the pouch-shaped battery cell can dissipate heat better.

[0017] In some embodiments, a limiting portion is provided at an end of the open end surface, the limiting portion protrudes from the interior of the heat-conducting housing, and the limiting portion is disposed between the pouch-shaped battery cell and the open end surface.

[0018] In the above technical solution, the end of the open end surface has a limiting portion, and the limiting portion is located between the pouch-shaped battery cell and the open end surface, which can be used to limit the position of the pouch-shaped battery cell to prevent the pouch-shaped battery cell from falling out of the open end surface during the movement and assembly of the battery device.

[0019] In some embodiments, the heat-conductive shell includes two open end surfaces, both of which are formed with the limiting portion, and there is a gap between the pouch-shaped battery cell and the cold plate on the side facing the open end surface, and the gap is filled with thermal conductive adhesive, and the thermal conductive adhesive is at least partially located between the two limiting portions to thermally connect the pouch-shaped battery cell on one side of the limiting portion and the cold plate on the other side of the limiting portion.

[0020] In the above technical solution, a storage space for the pouch-shaped battery cell is formed in the heat-conducting shell, and the storage space is connected to the outside through an opening between two open end faces, and the pouch-shaped battery cell enters the storage space through the opening between the two open end faces. At least part of the thermal conductive adhesive is filled between the limiting parts of the two open end faces, so that the pouch-shaped battery cell and the cold plate located on both sides of the limiting parts can be thermally connected. In this way, the pouch-shaped battery cell is in direct contact with the heat-conducting shell, and is thermally connected to the cold plate through the thermal conductive adhesive, so that the heat dissipation effect of the heat-conducting shell and the cold plate on the pouch-shaped battery cell can be better.

[0021] In some embodiments, the pouch-shaped battery cell includes an electrode lead, the battery device includes a first connector, the first connector is connected to the electrode leads of the pouch-shaped battery cells in different parallel units to form the series circuit, and the current limiting element is connected to the electrode leads of different pouch-shaped battery cells in the same parallel unit to form the parallel circuit.

[0022] In the above technical solution, the electrode lead is used for the electrical connection between the pouch-shaped battery cell and the first connector and the current limiting member. The first connector connects the electrode leads of the pouch-shaped battery cells in different parallel units to form a series circuit. The current limiting member connects the electrode leads of different pouch-shaped battery cells in the same parallel unit to form a parallel loop. In this way, a plurality of pouch-shaped battery cells form a plurality of parallel units and series units. In this way, under normal working conditions, the battery device outputs electrical energy through the series circuit formed by the first connector. In the event that a pouch-shaped battery cell is short-circuited or thermally runaway, the other pouch-shaped battery cells discharge the short-circuited or thermally runaway pouch-shaped battery cells through the current limiting member. The current limiting member limits the current of the parallel loop, thereby avoiding excessive local temperature of the pouch-shaped battery cell in the thermal runaway state.

[0023] In some embodiments, a resistance value of the current limiting element is greater than a resistance value of the first connecting element.

[0024] In the above technical solution, the resistance value of the current limiting component is greater than the resistance value of the first connecting component. When the battery device is working normally, the current will first pass through the first connecting component, and no current will pass through the current limiting component. In this way, when the battery device is working normally, the current limiting component has no effect on the battery device.

[0025] In some embodiments, the first connecting member and the current limiting member are both made of conductive materials, and an insulating layer is disposed between the current limiting member and the first connecting member.

[0026] In the above technical solution, the first connecting member and the current limiting member are both connected to the electrode leads of the pouch-shaped battery cell. Since the end space of the pouch-shaped battery cell is small, an insulating layer is provided between the first connecting member and the current limiting member to avoid direct conduction between the two, thereby causing the battery device to generate heat and consume energy due to the current passing through the current limiting member when working normally.

[0027] In some embodiments, on the same pouch-shaped battery cell, the first connector and the current limiting member are respectively connected to different positions of the same side surface of the electrode lead, or the first connector and the current limiting member are respectively connected to different side surfaces of the electrode lead.

[0028] In the above technical solution, the first connecting member and the current limiting member are respectively connected to the electrode leads of the same pouch-shaped battery cell, and the first connecting member and the current limiting member are spatially isolated so that they are located at different positions on the same side surface of the electrode lead or connected to different side surfaces of the electrode lead, thereby avoiding direct conduction between the first connecting member and the current limiting member.

[0029] In some embodiments, the resistance of the current limiting element is greater than or equal to 0.2Ω, or the current limiting element is used to limit the current of the parallel circuit to be less than or equal to 20A.

[0030] In the above technical solution, the current limiting device is used to limit the current in any parallel circuit to below 20A. In this way, the current in the parallel circuit can be limited to below 20A by making the resistance of the current limiting device greater than or equal to 0.2Ω, thereby avoiding excessive current in the parallel circuit and excessive temperature of the battery device due to short circuit or thermal runaway of the pouch-shaped battery cell.

[0031] In some embodiments, the resistance value of the current limiting element ranges from [0.2Ω, 1000Ω].

[0032] In the above technical solution, the resistance value of the current limiting component is limited to the range of [0.2Ω, 1000Ω], which can limit the current in the parallel circuit to less than 20A. If the resistance value of the current limiting component is too large, it may cause the current limiting component to heat up seriously. Setting the resistance value of the current limiting component within a suitable range can better control the current in the parallel circuit and the heat generated by the current limiting component, thereby avoiding excessive current in the parallel circuit and excessive temperature of the battery device due to short circuit or thermal runaway of the bag-shaped battery cell.

[0033] In some embodiments, the pouch-shaped battery cell includes a main body and an electrode lead, the main bodies of multiple pouch-shaped battery cells in the same thermally conductive shell are arranged side by side along a first direction, the current limiting member is located on one side of the main body along a second direction, and the first direction and the second direction are perpendicular to each other.

[0034] In the above technical solution, the main body parts of the pouch-shaped battery cells are arranged side by side along the first direction, and the current limiting parts are arranged on one side of the main body parts along the second direction, that is, multiple main body parts and multiple current limiting parts are all arranged along the first direction. In this way, it can be avoided that the current limiting parts are clamped between the two main body parts, which may cause the pouch-shaped battery cells to be squeezed and cause the pouch-shaped battery cells to rupture.

[0035] In some embodiments, the pouch-shaped battery cell includes an outer soft shell and an electrode assembly, the electrode assembly includes a pole piece portion and a pole ear portion, and along the first direction, the current limiting member and the pole piece portion are misaligned.

[0036] In the above technical solution, the pouch-shaped battery cell includes an outer soft shell and an electrode assembly, and the outer soft shell is used to accommodate the electrode assembly. Along the first direction, the current limiting member and the pole piece are misaligned to prevent the current limiting member from squeezing the pole piece, resulting in poor contact of the pole piece, thereby causing lithium deposition. Lithium deposition will cause the internal temperature of the battery to rise and the internal resistance of the battery to increase, thereby affecting the capacity and discharge performance of the battery device.

[0037] In some embodiments, the pouch-shaped battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell, and a solid-state battery cell.

[0038] In the above embodiments, in the embodiment where the present application is constructed as a lithium iron phosphate battery cell, the reliability of the pouch-shaped battery cell can be improved and the cycle life of the pouch-shaped battery cell can be extended. In the embodiment where the present application is constructed as a ternary lithium battery cell, the energy density of the pouch-shaped battery cell can be improved and the cruising range can be improved. In the embodiment where the present application is constructed as a solid-state pouch-shaped battery cell, not only the energy density can be improved, but also the reliability can be improved.

[0039] In a second aspect, the present application provides an energy storage device, which includes a plurality of battery devices described in any of the above embodiments, and the battery devices are used to store or provide electrical energy.

[0040] In a third aspect, the present application provides an energy storage system, which includes a power conversion device and the energy storage device described in the above embodiment, wherein the power conversion device is used to electrically connect a power generation device and the energy storage device.

[0041] In a fourth aspect, the present application provides an electrical device, comprising the battery device described in any of the above embodiments, the energy storage device described in the above embodiments, or the energy storage system described in the above embodiments, wherein the battery device, the energy storage device, or the energy storage system is used to provide electrical energy to the electrical device.

[0042] In a fifth aspect, the present application provides a charging network, which includes a charging pile and the energy storage device described in the above embodiment or the energy storage system described in the above embodiment, and the energy storage device or the energy storage system is used to provide electrical energy for the charging pile.

[0043] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0045] Figure 1 A schematic diagram of the structure of an energy storage system in some embodiments of the present application;

[0046] Figure 2 A schematic diagram of the structure of a charging network in some embodiments of the present application;

[0047] Figure 3 A schematic diagram of the structure of a vehicle according to some embodiments of the present application;

[0048] Figure 4 A schematic diagram of the exploded structure of a battery device according to some embodiments of the present application;

[0049] Figure 5 A schematic diagram of the structure of a battery device according to some embodiments of the present application;

[0050] Figure 6 Another schematic diagram of the structure of a battery device according to some embodiments of the present application;

[0051] Figure 7 Another exploded structural schematic diagram of a battery device according to some embodiments of the present application;

[0052] Figure 8 This is another schematic diagram of the structure of a battery device according to some embodiments of the present application.

[0053] The reference numerals in the specific implementation manner are as follows:

[0054] Vehicles 1000;

[0055] Battery device 100, controller 200, motor 300;

[0056] Heat-conducting housing 10, open end surface 11, limiting portion 111,

[0057] Parallel unit 20, pouch-shaped battery cell 21, main body 212;

[0058] Series unit 30;

[0059] Current limiting element 40;

[0060] Cold plate 50, thermal conductive adhesive 51;

[0061] A first connecting member 60;

[0062] Box body 70, first part 71, second part 72;

[0063] Energy storage device 1, power conversion device 2, power generation equipment 3, charging pile 4, connector 5. DETAILED DESCRIPTION

[0064] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0066] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0067] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent 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.

[0068] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0069] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0070] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0071] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like 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 a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship 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 the specific circumstances.

[0072] With the rapid development of new energy technologies around the world, the application scope of power batteries, as key energy storage devices, is expanding at an unprecedented rate. It is not only an indispensable energy storage solution in renewable energy power stations such as hydropower, thermal power, wind power and solar power, but also deeply integrated into the field of electric transportation, becoming the core power source for green travel modes such as electric bicycles, electric motorcycles and even electric cars.

[0073] As a key component of new energy technology, power batteries are increasingly being used and their market demand is growing. Power batteries play an indispensable role in renewable energy, electric transportation, military equipment, aerospace and other fields.

[0074] With the development of power battery technology, there are increasingly higher requirements for the energy density of power batteries, and soft-pack batteries have gradually become an important application type in power batteries. The shell of soft-pack batteries uses aluminum-plastic composite film. Due to the lightweight characteristics of aluminum-plastic film, soft-pack batteries are lighter at the same capacity, so the energy density is higher.

[0075] In the design of soft-pack batteries, due to the small capacity of the soft-pack batteries themselves and the limitation of the upper voltage limit of the battery system, the battery system often adopts a parallel design of multiple soft-pack batteries.

[0076] When an internal short circuit occurs in a soft-pack battery, its voltage drops, and multiple soft-pack batteries connected in parallel produce short-circuit discharge on the short-circuited soft-pack battery, causing the short-circuited soft-pack battery to heat up, which may lead to the risk of battery loss of control.

[0077] When a single soft-pack battery experiences thermal runaway, the internal active material turns into a resistive conductor. Multiple parallel soft-pack batteries cause short-circuit discharge of the soft-pack battery in thermal runaway, causing the local temperature of the soft-pack battery in thermal runaway to rise, posing a safety hazard to the entire battery system.

[0078] Based on the above considerations, in order to solve or alleviate the problem of excessively high local temperature in thermal runaway of a battery device, the present application provides a battery device, the battery device comprising:

[0079] a plurality of heat conductive housings;

[0080] A plurality of parallel units, each of which comprises a plurality of pouch-shaped battery cells connected in parallel, and a heat-conducting housing correspondingly accommodates a plurality of pouch-shaped battery cells in one parallel unit;

[0081] A parallel circuit is provided between at least two pouch-shaped battery cells in the parallel unit;

[0082] A series unit includes pouch-shaped battery cells connected in series and respectively located in a plurality of parallel units, wherein a line between two pouch-shaped battery cells located in different parallel units and connected in series is a series line;

[0083] Multiple current limiting components are provided on any parallel circuit, and the current limiting components are located outside the series circuit; the current limiting components are used to limit the current size of the corresponding parallel circuit.

[0084] In such a battery device, the battery device discharges from the series circuit when operating normally. In the event of thermal runaway of the pouch-shaped battery cells, the other pouch-shaped battery cells discharge the pouch-shaped battery cells in thermal runaway through the current limiting device. The current limiting device is used to limit the current size of the corresponding parallel circuit, thereby avoiding the pouch-shaped battery cells in the thermal runaway state from being too hot and causing thermal runaway.

[0085] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, in parallel or in mixed connection through a busbar component.

[0086] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells.

[0087] As an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells by a cable tie.

[0088] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are accommodated in the case.

[0089] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0090] As an example, the battery cell assembly may also be housed in the case by directly fixing a plurality of battery cells to the case.

[0091] As an example, the box may include a first box and a second box. The first box and the second box are buckled together to form a closed space inside the box to accommodate the battery cell assembly. The closed here means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0092] As an example, the box body 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 to accommodate the battery cell assembly.

[0093] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0094] The technical solutions described in the embodiments of the present application are applicable to various electrical devices using battery cells, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecrafts, etc. The embodiments of the present application provide an energy storage device, including one or more battery clusters (Battery Cluster) to increase the voltage and capacity of the energy storage device. The battery cluster may include multiple battery devices, and the multiple battery devices are connected in series through a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device.

[0095] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0096] Please refer to Figure 3 , Figure 3 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used to power 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 also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0097] In some embodiments of the present application, the battery device 100 can not only serve as an operating power source for the vehicle 1000, but also serve 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.

[0098] Please refer to Figure 4 , Figure 4 Schematic diagram of the exploded structure of the battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box 70 and an energy unit, and the energy unit is contained in the box 70. Among them, the box 70 is used to provide a closed space for the energy unit, and the box 70 can adopt a variety of structures. In some embodiments, the box 70 may include a first part 71 and a second part 72, the first part 71 and the second part 72 cover each other, and the first part 71 and the second part 72 jointly define a closed space for accommodating the energy unit. The second part 72 can be a hollow structure with one end open, and the first part 71 can be a plate-like structure. The first part 71 covers or buckles the open side of the second part 72, so that the first part 71 and the second part 72 jointly define a closed space; the first part 71 and the second part 72 can also be hollow structures with one side open, and the open side of the first part 71 covers or buckles the open side of the second part 72. Of course, the box 70 formed by the first part 71 and the second part 72 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0099] In some embodiments, Figure 5 and Figure 6 As shown, the present application provides a battery device 100 , which includes a plurality of heat-conducting housings 10 , a plurality of parallel units 20 , a series unit 30 , and a plurality of current limiting members 40 .

[0100] The parallel unit 20 includes a plurality of pouch-shaped battery cells 21 connected in parallel. One heat-conducting housing 10 correspondingly accommodates a plurality of pouch-shaped battery cells 21 in one parallel unit 20 . A parallel circuit is formed between at least two pouch-shaped battery cells 21 in the parallel unit 20 .

[0101] The series unit 30 includes pouch-shaped battery cells 21 connected in series and respectively located in a plurality of parallel units 20 , and a line between two pouch-shaped battery cells 21 located in different parallel units 20 and connected in series is a series line.

[0102] A current limiting element 40 is provided on any parallel circuit, and the current limiting element 40 is located outside the series circuit. The current limiting element 40 is used to limit the current size of the corresponding parallel circuit.

[0103] In the technical solution of the embodiment of the present application, the battery device 100 discharges from the series circuit when working normally. When the pouch-shaped battery cell 21 is in thermal runaway, the other pouch-shaped battery cells 21 discharge the pouch-shaped battery cell 21 in thermal runaway through the current limiting device 40. The current limiting device 40 is used to limit the current of the corresponding parallel circuit, thereby avoiding the over-high temperature of the pouch-shaped battery cell 21 in thermal runaway state.

[0104] Specifically, the battery device 100 includes a plurality of pouch-shaped battery cells 21. As an example, the electrode assembly of the pouch-shaped battery cells 21 is contained in an aluminum-plastic film packaging bag, and the edges of the packaging bag can be connected by heat-pressing sealing to form a sealing portion, and the electrode lead-out portion extends to the outside of the packaging bag to realize the charging and discharging of the battery cells.

[0105] Since the pouch-shaped battery cells 21 are not easy to group, a hard shell is usually configured outside the pouch-shaped battery cells 21 for grouping. However, configuring a single pouch-shaped battery cell 21 with a single hard shell will affect the grouping efficiency or space utilization and overall capacity of the battery. Therefore, multiple pouch-shaped battery cells 21 are usually electrically connected and packaged in a hard shell, which is convenient for grouping the pouch-shaped battery cells 21 and can improve the grouping efficiency, space utilization and overall capacity of the battery.

[0106] Furthermore, the hard shell is made of a material with good thermal conductivity to form a thermally conductive shell 10. The thermally conductive shell 10 can contain and protect the pouch-shaped battery cells 21 while effectively conducting the heat generated inside the battery to the outside, keeping the battery within a suitable operating temperature range and improving the working efficiency and cycle life of the battery.

[0107] Optionally, the heat-conducting housing 10 includes a metal heat-conducting housing 10, such as an aluminum alloy heat-conducting housing 10, which has high strength, good thermal conductivity and corrosion resistance. The aluminum alloy housing can be made by extrusion, welding and other processes.

[0108] Optionally, the heat-conducting shell 10 includes a composite heat-conducting shell 10, such as a carbon fiber reinforced plastic (CFRP) heat-conducting shell 10 and a glass fiber reinforced plastic (GFRP) heat-conducting shell 10. The composite material is light, high-strength and has good thermal conductivity, which can further reduce the weight of the battery device 100 and improve the energy density of the battery device 100.

[0109] However, if multiple pouch-shaped battery cells 21 are encapsulated in a heat-conducting shell 10, the multiple pouch-shaped battery cells 21 connected in parallel are prone to internal short circuits, causing the heat of the multiple pouch-shaped battery cells 21 in one heat-conducting shell 10 to accumulate in a short period of time, and it is difficult to transfer the heat to the outside in time, resulting in heat spread between the multiple pouch-shaped battery cells 21 in the heat-conducting shell 10, or even heat spread between different heat-conducting shells 10.

[0110] Based on the above problems, a current limiting component 40 is provided in any parallel circuit of multiple pouch-shaped battery cells 21 in a heat-conducting shell 10, which can reduce the probability of a large amount of heat concentrated in a short period of time due to an internal short circuit, thereby enabling multiple pouch-shaped battery cells 21 to be packaged in one heat-conducting shell 10, and the heat-conducting shell 10 facilitates timely dissipation of heat, thereby reducing the probability of heat spread between multiple pouch-shaped battery cells 21.

[0111] The parallel unit 20 includes a plurality of pouch-shaped battery cells 21, which are connected in parallel to form a parallel circuit between at least two pouch-shaped battery cells 21. The plurality of pouch-shaped battery cells 21 in one parallel unit 20 are accommodated in one heat-conducting housing 10.

[0112] The series unit 30 includes pouch-shaped battery cells 21 located in different parallel units 20 connected in series, and a line between two pouch-shaped battery cells 21 connected in series is a series line.

[0113] The current limiting element 40 is arranged in each parallel circuit to limit the current in the corresponding parallel circuit. Thus, when current flows through the parallel circuit, the current value may be less than or equal to the current value limited by the current limiting element 40 .

[0114] At the same time, the current limiting element 40 is located outside the series circuit, and the two ends of the current limiting element 40 are equal voltage points. Therefore, when the battery device 100 is in normal working state, the current is discharged through the series circuit instead of the parallel circuit, and the current limiting element 40 has no effect on the current size in the series circuit.

[0115] When an internal short circuit occurs in a pouch-shaped battery cell 21 in the battery device 100 , the current is discharged through the parallel circuit, and the current limiting element 40 limits the current in the corresponding parallel circuit, thereby preventing the local temperature of the pouch-shaped battery cell 21 in the thermal runaway state from being too high.

[0116] In one embodiment, Figure 6 As shown, the battery device 100 includes two parallel units 20, each of which includes four pouch-shaped battery cells 21. The four pouch-shaped battery cells 21 are connected in parallel to form three parallel circuits. The four pouch-shaped battery cells 21 in the two parallel units 20 are connected in series in pairs to form four series routes. A current limiting member 40 is provided in each parallel circuit.

[0117] In this way, when the battery device 100 is in normal working state, the current is discharged through four series circuits instead of through the parallel circuit, and the current limiting component 40 has no effect on the current size in the series circuit. When a pouch-shaped battery cell 21 of the battery device 100 has an internal short circuit, the other pouch-shaped battery cells 21 discharge through the parallel circuit, and the current limiting component 40 limits the current size in the corresponding parallel circuit, thereby avoiding the local temperature of the pouch-shaped battery cell 21 in the thermal runaway state from being too high.

[0118] In some embodiments, Figure 7 As shown, the heat-conducting housing 10 has at least one open end surface 11 , the battery device 100 includes a cold plate 50 , the open end surface 11 faces the cold plate 50 , and the heat-conducting housing 10 is connected to the cold plate 50 , or the pouch-shaped battery cell 21 is connected to the cold plate 50 for heat dissipation.

[0119] In the above technical solution, the pouch-shaped battery cells 21 generate heat during operation and discharge, and transfer the heat to the heat-conducting housing 10. The heat-conducting housing 10 has an open end surface 11, and the cold plate 50 can contact the pouch-shaped battery cells 21 or the open end surface 11 of the heat-conducting housing 10, so that the cold plate 50 absorbs and releases the heat generated by the pouch-shaped battery cells 21, thereby maintaining the operating temperature of the battery device 100 at a temperature suitable for operation.

[0120] Specifically, the cold plate 50 contacts the heat-conducting housing 10 or the pouch-shaped battery cells 21 in the heat-conducting housing 10 at a side close to the open end surface 11 of the heat-conducting housing 10 , and absorbs and releases heat generated by the pouch-shaped battery cells 21 .

[0121] In some embodiments, Figure 8 As shown, there is a gap between the pouch-shaped battery cell 21 and the cold plate 50 on the side facing the open end surface 11 , and the gap is filled with a thermal conductive adhesive 51 .

[0122] In the above technical solution, a space for accommodating the pouch-shaped battery cell 21 is formed in the heat-conducting housing 10. The heat-conducting housing 10 is fixedly connected to the cold plate 50, and the pouch-shaped battery cell 21 has a gap on the side facing the open end surface 11, and the gap is filled with a heat-conducting adhesive 51. The pouch-shaped battery cell 21 and the cold plate 50 transfer heat through the heat-conducting adhesive 51, so that the pouch-shaped battery cell 21 can dissipate heat better.

[0123] Specifically, the thermally conductive adhesive 51 is a single-component, thermally conductive, room temperature curing organic silicone adhesive sealant, which undergoes a condensation reaction with moisture in the air to release low molecular weight molecules to cause cross-linking and curing, thereby vulcanizing into a high-performance elastomer.

[0124] Thermally conductive adhesive 51 has excellent resistance to hot and cold alternation, aging resistance and electrical insulation performance, and has excellent moisture resistance, shock resistance, corona resistance, leakage resistance and chemical medium resistance.

[0125] The thermal conductive adhesive 51 can be continuously used at -60 to 280° C. and maintains performance, does not swell, and has good adhesion to most metal and non-metal materials.

[0126] The gap between the pouch-shaped battery cell 21 and the cold plate 50 is filled with a thermally conductive adhesive 51, which can fix the relative position between the cold plate 50 and the pouch-shaped battery cell 21, preventing the pouch-shaped battery cell 21 from moving in the heat-conducting housing 10 and damaging the electrical connection structure of the battery device 100. On the other hand, the pouch-shaped battery cell 21 can be thermally connected to the cold plate 50 to achieve a better heat dissipation effect.

[0127] In some embodiments, Figure 8 As shown, a limiting portion 111 is disposed at the end of the open end surface 11 . The limiting portion 111 protrudes from the interior of the heat-conducting housing 10 . The limiting portion 111 is disposed between the pouch-shaped battery cell 21 and the open end surface 11 .

[0128] In the above technical solution, the end of the open end surface 11 has a limiting portion 111, and the limiting portion 111 is located between the pouch-shaped battery cell 21 and the open end surface 11, which can be used to limit the position of the pouch-shaped battery cell 21 to prevent the pouch-shaped battery cell 21 from falling out of the open end surface 11 during the movement and assembly of the battery device 100.

[0129] Specifically, the limiting portion 111 is arranged at the end of the open end surface 11 and protrudes toward the interior of the heat-conducting shell 10. The pouch-shaped battery cell 21 is accommodated inside the heat-conducting shell 10. When the pouch-shaped battery cell 21 moves toward the open end surface 11 in the heat-conducting shell 10, the limiting portion 111 can block the continuous movement of the pouch-shaped battery cell 21. In this way, it can be prevented that the pouch-shaped battery cell 21 falls out from one side of the open end surface 11 when the heat-conducting shell 10 accommodating the pouch-shaped battery cell 21 is moved or assembled.

[0130] In some embodiments, Figure 8As shown, the heat-conducting shell 10 includes two open end surfaces 11, and the two open end surfaces 11 are each formed with a limiting portion 111. There is a gap between the pouch-shaped battery cell 21 and the cold plate 50 on the side facing the open end surface 11, and the gap is filled with a thermal conductive adhesive 51. The thermal conductive adhesive 51 is at least partially located between the two limiting portions 111 to thermally connect the pouch-shaped battery cell 21 located on one side of the limiting portion 111 and the cold plate 50 located on the other side of the limiting portion 111.

[0131] In the above technical solution, a storage space for the pouch-shaped battery cell 21 is formed in the heat-conductive shell 10, and the storage space is connected to the outside through the opening between the two open end faces 11, and the pouch-shaped battery cell 21 enters the storage space through the opening between the two open end faces 11. At least part of the thermal conductive adhesive 51 is filled between the limiting portions 111 of the two open end faces 11, so that the pouch-shaped battery cell 21 and the cold plate 50 located on both sides of the limiting portions 111 can be thermally connected. In this way, the pouch-shaped battery cell 21 is in direct contact with the heat-conductive shell 10, and is thermally connected to the cold plate 50 through the thermal conductive adhesive 51, so that the heat dissipation effect of the heat-conductive shell 10 and the cold plate 50 on the pouch-shaped battery cell 21 can be better.

[0132] Specifically, the heat-conducting housing 10 is U-shaped, has two open end faces 11, and has an accommodation space for the pouch-shaped battery cell 21 formed therein. The accommodation space is connected to the outside through the openings of the two open end faces 11, and the pouch-shaped battery cell 21 is placed in the accommodation space through the openings. The cold plate 50 is connected to the two open end faces 11 to close the opening of the heat-conducting housing 10, thereby closing the pouch-shaped battery cell 21 in the accommodation space of the heat-conducting housing 10.

[0133] The heat-conductive shell 10 is bonded to the pouch-shaped battery cells 21. When there are multiple pouch-shaped battery cells 21 in the heat-conductive shell 10, the multiple pouch-shaped battery cells 21 are arranged along a first direction, and the multiple pouch-shaped battery cells 21 are bonded to each other to bond and fix them together, and to fix the pouch-shaped battery cells 21 in the heat-conductive shell 10.

[0134] As an example, adhesive is used to bond the heat-conducting housing 10 to the pouch-shaped battery cells 21 and to bond adjacent pouch-shaped battery cells 21. The adhesive may be insulating to insulate the heat-conducting housing 10 from the pouch-shaped battery cells 21.

[0135] In some embodiments, Figure 5 and Figure 6 As shown, the pouch-shaped battery cell 21 includes an electrode lead, and the battery device 100 includes a first connector 60, the first connector 60 is connected to the electrode leads of the pouch-shaped battery cells 21 in different parallel units 20 to form a series circuit, and the current limiting member 40 is connected to the electrode leads of different pouch-shaped battery cells 21 in the same parallel unit 20 to form a parallel loop.

[0136] In the above technical solution, the electrode lead is used for the electrical connection between the pouch-shaped battery cell 21 and the first connector 60 and the current limiting member 40. The first connector 60 connects the electrode leads of the pouch-shaped battery cells 21 in different parallel units 20 to form a series circuit. The current limiting member 40 connects the electrode leads of different pouch-shaped battery cells 21 in the same parallel unit 20 to form a parallel loop. In this way, a plurality of pouch-shaped battery cells 21 form a plurality of parallel units 20 and a series unit 30.

[0137] Under normal working conditions, the battery device 100 outputs electric energy through the series circuit formed by the first connecting member 60. In the event of thermal runaway of a certain pouch-shaped battery cell 21, other pouch-shaped battery cells 21 discharge the pouch-shaped battery cell 21 in thermal runaway through the current limiting member 40. The current limiting member 40 limits the current of the parallel circuit, thereby preventing the temperature of the pouch-shaped battery cell 21 in thermal runaway from being too high.

[0138] Specifically, the pouch-shaped battery cell 21 includes electrode leads, which may be led out in two directions of the soft shell of the pouch-shaped battery cell 21, or may be led out only on one side of the soft shell of the pouch-shaped battery cell 21. In the illustrated example, the electrode leads are led out in two directions of the pouch-shaped battery cell 21 (e.g., Figure 6 in the Y-axis direction).

[0139] The first connector 60 is used to connect the pouch-shaped battery cells 21 in two parallel units 20 in series to form a series circuit between every two pouch-shaped battery cells 21 connected in series.

[0140] Optionally, the first connector 60 may be a conductive wire directly connected to the electrode leads of the two pouch-shaped battery cells 21 to achieve series connection between the two pouch-shaped battery cells 21. When the battery device 100 is operating normally, current flows in the series circuit, and the series circuit is formed by connecting the wires, which can reduce energy loss in the series circuit.

[0141] Optionally, the electrode leads of two pouch-shaped battery cells 21 may be directly welded to form the first connector 60 . In this way, the connection method is simple and reliable, easy to implement, and can reduce energy loss in the series circuit.

[0142] The current limiting member 40 is used to connect the plurality of pouch-shaped battery cells 21 in parallel to form a parallel loop between the plurality of pouch-shaped battery cells 21 .

[0143] Optionally, the current limiting component 40 includes a metal structure, which is connected to two pouch-shaped battery cells 21 to form a parallel circuit, and has a certain resistance value, which can limit the current size in the parallel circuit.

[0144] Optionally, the current limiting element 40 includes a resistor directly connected to the electrode lead. The resistor with a certain resistance is connected to two pouch-shaped battery cells 21 to form a parallel circuit, which can limit the current size in the parallel circuit.

[0145] In one embodiment, the battery device 100 includes a busbar, which includes a first connector 60 and a current limiting member 40. The first connector 60 and the current limiting member 40 are insulated from each other. The electrode leads of the pouch-shaped battery are respectively connected to the first connector 60 and the current limiting member 40, so that the connection between the busbar and the pouch-shaped battery can be achieved.

[0146] In some embodiments, the resistance value of the current limiting member 40 is greater than the resistance value of the first connecting member 60 .

[0147] In the above technical solution, the resistance value of the current limiting member 40 is greater than the resistance value of the first connecting member 60. When the battery device 100 works normally, the current first passes through the first connecting member 60, and no current passes through the current limiting member 40. In this way, when the battery device 100 works normally, the current limiting member 40 has no effect on the battery device 100.

[0148] Specifically, the resistance value of the current limiting member 40 is greater than the resistance value of the first connector 60, so that when the battery device 100 works normally, the current loss in the series circuit is small. In the case of thermal runaway of a certain pouch-shaped battery cell 21, other pouch-shaped battery cells 21 discharge the pouch-shaped battery cell 21 in thermal runaway through the current limiting member 40. In the parallel circuit, the current flowing therein is controlled to be small by a larger resistance value, thereby preventing the pouch-shaped battery cell 21 in thermal runaway state from being overheated.

[0149] In some embodiments, the first connecting member 60 and the current limiting member 40 are both made of conductive materials, and an insulating layer is disposed between the current limiting member 40 and the first connecting member 60 .

[0150] In the above technical solution, the first connector 60 and the current limiting member 40 are both connected to the electrode leads of the pouch-shaped battery cell 21. Since the end space of the pouch-shaped battery cell 21 is small, an insulating layer is provided between the first connector 60 and the current limiting member 40 to avoid direct conduction between the two, thereby causing the battery device 100 to generate heat and consume energy due to the current passing through the current limiting member 40 when working normally.

[0151] Specifically, the first connecting member 60 and the current limiting member 40 are both made of conductive materials to achieve electrical connection between the pouch-shaped battery cells 21.

[0152] Optionally, an insulating spacer is provided between the first connector 60 and the current limiting component 40 as an insulating layer. The insulating spacer may be made of polyimide, polypropylene, polyethylene, polycarbonate or polyurethane foam, silicone foam, etc. The above materials have good heat resistance, insulation and certain mechanical strength to ensure the insulation reliability between the first connector 60 and the current limiting component 40.

[0153] Optionally, an insulating coating may be provided as an insulating layer on the surfaces of the first connector 60 and the current limiting member 40 facing each other, so as to achieve insulation between the first connector 60 and the current limiting member 40 .

[0154] In some embodiments, on the same pouch-shaped battery cell 21 , the first connector 60 and the current limiting member 40 are respectively connected to different positions of the same side surface of the electrode lead, or the first connector 60 and the current limiting member 40 are respectively connected to different side surfaces of the electrode lead.

[0155] In the above technical solution, the first connecting member 60 and the current limiting member 40 are respectively connected to the electrode leads of the same pouch-shaped battery cell 21, and the first connecting member 60 and the current limiting member 40 are spatially isolated so that they are located at different positions on the same side surface of the electrode lead or connected to different side surfaces of the electrode lead, thereby avoiding direct conduction between the first connecting member 60 and the current limiting member 40.

[0156] Specifically, the first connecting member 60 and the current limiting member 40 are insulated from each other. In order to ensure the reliability of the insulation, the first connecting member 60 and the current limiting member 40 are spatially isolated, thereby avoiding direct conduction between the first connecting member 60 and the current limiting member 40.

[0157] In some embodiments, the resistance of the current limiting element 40 is greater than or equal to 0.2Ω, or the current limiting element 40 is used to limit the current of the parallel circuit to be less than or equal to 20A.

[0158] In the above technical solution, the current limiting component 40 is used to limit the current in any parallel circuit to below 20A. In this way, the current in the parallel circuit can be limited to below 20A by making the resistance of the current limiting component 40 greater than or equal to 0.2Ω, thereby avoiding the local temperature of the battery device 100 being too high due to excessive current in the parallel circuit caused by short circuit or thermal runaway of the pouch-shaped battery cell 21.

[0159] Specifically, the greater the resistance of the current limiting component 40 is, the smaller the current in the parallel circuit is. Thus, the resistance of the current limiting component 40 can be controlled according to actual needs, thereby controlling the current in the parallel circuit within a reasonable range.

[0160] In some embodiments, the resistance of the current limiting element 40 ranges from [0.2Ω, 1000Ω].

[0161] In the above technical solution, the resistance value of the current limiting element 40 is limited to the range of [0.2Ω, 1000Ω], which can limit the current in the parallel circuit to less than 20A. If the resistance value of the current limiting element 40 is too large, it may cause the current limiting element 40 to heat up seriously. Setting the resistance value of the current limiting element 40 within a suitable range can better control the current in the parallel circuit and the heat generated by the current limiting element 40, thereby avoiding excessive current in the parallel circuit when the pouch-shaped battery cell 21 is short-circuited or thermally runaway, which may cause the local temperature of the battery device 100 to be too high.

[0162] Specifically, when the resistance of the current limiting element 40 is too small, the parallel circuit cannot be effectively current limited, and when the resistance of the current limiting element 40 is too large, the current limiting element 40 may be seriously heated.

[0163] Therefore, the resistance of the current limiting element 40 can be 0.2Ω, 1Ω, 5Ω, 10Ω, 50Ω, 100Ω, 200Ω, 500Ω, 800Ω or 1000Ω, or any other value in the range of [0.2Ω, 1000Ω]. This can better control the current in the parallel circuit and the heat generated by the current limiting element 40, and avoid excessive current in the parallel circuit and excessive temperature of the battery device 100.

[0164] In some embodiments, the pouch-shaped battery cell 21 includes a main body 212 and an electrode lead. The main bodies 212 of multiple pouch-shaped battery cells 21 in the same heat-conducting shell 10 are arranged side by side along a first direction, and the current limiting member 40 is located on one side of the main body 212 along a second direction. The first direction and the second direction are perpendicular to each other.

[0165] In the above technical solution, the main body 212 of the pouch-shaped battery cell 21 is arranged side by side along the first direction, and the current limiting member 40 is arranged on one side of the main body 212 along the second direction, that is, multiple main body 212 and multiple current limiting members 40 are all arranged along the first direction. In this way, it can be avoided that the current limiting member 40 is clamped between the two main body 212, which causes the pouch-shaped battery cell 21 to be squeezed and cause the pouch-shaped battery cell 21 to rupture.

[0166] Specifically, Figure 6 As shown, the battery device 100 includes a plurality of parallel units 20, each of which includes a plurality of pouch-shaped battery cells 21, the main bodies 212 of the plurality of pouch-shaped battery cells 21 are arranged side by side along a first direction, and the plurality of pouch-shaped battery cells 21 are connected in parallel to form a parallel circuit, and a current limiting member 40 is provided in each parallel circuit, and the current limiting member 40 is located on one side of the main body 212 along a second direction, so that the current limiting member 40 can be prevented from being sandwiched between two main bodies 212. The first direction is the X-axis direction in the figure, and the second direction is the Y-axis direction in the figure.

[0167] In some embodiments, the pouch-shaped battery cell 21 includes an outer soft shell and an electrode assembly, the electrode assembly includes a pole piece portion and a pole ear portion, and along the first direction, the current limiting member 40 and the pole piece portion are misaligned.

[0168] In the above technical solution, the bag-shaped battery cell 21 includes an outer soft shell and an electrode assembly, and the outer soft shell is used to accommodate the electrode assembly. The current limiting member 40 and the pole piece are misaligned along the first direction to prevent the current limiting member 40 from squeezing the pole piece, resulting in poor contact of the pole piece and lithium deposition. Lithium deposition will cause the internal temperature of the battery to rise and the internal resistance of the battery to increase, thereby affecting the capacity and discharge performance of the battery device 100.

[0169] Specifically, the electrode assembly includes a pole piece and a pole ear, the pole piece is connected to the pole ear, one end of the electrode lead is connected to the pole ear, and the other end extends out of the outer soft shell. The pole piece is partially squeezed or deformed, which may cause poor contact of the pole piece, thereby generating a poor lithium insertion area and accompanied by lithium precipitation. The current limiting member 40 and the pole piece are misaligned along the first direction to avoid the current limiting member 40 from squeezing the pole piece during the movement of the battery device 100.

[0170] In one embodiment, the battery device 100 is an 80Ah ternary lithium battery with a battery size of 13.8mm×123mm×355mm. According to the new version of the IEC safety standard for power batteries of the International Electrotechnical Commission (IEC) IEC 62660-3, the battery device 100 is subjected to a built-in "L"-shaped foreign body extrusion test, and the results are as follows:

[0171]

[0172] Among them, 4P2S means that the battery device 100 includes two parallel units 20, the two parallel units 20 are connected in series, each parallel unit 20 includes four pouch-shaped battery cells 21, and the four pouch-shaped battery cells 21 are connected in parallel to form three parallel circuits. The four pouch-shaped battery cells 21 in the two parallel units 20 are connected in series in pairs to form four series routes. A current limiting component 40 is provided in each parallel circuit.

[0173] The built-in "L"-shaped foreign body squeeze test is a squeeze test for batteries. The purpose of the test is to evaluate whether the internal foreign body of the battery device 100 will cause product performance degradation, damage or safety hazards when it is subjected to external mechanical pressure. During the test, a sample of the battery device 100 to be tested is prepared, and a simulated "L"-shaped foreign body with a certain hardness and size is placed inside the battery device 100 to simulate the foreign body that may exist in real situations.

[0174] In the squeeze test, a dedicated squeeze test device is used to squeeze the battery or product. The direction and force of the squeeze should be set according to the actual use scenario of the product and the possible stress conditions. During the squeeze process, the voltage, current, temperature and other parameters of the battery or product are continuously monitored, as well as whether there are abnormal sounds, odors or leakage.

[0175] During the test, data such as voltage change, current fluctuation, and temperature change of the battery device 100 are recorded, and the test results are analyzed to evaluate the impact of internal foreign matter on battery or product performance, and finally the above table is obtained.

[0176] In summary, by providing the current limiting element 40 in any parallel circuit of the plurality of pouch-shaped battery cells 21 in a heat-conducting housing 10 , the probability of a large amount of concentrated heat being generated in a short period of time due to an internal short circuit can be reduced.

[0177] According to some embodiments of the present application, the pouch-shaped battery cell 21 is any one of a lithium iron phosphate battery cell, a ternary lithium battery cell, and a solid-state battery cell.

[0178] That is, in some embodiments, the pouch-shaped battery cell 21 is configured as a lithium iron phosphate battery, in some embodiments, the pouch-shaped battery cell 21 is configured as a ternary lithium battery cell, and in some embodiments, the pouch-shaped battery cell 21 is configured as a solid-state battery cell.

[0179] The solid-state battery cell may be, but is not limited to, a polymer solid-state battery cell, an oxide solid-state battery cell, a sulfide solid-state battery cell, a halide solid-state battery cell, etc. The solid-state battery cell may also be a semi-solid-state battery cell or a fully solid-state battery cell.

[0180] In the above technical scheme, in the embodiment of the present application constructed as a lithium iron phosphate battery cell, the reliability of the pouch-shaped battery cell can be improved and the cycle life of the pouch-shaped battery cell can be extended. In the embodiment of the present application constructed as a ternary lithium battery cell, the energy density of the pouch-shaped battery cell can be improved and the cruising range can be improved. In the embodiment of the present application constructed as a solid-state pouch-shaped battery cell, not only the energy density can be improved, but also the reliability can be improved.

[0181] According to some embodiments of the present application, when the pouch-shaped battery cell 21 is a lithium iron phosphate (LiFeO4) battery cell, the ratio of the positive electrode active material, the positive electrode binder and the positive electrode conductive agent in the positive electrode material of the pouch-shaped battery cell 21 is 96: (1-3): (1-3); when the pouch-shaped battery cell 21 is a ternary lithium battery cell, and the ratio of the positive electrode active material, the positive electrode binder and the positive electrode conductive agent in the positive electrode material of the pouch-shaped battery cell 21 is 96: (2-3): (1-2).

[0182] It can be understood that when the pouch-shaped battery cell 21 is a lithium iron phosphate battery cell, in the positive electrode material of the pouch-shaped battery cell 21, the positive electrode active material accounts for 96 parts of the total weight of the positive electrode material, the binder accounts for 1 to 3 parts of the total weight of the positive electrode material (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 conductive agent accounts for 1 to 3 parts of the total weight of the positive electrode material (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.).

[0183] For example, when the pouch-shaped battery cell 21 is a lithium iron phosphate battery cell, the positive electrode active material is LFP (which may refer to LiFePO4, i.e., lithium iron phosphate), the binder may be PVDF (polyvinylidene fluoride), and the conductive agent may be conductive carbon black, wherein LFP:PVDF:conductive carbon black may be 96:2:2, that is, the total weight of the positive electrode active material is 100 parts, LFP accounts for 96 parts, PVDF accounts for 2 parts, and conductive carbon black also accounts for 2 parts. The weight unit of the positive electrode active material may be grams.

[0184] When the pouch-shaped battery cell 21 is a ternary battery cell, in the positive electrode material of the pouch-shaped battery cell 21, the positive electrode active material accounts for 96 parts of the total weight of the positive electrode material, the binder accounts for 2-3 parts of the total weight of the positive electrode material (for example, including but not limited to 2, 2.2, 2.5, 2.8, 3, etc.), and the conductive agent accounts for 1-2 parts of the total weight of the positive electrode material (for example, including but not limited to 1, 1.2, 1.5, 1.8, 2, etc.). Among them, the ternary battery cell can be but not limited to nickel cobalt manganese lithium oxide system, nickel cobalt aluminum lithium oxide system, etc.

[0185] For example, the ternary material of the ternary battery cell can be eight series LiNi 0.8 Co 0.1 Mn 0.1 O2, the weight ratio of the positive electrode active material, binder and conductive agent is 96:2.5:1.5, that is, the total weight of the positive electrode material is divided into 100 parts, eight series LiNi 0.8 Co 0.1 Mn 0.1 O2 accounts for 96 parts, the binder accounts for 2.5 parts, and the conductive agent accounts for 1.5 parts.

[0186] In the above technical solution, when the bag-shaped battery cell 21 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 bag-shaped battery cell 21 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 amount 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.

[0187] In a second aspect, the present application provides an energy storage device 1, which includes a plurality of battery devices 100 in any of the above embodiments, and the battery devices 100 are used to store or provide electrical energy.

[0188] Energy storage devices can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems or temporary power supply systems. Energy storage devices can store electrical energy as needed and output it at the appropriate time. For example, energy storage devices can store electrical energy when electricity consumption is low, and provide electrical energy to relevant users or electrical devices when electricity consumption is high.

[0189] In some embodiments, the energy storage device is an energy storage container or an energy storage cabinet.

[0190] In some embodiments, the energy storage device may include a cabinet and one or more battery clusters, wherein the battery clusters are housed in the cabinet.

[0191] In some embodiments, the energy storage device may include modules such as a thermal management module, a main control module, a master control module, a power distribution module, and a fire protection module.

[0192] As an example, the thermal management module may include a liquid cooling unit that provides cooling liquid for regulating the temperature of the battery cells to each battery device through a pipeline.

[0193] As an example, the main control module can be used as a battery management unit of a battery cluster to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power or temperature of the battery cluster. For example, the charging and discharging current and voltage of the battery cluster can be controlled. The main control module includes a slave battery management unit SBMU (SBMU), a fusion switch and other modules.

[0194] As an example, the master control module can be used as a battery management unit of an energy storage device to monitor and manage the energy storage device. The master control module can monitor information such as the current, voltage, power, state of charge or temperature of the energy storage device. For example, the charging and discharging current, voltage, etc. of the energy storage device can be controlled. As an example, the master control module includes an insulation monitoring module IMM (Insulation Monitoring Module, IMM), a master battery management unit MBMU (Master Battery Management Unit, MBMU), Ethernet ETH (EtherNet, ETH) and a fiber optic conversion module and other modules.

[0195] As an example, the fire protection system includes a control panel, detectors, alarm devices, etc., which are used to detect, alarm or extinguish fire in the energy storage system.

[0196] As an example, the power distribution device may be used to distribute power to the power modules of the energy storage device.

[0197] In a third aspect, the present application provides an energy storage system, which includes a power conversion device 2 and the energy storage device 1 in the above embodiment, wherein the power conversion device 2 is used to electrically connect the power generation device and the energy storage device 1.

[0198] The energy storage system provided in the embodiments of the present application may be any power system that requires an energy storage device.

[0199] In some embodiments, Figure 1 As shown, the energy storage system may include one or more energy storage devices 1 and a power converter 2 (Power Converter System, PCS), and the power converter 2 is used to connect between the power generation equipment 3 and the energy storage device 1. The power generation equipment 3 is used to generate electric energy, and the electric energy generated by the power generation equipment 3 can be stored in the energy storage device 1 through the power converter 2. As an example, the power generation equipment 3 can specifically be a solar panel, a hydropower generation equipment, a thermal power generation equipment, a wind power generation equipment, etc. Among them, the specific type of the power generation equipment 3 is not limited in this application.

[0200] In a fourth aspect, the present application provides an electrical device, which includes the battery device 100 in any of the above embodiments, the energy storage device 1 in the above embodiments, or the energy storage system in the above embodiments, and the battery device 100, the energy storage device 1 or the energy storage system is used to provide electrical energy to the electrical device.

[0201] In a fifth aspect, an embodiment of the present application provides a charging network, which includes a charging pile and an energy storage device in the above embodiment or an energy storage system in the above embodiment, and the energy storage device or the energy storage system is used to provide electrical energy for the charging pile.

[0202] like Figure 2 As shown, it includes a charging pile 4 and an energy storage device 1, the charging pile 4 is electrically connected to the energy storage device 1, and the energy storage device 1 is used to provide electric energy to the charging pile 4. The charging pile 4 is electrically connected to the battery device in the energy storage device 1 through a cable, and the battery device can provide its stored electric energy to the charging pile 4. The charging pile 4 has one or more connectors 5, and the connector 5 is used to connect to an electric device (such as a vehicle), so that the electric device can be replenished with energy.

[0203] The energy storage device can be located inside the charging pile (such as an integrated storage and charging machine) or outside the charging pile.

[0204] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery device, characterized in that: include: a plurality of heat conductive housings; A plurality of parallel units, each of which comprises a plurality of pouch-shaped battery cells connected in parallel, wherein one of the heat-conducting housings correspondingly accommodates a plurality of the pouch-shaped battery cells in one of the parallel units; A parallel circuit is provided between at least two of the pouch-shaped battery cells in the parallel unit; A series unit, wherein the series unit includes the pouch-shaped battery cells connected in series and respectively located in a plurality of the parallel units, and a line between two pouch-shaped battery cells located in different parallel units and connected in series is a series line; A plurality of current limiting components are provided on any of the parallel circuits, and the current limiting components are located outside the series circuits; the current limiting components are used to limit the current size of the corresponding parallel circuits.

2. The battery device according to claim 1, characterized in that: The heat-conducting housing has at least one open end surface, the battery device includes a cold plate, the open end surface faces the cold plate, and the heat-conducting housing is connected to the cold plate, or the pouch-shaped battery cell is connected to the cold plate for heat dissipation.

3. The battery device according to claim 2, characterized in that: A gap is formed between the pouch-shaped battery cell and the cold plate on the side facing the open end surface, and the gap is filled with heat-conducting glue.

4. The battery device according to claim 2, characterized in that: A limiting portion is provided at the end of the open end surface, the limiting portion protrudes from the interior of the heat-conducting housing, and the limiting portion is arranged between the pouch-shaped battery cell and the open end surface.

5. The battery device according to claim 4, characterized in that: The heat-conductive shell includes two open end surfaces, both of which are formed with the limiting parts, and a gap is formed between the pouch-shaped battery cell and the cold plate on the side facing the open end surface, and the gap is filled with thermal conductive adhesive, and the thermal conductive adhesive is at least partially located between the two limiting parts to thermally connect the pouch-shaped battery cell located on one side of the limiting part and the cold plate located on the other side of the limiting part.

6. The battery device according to claim 1, characterized in that: The pouch-shaped battery cell includes an electrode lead, and the battery device includes a first connector, which is connected to the electrode leads of the pouch-shaped battery cells in different parallel units to form the series circuit, and the current limiting component is connected to the electrode leads of different pouch-shaped battery cells in the same parallel unit to form the parallel loop.

7. The battery device according to claim 6, characterized in that: The resistance value of the current limiting component is greater than the resistance value of the first connecting component.

8. The battery device according to claim 6, characterized in that: The first connecting member and the current limiting member are both made of conductive materials, and an insulating layer is provided between the current limiting member and the first connecting member.

9. The battery device according to claim 6, characterized in that: On the same pouch-shaped battery cell, the first connector and the current limiting member are respectively connected to different positions of the same side surface of the electrode lead, or the first connector and the current limiting member are respectively connected to different side surfaces of the electrode lead.

10. The battery device according to claim 1, characterized in that: The resistance of the current limiting component is greater than or equal to 0.2Ω, or the current limiting component is used to limit the current of the parallel circuit to be less than or equal to 20A.

11. The battery device according to claim 10, characterized in that The resistance value of the current limiting element ranges from [0.2Ω, 1000Ω].

12. The battery device according to claim 1, characterized in that: The pouch-shaped battery cell comprises a main body and electrode leads. The main bodies of the plurality of pouch-shaped battery cells in the same heat-conducting housing are arranged side by side along a first direction. The current limiting member is located on one side of the main body along a second direction. The first direction and the second direction are perpendicular to each other.

13. The battery device according to claim 12, characterized in that: The pouch-shaped battery cell comprises an outer soft shell and an electrode assembly, the electrode assembly comprises a pole piece portion and a pole ear portion, and along the first direction, the current limiting component and the pole piece portion are misaligned.

14. The battery device according to any one of claims 1 to 13, characterized in that: The pouch-shaped battery cell is any one of a lithium iron phosphate battery cell, a ternary battery cell, and a solid-state battery cell.

15. An energy storage device, characterized in that: The invention comprises a plurality of battery devices according to any one of claims 1 to 14, wherein the battery devices are used to store or provide electrical energy.

16. An energy storage system, characterized in that: It comprises a power conversion device and the energy storage device as claimed in claim 15, wherein the power conversion device is used to electrically connect a power generation device and the energy storage device.

17. An electrical device, characterized in that: The electrical device includes the battery device according to any one of claims 1 to 14, or the electrical device includes the energy storage device according to claim 15, or the electrical device includes the energy storage system according to claim 16, and the battery device, the energy storage device or the energy storage system is used to store or provide electrical energy.

18. A charging network, characterized in that: It comprises a charging pile and the energy storage device according to claim 15 or the energy storage system according to claim 16, wherein the energy storage device or the energy storage system is used to provide electrical energy for the charging pile.

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