Battery monomer, battery device and electric equipment

Abstract

The utility model discloses a battery monomer, a battery device and electric equipment, and relates to the technical field of batteries, the battery monomer comprises a shell, a winding battery cell and a lamination battery cell, the shell forms a mounting cavity; the thickness direction of the winding battery cell is a first direction; the laminated battery cell and the winding electrode assembly are arranged in the mounting cavity in the first direction, the laminated battery cell comprises a first laminated battery cell, and the first laminated battery cell is located between the winding battery cell and the cavity wall of the mounting cavity. According to the single battery, the cracking risk of the outer ring of the winding battery cell can be reduced.

Description

Technical Field

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

[0002] During the use of the battery, the active layer of the electrode of the battery cell in the battery will expand. Due to the characteristics of the battery's own winding structure, the electrode of the outermost circle of the electrode assembly has a higher risk of cracking, which causes the battery performance to decline and affects the battery life. Utility Model Content

[0003] The main purpose of the utility model is to provide a battery cell, aiming to solve the technical problem that the pole piece in the battery cell is easy to crack.

[0004] To achieve the above-mentioned purpose, the battery cell proposed by the utility model comprises:

[0005] a housing, wherein the housing forms a mounting cavity;

[0006] A wound battery cell, wherein the thickness direction of the wound battery cell is a first direction; and

[0007] A laminated battery core, wherein the laminated battery core and the wound battery core are arranged in the mounting cavity in the first direction;

[0008] The laminated battery core includes a first laminated battery core, and the first laminated battery core is located between the wound battery core and the cavity wall of the installation cavity.

[0009] In the battery cell structure, a wound cell and a laminated cell are provided, and the wound cell can be charged and discharged with the laminated cell without losing energy density. At the same time, the arrangement of the laminated cell can reduce the winding thickness of the wound cell, and can reduce the risk of cracking due to excessive expansion force; the laminated cell includes a first laminated cell located between the wound cell and the cavity wall of the installation cavity, which can isolate at least part of the wound cell from the shell, avoid direct contact between the tangent point and the shell after the pole piece expands, reduce the risk of fracture caused by friction, and improve the performance stability of the battery cell.

[0010] In one embodiment of the present invention, two first laminated battery cells are provided, and the two first laminated battery cells are respectively located on both sides of the wound battery cell in the thickness direction.

[0011] The battery cell of this structure can further reduce the number of winding turns of the wound battery cell and isolate the wound battery cell from the shell, thereby reducing the risk of cracking caused by expansion force and friction.

[0012] In an embodiment of the present invention, two wound battery cells are provided, and the two wound battery cells and the first stacked battery cell are arranged in the installation cavity in a first direction.

[0013] The provision of two wound battery cells can share the winding thickness of one wound battery cell, further reducing the risk of cracking caused by excessive expansion force.

[0014] In one embodiment of the present invention, the laminated battery core further includes a second laminated battery core, and the second laminated battery core is located between the two wound battery cores.

[0015] The battery cell of this structure can reduce the risk of cracking caused by the expansion friction between the two wound battery cells.

[0016] In an embodiment of the present invention, the tail end of the pole piece of the outermost circle of each of the wound battery cells faces the cavity wall of the installation cavity.

[0017] In this example, the end position of the wound battery cell is set close to the shell, which can reduce the tension effect and thus reduce the risk of outer ring breakage.

[0018] In one embodiment of the present invention, two first stacked battery cells are provided, and each first stacked battery cell is disposed between one of the wound battery cells and the cavity wall of the installation cavity.

[0019] By locating the two stacked battery cells on the outside of the two wound battery cells, the cutting point where the fracture occurs can be further moved inward, avoiding direct contact between the cutting point and the shell after the pole piece expands, thereby reducing the risk of fracture of the outer ring pole piece of the wound battery cell.

[0020] In one embodiment of the present utility model, the wound battery core comprises a first straight portion and two curved portions, two ends of the first straight portion are connected to the two curved portions, and the length of the pole piece of the first laminated battery core is the same as the length of the first straight portion;

[0021] Alternatively, the wound battery cell comprises a first straight portion and two curved portions, two ends of the first straight portion are connected to the two curved portions, and the length of the pole piece of the first laminated battery cell is the same as the length of a line connecting the two end surfaces of the two curved portions.

[0022] The length of the pole piece of the first stacked battery cell is the same as the length of the first straight portion. During the battery cell expansion process, only part of the structure of the curved portion of the wound battery cell expands, thereby reducing the tension effect of the expansion there and reducing the risk of fracture at the tangent point of the curved portion of the wound battery cell.

[0023] When the length of the pole piece of the first stacked battery cell is the same as the overall length of the wound battery cell, the tangent point of the curved portion of the wound battery cell can be effectively wrapped to reduce the risk of fracture at the tangent point.

[0024] In one embodiment of the present utility model, the wound battery core includes a first straight portion and two curved portions, and two ends of the first straight portion are connected to the two curved portions;

[0025] The first laminated battery core includes a second straight portion and surrounding portions connected to two ends of the second straight portion, the second straight portion corresponds to the first straight portion, and the surrounding portion is arranged around at least a portion of the outer side surface of the curved portion.

[0026] The first stacked battery cell of this example can further increase the area of ​​the wrapped curved portion, increase the continuity between the two battery cells, and allow the pole piece to completely release lithium.

[0027] In one embodiment of the utility model, a second straight portion is respectively provided on opposite sides of the first straight portion of the wound battery cell, and two surrounding portions are correspondingly provided around a curved portion of the wound battery cell, and the free ends of the two surrounding portions are opposite and spaced apart.

[0028] The two first stacked battery cells of this structure are similar in shape to the wound battery cells, and the two surrounding parts are disconnected in the middle of the bent part, which can release the tension at the corners of the surrounding parts, thereby avoiding the outer ring of the pole piece from breaking due to expansion force.

[0029] In one embodiment of the present invention, the number of winding layers of the wound battery cell is n, and the number of stacking layers of the first laminated battery cell is m, wherein the ratio of m to n is greater than or equal to 1:50 and less than or equal to 5:1.

[0030] The battery cells of this structure can meet the processing technology and effectively reduce the risk of breakage of the outer ring of the wound battery cell.

[0031] In one embodiment of the present invention, the portion of the outermost circle of the wound battery core facing the cavity wall of the installation cavity is a first single-sided coating structure.

[0032] The pole piece on the side of the wound battery cell closest to the shell is set as the first single-sided coating structure, which can meet the requirements of lithium insertion and extraction, while reducing the use of active layer materials and reducing costs.

[0033] In one embodiment of the present invention, a portion of the first stacked battery core closest to the cavity wall of the mounting cavity is a second single-sided coating structure.

[0034] The pole piece on the side of the first stacked battery cell closest to the shell is set as the second single-sided coating structure, which can meet the requirements of lithium insertion and extraction, while reducing the use of active layer materials and reducing costs.

[0035] In one embodiment of the present utility model, the wound battery cell comprises a first anode electrode sheet and a first cathode electrode sheet wound around each other, and a first isolation film disposed between the first cathode electrode sheet and the first anode electrode sheet;

[0036] The first laminated battery cell comprises a second anode electrode sheet and a second cathode electrode sheet which are alternately and stacked, and a second isolation film which is arranged between the second cathode electrode sheet and the second anode electrode sheet;

[0037] The pole piece at the outermost circle of the wound battery cell is the first anode pole piece, and the pole piece of the first stacked battery cell close to the wound battery cell is the second cathode pole piece.

[0038] The battery cells of this structure can increase energy density and improve performance.

[0039] The utility model also provides a battery device, which includes any battery cell as described above.

[0040] Protection of the second subject.

[0041] The utility model also provides an electrical device, comprising the battery device as described above.

[0042] Protection of the third subject. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0044] Figure 1 It is a structural schematic diagram of the electric equipment of the utility model;

[0045] Figure 2 It is a partial exploded view of the battery device of the utility model;

[0046] Figure 3 It is a partial structural schematic diagram of the first embodiment of the battery cell of the utility model;

[0047] Figure 4 It is a partial structural schematic diagram of the second embodiment of the battery cell of the utility model;

[0048] Figure 5 It is a partial structural schematic diagram of the third embodiment of the battery cell of the utility model;

[0049] Figure 6 It is a partial structural schematic diagram of the fourth embodiment of the battery cell of the utility model;

[0050] Figure 7 This is a partial structural schematic diagram of the fifth embodiment of the battery cell of the utility model;

[0051] Figure 8 This is a schematic structural diagram of a sixth embodiment of a battery cell of the utility model;

[0052] Fig. 9 This is a schematic structural diagram of the seventh embodiment of the battery cell of the utility model;

[0053] Fig.10 This is a schematic structural diagram of an eighth embodiment of a battery cell of the utility model;

[0054] Fig.11 It is a structural schematic diagram of a ninth embodiment of a battery cell of the present utility model.

[0055] Description of Figure Numbers:

[0056] 100. Battery device; 10. Case; 11. First part; 12. Second part; 20. Battery cell; 21. Shell; 21a. Mounting cavity; 22. Winding battery cell; 22a. First straight portion; 22b. Bent portion; 2211. First single-sided coating structure; 23. Laminated battery cell; 23a. Second straight portion; 23b. Surrounding portion; 231. First laminated battery cell; 2311. Second single-sided coating structure; 232. Second laminated battery cell; 200. Controller; 300. Motor.

[0057] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0059] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0060] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" 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, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0061] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text is to include three parallel solutions. Taking "A and / or B as an example", it includes solution A, or solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0062] The battery devices mentioned in the art can be divided into disposable batteries and rechargeable batteries according to whether they are rechargeable. The common types of rechargeable batteries currently include: lead-acid batteries, nickel-metal hydride batteries and lithium-ion batteries. The battery device described in the embodiment of the present utility model refers to a rechargeable battery. The following will mainly describe the embodiments disclosed in the present utility model by taking lithium-ion batteries as an example. It should be understood that the embodiments disclosed in the present utility model are applicable to any other appropriate type of rechargeable batteries. The battery device mentioned in the embodiments disclosed in the present utility model can be directly or indirectly applied to appropriate equipment to power the equipment.

[0063] The battery device mentioned in the embodiments disclosed in the present utility model refers to a single physical module including one or more battery cells to provide a predetermined voltage and capacity, which can be a battery module or a battery pack. The battery cell is the basic unit in the battery device, which can be used to make a battery module or a battery pack. The battery module is formed by connecting a certain number of battery cells in series and / or in parallel and placing them in a frame in order to protect the battery cells from external impact, heat, vibration, etc. The battery pack generally includes a battery module, a battery management system, and a box that accommodates the battery module and the battery management system. The battery management system is used to monitor and manage the charging and discharging process of the battery module.

[0064] The battery cell is an important component of the battery monomer. According to the preparation method of the battery cell, it can be divided into a wound battery cell and a laminated battery cell. Among them, the wound battery cell is widely used because it is relatively simple to operate and the quality is easy to control. The wound battery cell generally includes a negative electrode sheet, a positive electrode sheet and a separator arranged and wound in a preset order. The positive electrode sheet and the negative electrode sheet are generally composed of a current collector and an active material layer coated on the current collector, respectively. The wound battery cell can be a square structure or a cylindrical structure. Among them, the square wound battery cell is widely used due to its advantages such as good heat dissipation.

[0065] As the temperature of the battery cell increases during use, the active material layer on each pole piece in the wound battery cell will expand due to the temperature increase, and then exert an outward expansion force on the corresponding part wrapped outside it, such as the pole piece located in the outer ring. In addition, as the expansion continues, the outer wall of the pole piece in the battery cell will contact and squeeze the inner wall of the shell (for ease of description, this phenomenon is referred to as the top shell below), so that the pole piece will receive the pressure applied to it by the shell, and at the same time, the pole piece located in the outer ring of the battery cell will also come into frictional contact with the shell during the expansion process, thereby receiving friction from the shell.

[0066] At this time, due to the characteristics of the winding structure of the square wound electrode assembly, the electrode pieces located on the outer circle will be subject to outward pressure exerted by the inner circle electrode pieces due to the expansion of the active material layer. After the top shell of the electrode assembly, the electrode pieces located on the outer circle will also be subject to the friction force exerted on them by the outer shell, which will cause stress concentration in the several circles of electrode pieces close to the shell, and are very prone to cracking. In particular, the risk of cracking of the outermost positive and negative electrode pieces is relatively high, which will cause the battery performance to decline, and may even puncture the diaphragm and cause the battery short circuit and other risks, affecting the battery life.

[0067] Based on the above background, the utility model proposes a battery cell. By improving the battery cell, a wound battery cell and a stacked battery cell are combined and arranged together in a shell, the winding thickness of the wound battery cell can be reduced, and the contact between part of the outer ring electrode of the wound battery cell and the shell can be isolated, thereby reducing the risk of cracking caused by expansion force and friction.

[0068] The battery device disclosed in the embodiment of the present application can be used in various energy storage systems that use batteries as power sources or use batteries as energy storage elements. The electrical equipment can be, but is not limited to, mobile phones, tablets, laptops, electric toys, electric tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0069] For the convenience of explanation, the following examples are referred to Figure 1, an electrical device in one embodiment of the present application is taken as an example of a vehicle.

[0070] Figure 1 The electrical equipment provided for some embodiments of the present application is a schematic diagram of the structure of a vehicle. The vehicle 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, and the battery device 100 may be provided at the bottom, head or tail of the vehicle. The battery device 100 may be used to power the vehicle, for example, the battery device 100 may be used as an operating power source for the vehicle. The vehicle 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.

[0071] In some embodiments of the present application, the battery device 100 can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0072] refer to Figure 2 , Figure 2 An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box 10 and at least two battery cells 20, wherein the box 10 is used to provide a storage space for the battery cells 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space. The second part 12 may be a hollow structure with one end open, the first part 11 may be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0073] In the battery device 100, there may be a plurality of battery cells 20, which may be connected in series, in parallel, or in mixed series to form a whole and accommodated in the box 10. Mixed series means that the plurality of battery cells 20 are both connected in series and in parallel. The battery device 100 may also include other structures, for example, a busbar component for realizing electrical connection between the plurality of battery cells 20.

[0074] The battery cell 20 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, etc. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0075] In some cases, the battery cell 20 can also be directly installed in the vehicle without the box body 10 , that is, there is no need to form a battery pack, and the structure of the vehicle body itself serves as a fixing structure for the battery cell 20 .

[0076] The battery cell 20 of the present application is introduced below with a specific embodiment:

[0077] Please refer to Figure 3 and Figure 4 In one embodiment of the present invention, the battery cell 20 includes:

[0078] A housing 21, wherein the housing 21 forms a mounting cavity 21a;

[0079] A wound battery cell 22, wherein the thickness direction of the wound battery cell 22 is a first direction; and

[0080] The laminated battery core 23 and the wound electrode assembly are arranged in the first direction in the mounting cavity 21a; the laminated battery core 23 includes a first laminated battery core 231, and the first laminated battery core 231 is located between the wound battery core 22 and the cavity wall of the mounting cavity 21a.

[0081] In this embodiment, the battery cell 20 includes a shell 21, which is a closed structure and forms a mounting cavity 21a required for the battery cell. The shell 21 generally includes an end cover and a shell body. The shell body forms a receiving groove with an opening. The battery cell is installed in the receiving groove, and the end cover covers the opening to form the mounting cavity 21a. The specific structure of the end cover and other functional components arranged thereon can refer to the existing end cover structure, and will not be described in detail here. Of course, electrolyte and other components are also arranged in the shell 21, which will not be described in detail here.

[0082] A battery cell 20 may have one, two or more cells. Here, at least two cells are included, one of which is a wound cell 22. The wound cell 22 is formed by winding pole pieces, specifically including anode pole pieces and cathode pole pieces. Generally, the order of anode pole piece, separator, cathode pole piece, separator, or cathode pole piece, separator, anode pole piece, separator is stacked and wound in sequence to form a flat multi-turn winding body. The flat part of the wound cell 22, that is, the plane part, is the large surface, and the bent and wound part of the wound cell 22 is the corner.

[0083] The other is a laminated battery cell 23, which is formed by stacking a plurality of pole pieces, specifically including anode pole pieces and cathode pole pieces. In one example, the number of anode pole pieces and cathode pole pieces in the laminated battery cell 23 is the same, and in another example, the number of anode pole pieces and cathode pole pieces in the laminated battery cell 23 may also be different. The thickness direction of the wound battery cell 22 is the first direction, and the stacking direction of the laminated battery cell 23 is also the first direction, so the wound battery cell 22 and the laminated battery cell 23 are stacked in the thickness direction of the wound battery cell 22, that is, the laminated battery cell 23 is in contact with the large surface of the wound battery cell 22, and the pole piece close to the wound battery cell 22 may have the opposite polarity to the pole piece of the wound battery cell 22 or be isolated by a diaphragm. The laminated cell 23 and the wound cell 22 can be electrically connected. For example, the anode electrode sheet in the wound cell 22 is electrically connected to the anode electrode sheet in the laminated cell 23 by means of tab welding, and the cathode electrode sheet in the wound cell 22 is electrically connected to the cathode electrode sheet in the laminated cell 23 by means of tab welding. Specifically, the laminated cell 23 includes a first laminated cell 231, which is located between the wound cell 22 and the cavity wall of the mounting cavity 21a.

[0084] In the structure of the battery cell 20, a wound cell 22 and a laminated cell 23 are provided. The wound cell 22 can be charged and discharged with the laminated cell 23 without losing energy density, and the laminated cell 23 can have higher energy density and capacity density. At the same time, the winding thickness of the wound cell 22 can be reduced by the provision of the laminated cell 23, which can reduce the risk of cracking due to excessive expansion force; since the wound cell 22 is most likely to break due to friction with the inner wall of the shell 21 after expansion, the laminated cell 23 includes a first laminated cell 231, which can isolate at least part of the wound cell 22 from the shell 21, avoid direct contact between the tangent point and the shell 21 after the pole piece expands, reduce the risk of breakage caused by friction, so as to improve the performance stability of the battery cell 20 and extend the service life.

[0085] Please refer to Figures 5 to 7 In one embodiment of the present invention, two first laminated battery cells 231 are provided, and the two first laminated battery cells 231 are respectively located on both sides of the wound battery cell 22 in the thickness direction.

[0086] In this example, two first laminated cells 231 are provided, which can further improve the energy density of the battery cell 20 and reduce the number of windings of the wound cell 22. At the same time, the two first laminated cells 231 are respectively located on both sides of the wound cell 22 in the thickness direction, that is, the two large surfaces of the wound cell 22 are isolated from the shell 21 by the first laminated cells 231, and the corners of the wound cell 22 are spaced from the shell 21.

[0087] The battery cell 20 of this structure can further reduce the number of windings of the wound battery cell 22 and isolate the wound battery cell 22 from the shell 21, thereby further reducing the friction force on the corner pole piece and further reducing the risk of cracking caused by expansion force and friction.

[0088] Please refer to Figure 8 In one embodiment of the present invention, two wound battery cells 22 are provided, and the two wound battery cells 22 and the first stacked battery cell 231 are arranged in the first direction in the installation cavity 21a.

[0089] In this example, the provision of two wound battery cells 22 can share the winding thickness of one wound battery cell 22, further reducing the risk of cracking caused by excessive expansion force.

[0090] The two wound cells 22 and the first laminated cell 231 are arranged in the first direction, and the two wound cells 22 are attached to each other with large surfaces. In one example, the first laminated cell 231 is located between one of the wound cells 22 and the housing 21. In other examples, the first laminated cell 231 is located between the other wound cell 22 and the housing 21.

[0091] In an embodiment of the present invention, the laminated battery core 23 further includes a second laminated battery core 232 , and the second laminated battery core 232 is located between the two wound battery cores 22 .

[0092] In the battery cell 20 of this structure, the second laminated battery cell 232 can separate the large surfaces of the two wound battery cells 22, so that a gap is set at the corner intersection of the two wound battery cells 22, which can reduce the risk of cracking caused by the expansion friction between the two wound battery cells 22.

[0093] Please continue to refer to Figure 8 In one embodiment of the present invention, the tail end of the outermost pole piece of each wound battery cell 22 faces the cavity wall of the installation cavity 21a.

[0094] In this example, when the second stacked battery cell 232 is located between two wound battery cells 22, when only one first stacked battery cell 231 is provided, one of the wound battery cells 22 is disposed close to the housing 21. It should be noted that the pole piece of the outermost circle of the wound battery cell 22 refers to the outermost circle of pole piece structure after the battery cell is wound, that is, the pole piece portion that is not wrapped inside and exposed. The tail end of the pole piece of the outermost circle is the free end of the pole piece of the outermost circle, and the length of the tail end can be consistent with the overall length of the wound battery cell 22, or it can be a part of the length of the wound battery cell 22, which is not limited here. The tail end of the pole piece of the outermost circle faces the cavity wall of the mounting cavity 21a, which can be the cavity wall of the mounting cavity 21a located in the first direction.

[0095] The tail end of the outermost circle of the wound battery cell 22 is arranged close to the shell 21, which can reduce the tension effect and thus reduce the risk of outer circle breakage.

[0096] Please refer to Figure 8 In one embodiment of the present invention, two first stacked battery cells 231 are provided, and each first stacked battery cell 231 is disposed between one of the wound battery cells 22 and the cavity wall of the mounting cavity 21 a.

[0097] In this example, two first laminated cells 231 are provided, which can further improve the energy density of the battery cell 20 and reduce the number of windings of the wound cell 22. At the same time, the two first laminated cells 231 are respectively located on both sides of the wound cell 22 in the thickness direction, that is, the two large surfaces of the wound cell 22 are isolated from the shell 21 by the first laminated cells 231, and the corners of the wound cell 22 are spaced from the shell 21.

[0098] By locating the two first stacked battery cells 231 on the outside of the two wound battery cells 22, the tangent point where the fracture occurs can be further moved inward, avoiding direct contact between the tangent point of the corner after the pole piece expands and the shell 21, thereby reducing the risk of the outer ring pole piece of the wound battery cell 22 being fractured.

[0099] Please refer to Fig. 9 In one embodiment of the present invention, at least one second laminated battery cell 232 is located between two of the wound battery cells 22, and each of at least two first laminated battery cells 231 is disposed between one of the wound battery cells 22 and the cavity wall of the mounting cavity 21a.

[0100] In this example, at least one of the second laminated cells 232 can separate the large surfaces of the two wound cells 22, so that a gap is set at the corner tangent point of the two wound cells 22. At the same time, at least two first laminated cells 231 are respectively located between one side of a wound cell 22 in the thickness direction and the shell 21, that is, the two large surfaces of the wound cell 22 are isolated from the shell 21 by the first laminated cells 231, and a gap is set between the corner of the wound cell 22 and the shell 21.

[0101] The winding thickness of the wound battery cell 22 of this structure can be further reduced, thereby reducing the risk of expansion friction cracking between each wound battery cell 22 and the shell 21 and between two wound battery cells 22 .

[0102] Optionally, two or three second laminated battery cells 232 are located between two wound battery cells 22 , and each of the two first laminated battery cells 231 is disposed between a wound battery cell 22 and a cavity wall of the mounting cavity 21 a .

[0103] Please combine Fig. 9 and Fig.10In one embodiment of the utility model, the wound battery core 22 includes a first straight portion 22a and two curved portions 22b, the two ends of the first straight portion 22a are connected to the two curved portions 22b, and the length of the pole piece of the first laminated battery core 231 is the same as the length of the first straight portion 22a;

[0104] Alternatively, the wound battery cell 22 includes a first straight portion 22a and two curved portions 22b, the two ends of the first straight portion 22a are connected to the two curved portions 22b, and the length of the pole piece of the first laminated battery cell 231 is the same as the length of the line connecting the two end surfaces of the two curved portions 22b.

[0105] The first straight portion 22a in the wound battery cell 22 is a large surface structure, and the curved portion 22b is a corner structure. The first straight portion 22a is formed by the straight portions of a plurality of pole pieces, and the curved portion 22b is formed by the curved portions of a plurality of pole pieces.

[0106] The length of the pole piece of the first laminated battery cell 231 refers to the dimension perpendicular to the first direction on the winding plane, and the length of the first straight portion 22a refers to the dimension perpendicular to the first direction on the winding plane. The line connecting the two end surfaces of the two curved portions 22b refers to the line connecting the two vertices of the two curved portions 22b, and the line connecting the two vertices is the maximum length of the wound battery cell 22.

[0107] In one example, the length of the pole piece of the first stacked battery cell 231 is the same as the length of the first straight portion 22a. During the battery cell expansion process, only a partial structure of the curved portion 22b of the wound battery cell 22 expands, thereby reducing the tension effect of the expansion there and reducing the risk of tangent point fracture of the curved portion 22b of the wound battery cell 22.

[0108] As another example, when the pole piece length of the first stacked battery cell 231 is the same as the maximum length of the wound battery cell 22 , the tangent point of the bent portion 22 b of the wound battery cell 22 can be effectively wrapped to reduce the risk of fracture at the tangent point.

[0109] Of course, when the second laminated battery core 232 is provided, the length of the pole piece of the second laminated battery core 232 may be the same as the length of the first straight portion 22a, or may be the same as the length of the line connecting the two end surfaces of the two curved portions 22b.

[0110] Please refer to Fig.11 In one embodiment of the present utility model, the wound battery core 22 includes a first straight portion 22a and two curved portions 22b, and two ends of the first straight portion 22a are connected to the two curved portions 22b;

[0111] The first laminated cell 231 includes a second straight portion 23a and surrounding portions 23b connected to two ends of the second straight portion 23a, the second straight portion 23a corresponds to the first straight portion 22a, and the surrounding portion 23b is disposed around at least a portion of the outer side surface of the curved portion 22b.

[0112] In this example, the first straight portion 22a is a large surface structure of the wound battery cell 22, and the curved portion 22b is a corner structure of the wound battery cell 22. The second straight portion 23a is arranged in parallel with the first straight portion 22a and has the same length, and the surrounding portion 23b is arranged around at least part of the outer circumference of the curved portion 22b, which means that the surrounding portion 23b is arranged around a part of the curved portion 22b in its extension direction, or the surrounding portion 23b surrounds the entire curved portion 22b, which is not limited here. The surrounding portion 23b can have the same curvature as the curved portion 22b and a different diameter; or it can also be set to have a different curvature and a different diameter.

[0113] The first stacked battery cell 231 of this example can further increase the area of ​​the wrapped curved portion 22b, increase the continuity between the two battery cells, and allow the pole piece to completely release lithium.

[0114] When the second laminated battery core 232 is provided, the structure of the second laminated battery core 232 may also be arranged to be the same as the structure of the first laminated battery core 231 , that is, the second laminated battery core 232 may also include a second straight portion 23 a and a surrounding portion 23 b .

[0115] Please continue to refer to Fig.11 In one embodiment of the utility model, a second straight portion 23a is provided on opposite sides of the first straight portion 22a of the wound battery cell 22, and two surrounding portions 23b are correspondingly provided on a curved portion 22b of the wound battery cell 22, and the free ends of the two surrounding portions 23b are opposite and spaced apart.

[0116] In this example, the wound cell 22 can be the first one, and each wound cell 22 is provided with a laminated cell 23 on both sides in the thickness direction. Then, the first laminated cell 231 is provided on both sides of the wound cell 22, and each surrounding portion 23b only corresponds to half of the arc length of the curved portion 22b. Then, the two surrounding portions 23b located on both sides of the wound cell 22 are together surrounded by the outer peripheral side of the curved portion 22b, and the two surrounding portions 23b are arranged at intervals. The laminated cell 23 of this structure can continue to wind the pole piece after processing the wound cell 22, and then cut the subsequent pole piece corresponding to the middle part of the curved portion 22b, thereby releasing the tension of the outer ring of the laminated cell 23 to form a free end of the surrounding portion 23b. There can be two or more wound battery cells 22. In this case, the laminated battery cells 23 arranged on the opposite sides of each wound battery cell 22 are respectively a first laminated battery cell 231 and a second laminated battery cell 232. The first laminated battery cell 231 and the second laminated battery cell 232 are both provided with a second straight portion 23a and two surrounding portions 23b connecting the second straight portion 23a. The laminated battery cells 23 of this structure are also processed in the same manner as described above.

[0117] The two stacked cells 23 of this structure are similar in shape to the wound cell 22. The two surrounding portions 23b are disconnected in the middle of the curved portion 22b, which can release the tension at the corner of the surrounding portion 23b, thereby preventing the outer ring of the pole piece from breaking due to expansion force. At the same time, the setting of the surrounding portion 23b can increase the area for lithium insertion and extraction from the wound cell 22, further improving the energy density.

[0118] In other examples, the two surrounding portions 23b located on both sides of the curved portion 22b may also respectively surround the curved portion 22b, that is, the projections of the two surrounding portions 23b on the curved portion 22b at least partially overlap.

[0119] In an embodiment of the present invention, the number of winding layers of the wound battery cell 22 is n, and the number of stacking layers of the first laminated battery cell 231 is m, wherein the ratio of m to n is greater than or equal to 1:50 and less than or equal to 5:1.

[0120] The wound battery cell 22 has the advantage of high manufacturing efficiency, so the number of winding layers of the wound battery cell 22 should not be too small, and the number of winding layers of the wound battery cell 22 should not be too large, otherwise the outer ring will be subjected to excessive force during expansion. The laminated battery cell 23 has the advantage of high capacity density, so the number of stacking layers of the first laminated battery cell 231 should not be too large or too small. Therefore, in this example, the ratio of m to n is set to be greater than or equal to 1:50, and less than or equal to 5:1. For example, the number of winding turns of the wound battery cell 22 is 10 to 50 turns, and the number of layers of the wound battery cell 22 is 20 to 100 layers, where m / n can be 1 / 35, 1 / 25, 1 / 10, 1 / 5, 1, 2, 3 or 4, etc. Optionally, the ratio of m to n is set to 1, that is, the number of winding layers of the wound battery cell 22 and the number of stacking layers of the first laminated battery cell 231 are the same.

[0121] The battery cell 20 of this structure can meet the processing technology, that is, improve the production efficiency, and effectively reduce the risk of the outer ring of the wound battery cell 22 breaking.

[0122] In an embodiment of the present invention, the outermost circle of the wound battery core 22 facing the cavity wall of the installation cavity 21 a is the first single-sided coating structure 2211 .

[0123] In this example, when there is one first stacked cell 231, the wound cell 22 directly faces the cavity wall of the mounting cavity 21a. The portion of the outermost pole piece facing the cavity wall of the mounting cavity 21a refers to the tail end of the outermost pole piece, which is arranged facing the cavity wall in the thickness direction of the wound cell 22. The first single-sided coating structure 2211 refers to a pole piece structure in which an active layer material is coated only on one surface of the current collector, and the surface coated with the active layer material is the surface away from the cavity wall of the mounting cavity 21a, so that lithium can be deintercalated with the inner pole piece.

[0124] The portion of the wound battery cell 22 closest to the shell 21 is set as the first single-sided coating structure 2211, which can meet the requirements of lithium insertion and extraction, while reducing the use of active layer materials and reducing costs.

[0125] In an embodiment of the present invention, the portion of the first stacked battery core 231 that is closest to the cavity wall of the mounting cavity 21 a is the second single-sided coating structure 2311 .

[0126] In this example, the first stacked cell 231 is located between the wound cell 22 and the housing 21. The pole piece in the first stacked cell 231 that is away from the wound cell 22 refers to the pole piece that is closest to the cavity wall of the mounting cavity 21a, and the pole piece is arranged opposite to the cavity wall of the mounting cavity 21a. The second single-sided coating structure 2311 refers to a pole piece structure in which an active layer material is coated on only one surface of the current collector in the pole piece, and the surface coated with the active layer material is the surface away from the cavity wall of the mounting cavity 21a, so that lithium can be deintercalated with the inner pole piece.

[0127] The portion of the first stacked battery core 231 closest to the shell 21 is set as the second single-sided coating structure 2311, which can meet the requirements of lithium insertion and extraction, while reducing the use of active layer materials and reducing costs.

[0128] In one embodiment of the present utility model, the wound battery cell 22 includes a first anode electrode sheet and a first cathode electrode sheet wound around each other, and a first isolation film disposed between the first cathode electrode sheet and the first anode electrode sheet;

[0129] The first laminated battery cell 231 includes a second anode electrode sheet and a second cathode electrode sheet that are alternately and stacked, and a second isolation film disposed between the second cathode electrode sheet and the second anode electrode sheet;

[0130] The pole piece at the outermost circle of the wound battery cell 22 is the first anode pole piece, and the pole piece of the first stacked battery cell 231 close to the wound battery cell 22 is the second cathode pole piece.

[0131] In this example, the winding method of the wound battery cell 22 is set to first wind the first separator, then wind the first anode electrode sheet, first enter 1 / 4~1 / 2 circle, and finally wind the first cathode electrode sheet with the first anode electrode sheet to form a winding method of first separator-first anode electrode sheet-first separator-first cathode electrode sheet-first separator. Then, the rolled battery cell is subjected to a hot pressing process, and the outermost first anode electrode sheet is terminated at the corner.

[0132] The first stacked cell 231 is processed by stacking the second separator-the second anode electrode piece-the second separator-the second cathode electrode piece-the second separator in sequence, and then forming a stacked structure of a certain thickness by cold pressing and hot pressing. The electrode piece of the first stacked cell 231 close to the wound cell 22 is set as the second cathode electrode piece, so that lithium can be released between the wound cell 22 and the first stacked cell 231.

[0133] Finally, the first stacked battery cell 231 is arranged on one side of the wound battery cell 22, the copper pole ear of the wound battery cell 22 and the copper pole ear of the first stacked battery cell 231 are connected and fixed, and the aluminum pole ear of the wound battery cell 22 and the aluminum pole ear of the first stacked battery cell 231 are connected and fixed to form an integral battery cell structure.

[0134] The battery cell 20 with this structure can increase the energy density, and the structure in which the first anode electrode sheet wraps the first cathode electrode sheet can improve the performance of the battery cell 20 .

[0135] The present invention also provides a battery device 100, which includes any of the above-mentioned battery cells 20. The battery cell 20 of the battery device 100 adopts all the technical solutions of all the above-mentioned embodiments, and thus has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0136] The battery device 100 may be a battery module or a battery pack.

[0137] The utility model also provides an electric device, including the battery device 100 described above. The battery device 100 of the electric device adopts all the technical solutions of all the above embodiments, and thus has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0138] The power-consuming device may be a mobile phone, a laptop computer, a battery car, an electric car, an energy storage station, etc. The present application does not limit the specific type of the power-consuming device. When the power-consuming device includes the battery device 100, the battery device 100 may provide power.

[0139] The above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the utility model.

Claims

1. A battery cell, characterized in that: The battery cell comprises: a housing, wherein the housing forms a mounting cavity; A wound battery cell, wherein the thickness direction of the wound battery cell is a first direction; and A laminated battery core, wherein the laminated battery core and the wound battery core are arranged in the mounting cavity in the first direction; The laminated battery core includes a first laminated battery core, and the first laminated battery core is located between the wound battery core and the cavity wall of the installation cavity.

2. The battery cell according to claim 1, characterized in that: There are two first laminated battery cores, and the two first laminated battery cores are respectively located on both sides of the wound battery core in the first direction.

3. The battery cell according to claim 1, characterized in that: Two wound battery cells are provided, and the two wound battery cells and the first laminated battery cell are arranged in the first direction in the installation cavity.

4. The battery cell according to claim 3, characterized in that: The laminated battery core also includes a second laminated battery core, and the second laminated battery core is located between the two wound battery cores.

5. The battery cell according to claim 4, characterized in that: The tail end of the pole piece of the outermost circle of each wound battery cell faces the cavity wall of the installation cavity.

6. The battery cell according to claim 3, characterized in that: Two first laminated battery cores are provided, and each first laminated battery core is arranged between one of the wound battery cores and the cavity wall of the installation cavity.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The wound battery core comprises a first straight portion and two curved portions, two ends of the first straight portion are connected to the two curved portions, and the length of the pole piece of the first laminated battery core is the same as the length of the first straight portion; Alternatively, the wound battery cell comprises a first straight portion and two curved portions, two ends of the first straight portion are connected to the two curved portions, and the length of the pole piece of the first laminated battery cell is the same as the length of a line connecting the two end surfaces of the two curved portions.

8. The battery cell according to any one of claims 1 to 6, characterized in that: The wound battery core comprises a first straight portion and two curved portions, and two ends of the first straight portion are connected to the two curved portions; The first laminated battery core includes a second straight portion and surrounding portions connected to two ends of the second straight portion, the second straight portion corresponds to the first straight portion, and the surrounding portion is arranged around at least a portion of the outer side surface of the curved portion.

9. The battery cell according to claim 8, characterized in that: A second straight portion is respectively provided on opposite sides of the first straight portion of the wound battery core, and two surrounding portions are correspondingly provided around a curved portion of the wound battery core, and free ends of the two surrounding portions are opposite and spaced apart.

10. The battery cell according to any one of claims 1 to 6, characterized in that: The number of winding layers of the wound battery cell is n, and the number of stacking layers of the first laminated battery cell is m, wherein the ratio of m to n is greater than or equal to 1:50 and less than or equal to 5:

1.

11. The battery cell according to any one of claims 1 to 6, characterized in that: The portion of the outermost circle of the wound battery core facing the cavity wall of the mounting cavity is a first single-sided coating structure.

12. The battery cell according to any one of claims 1 to 6, characterized in that: The portion of the first laminated battery core closest to the cavity wall of the mounting cavity is a second single-sided coating structure.

13. The battery cell according to any one of claims 1 to 6, characterized in that: The wound battery cell comprises a first anode electrode sheet and a first cathode electrode sheet wound around each other, and a first isolation film arranged between the first cathode electrode sheet and the first anode electrode sheet; The first laminated battery cell comprises a second anode electrode sheet and a second cathode electrode sheet which are alternately and stacked, and a second isolation film which is arranged between the second cathode electrode sheet and the second anode electrode sheet; The pole piece at the outermost circle of the wound battery cell is the first anode pole piece, and the pole piece of the first stacked battery cell close to the wound battery cell is the second cathode pole piece.

14. A battery device, characterized in that: The battery device comprises the battery cell according to any one of claims 1 to 13.

15. An electrical equipment, characterized in that: Comprising the battery device as claimed in claim 14.

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