Power battery and vehicle

Abstract

The invention provides a power battery and a vehicle, the power battery comprises a shell, a heating device and a battery cell, the heating device is arranged in the shell, the heating device comprises a middle area and an edge area, the heating device comprises a plurality of resistors, and the plurality of resistors are distributed in the middle area and the edge area; the heating power of the resistor located in the middle area is lower than that of the resistor located in the edge area; the battery cell is arranged in the shell and connected to the heating device. According to the power battery provided by the invention, the heating power of the resistor in the middle region is lower than the heating power of the resistor in the edge region, so that the heating value of the resistor in the middle region is lower than the heating value of the resistor in the edge region, namely, the heating value of the resistor in the edge region is lower; the heating temperature of the battery cells with relatively high temperature in the middle area is lower than the heating temperature of the battery cells with relatively low temperature in the edge area, so that the temperature of the heated battery cells in the middle area can be consistent with or nearly consistent with the temperature of the heated battery cells in the edge area, and the battery cells in the edge area can be heated in a low-temperature environment; and the temperature balance after the power battery is heated is realized.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a power battery and a vehicle. Background Art

[0002] The storage capacity and performance of power batteries in new energy vehicles are greatly affected by temperature. If new energy vehicles are in a low temperature environment, the storage capacity of the power batteries will decrease, which will in turn affect the endurance of new energy vehicles. In order to increase the temperature of the power battery in a low temperature environment, a heating plate is generally provided in the power battery, which can evenly heat each cell in the power battery.

[0003] However, there are multiple battery cells in the power battery, and the temperature of the battery cell in the middle position is higher than the temperature of the battery cell at the edge position. Since the existing heating plate has the same heating effect on the battery cells at various positions, this will cause the battery cells at different positions in the power battery to have different temperatures after heating, and the temperature consistency of various parts of the power battery is poor. Summary of the invention

[0004] The purpose of the present application is to provide a power battery and a vehicle to solve the problem in the above-mentioned prior art that the battery cells at different positions in the power battery have different temperatures after heating.

[0005] In a first aspect, the present application provides a power battery, comprising:

[0006] case;

[0007] A heating device is disposed in the housing, the heating device includes a middle area and an edge area, the heating device includes a plurality of resistors, the plurality of resistors are distributed in the middle area and the edge area, and the heating power of the resistors in the middle area is lower than the heating power of the resistors in the edge area;

[0008] The battery core is arranged in the shell and connected to the heating device.

[0009] In a possible design, the shell includes a bottom plate, the heating device also includes a heating disk, the heating disk is connected to the bottom plate, and the resistor is connected to the heating disk.

[0010] In a possible design, a plurality of positioning grooves are provided on the heating plate, and the resistors are arranged in the positioning grooves.

[0011] In a possible design, the heating device includes a plurality of heating components, each of the heating components includes a heating film and a plurality of resistors, and the plurality of resistors are encapsulated in the heating film.

[0012] In a possible design, the thickness of the heating component is less than or equal to the depth of the positioning groove.

[0013] In a possible design, the positioning groove is a strip groove; the positioning groove includes a first groove and a second groove, the first groove is located in the middle area, and the second groove is located in the edge area; and / or,

[0014] The positioning groove includes a third groove, at least a portion of the third groove is located in the middle area, and at least another portion of the third groove is located in the edge area.

[0015] In a possible design, a plurality of welding parts are provided on a side of the heating plate facing away from the positioning groove, the welding parts protrude from the side of the heating plate facing away from the positioning groove, and the heating plate is welded to the base plate via the welding parts.

[0016] In a possible design, a plurality of convex beams are provided on the bottom plate, and the convex beams are connected to the welding parts by welding.

[0017] In a possible design, along the thickness direction of the power battery, the ratio of the projected area of ​​the middle region to the projected area of ​​the heating device is between 1 / 2 and 2 / 3.

[0018] In a possible design, an insulating plate is further included, and the insulating plate is arranged between the heating device and the battery core.

[0019] In a second aspect, the present application also provides a vehicle, which includes the power battery provided in the first aspect of the present application.

[0020] The technical solution provided by this application can achieve the following beneficial effects:

[0021] The power battery provided in the present application can make the heating power of the resistors in the middle area lower than the heating power of the resistors in the edge area, so that the heating power of the resistors in the middle area can be lower than the heating power of the resistors in the edge area. That is, the heating temperature of the battery cells with relatively high temperatures in the middle area is lower than the heating temperature of the battery cells with relatively low temperatures in the edge area, so that the temperature of the battery cells in the middle area after heating can be consistent or nearly consistent with the temperature of the battery cells in the edge area after heating, so that the temperature balance of the power battery after heating can be achieved in a low temperature environment.

[0022] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 An exploded diagram of a power battery provided in one embodiment of the present application;

[0024] Figure 2 A top view of a heating device in a power battery provided in an embodiment of the present application installed in a housing;

[0025] Figure 3 A schematic diagram of the structure of a heating plate in a heating device provided in an embodiment of the present application;

[0026] Figure 4 A partial cross-sectional view of a heating assembly provided in one embodiment of the present application;

[0027] Figure 5 A partial cross-sectional view of a heating assembly provided in another embodiment of the present application;

[0028] Figure 6 A top view of a heating plate provided in one embodiment of the present application;

[0029] Figure 7 A top view of a heating plate provided in one embodiment of the present application;

[0030] Figure 8 A side view of a heating plate provided in an embodiment of the present application;

[0031] Fig. 9 An exploded view of the heating device and the bottom plate provided in an embodiment of the present application;

[0032] Fig.10 An exploded diagram of a power battery provided in another embodiment of the present application.

[0033] Reference numerals:

[0034] 1- housing;

[0035] 11- bottom plate;

[0036] 111-convex beam;

[0037] 12- upper shell;

[0038] 2- Heating device;

[0039] 21- heating plate;

[0040] 211- positioning groove;

[0041] 211a-first groove;

[0042] 211b - second slot;

[0043] 211c - third slot;

[0044] 212- welding part;

[0045] 22- heating component;

[0046] 221- heating film;

[0047] 222-resistance;

[0048] 2a - middle area;

[0049] 2b - marginal area;

[0050] 3-Battery cell;

[0051] 4-Insulation board;

[0052] X-length direction;

[0053] Y-width direction;

[0054] Z-thickness direction.

[0055] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0057] In the description of this application, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "plurality" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0058] In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present application are described at the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it should also be understood that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0059] Figure 1 An exploded diagram of a power battery provided in one embodiment of the present application, such as Figure 1As shown, the present application provides a power battery, which can be used in a vehicle, such as a new energy vehicle. The power battery includes a housing 1, a heating device 2, and a battery cell 3. The housing 1 has a storage space, which can be used to store the battery cell 3 and the heating device 2. The housing 1 can provide protection for the battery cell 3 and the heating device 2 inside the housing 1.

[0060] The battery cell 3 is the core part of the power battery and plays a vital role in new energy vehicles. It is a key component for storing and releasing electric energy, and directly determines the endurance, safety and overall performance of new energy vehicles. The battery cell 3 stores and releases electric energy through chemical reactions. There can be multiple battery cells 3, and multiple battery cells 3 can be arranged in an array.

[0061] The battery core 3 may be in contact with the heating device 2 , and the heating device 2 may support and heat the battery core 3 .

[0062] It is understandable that during the operation or charging of the car, the battery cell 3 of the power battery will emit heat. Since the power battery has multiple battery cells 3 arranged in an array, the heat dissipation effect of the battery cell 3 in the middle area 2a will be weaker than the heat dissipation effect of the battery cell 3 in the edge area 2b, resulting in heat easily accumulating at the battery cell 3 in the middle area 2a, thereby causing the temperature of the battery cell 3 in the middle area 2a to be higher than the temperature of the battery cell 3 in the edge area 2b. When the car is running or charging in a low temperature environment, the low temperature environment will cause the power battery to store less electricity, affecting the endurance of the car. Therefore, the power battery needs to be heated in a low temperature environment. However, if a soaking plate is used to heat the battery cell 3, the soaking plate will provide uniform and constant heat at each position, that is, the heating effect of each battery cell 3 is uniform and consistent, which leads to the problem that after the battery cell 3 is heated, the temperature of the battery cell 3 in the middle area 2a is still relatively high, and the temperature of the battery cell 3 in the edge area 2b is relatively low, which is not conducive to the balanced control of the power battery temperature.

[0063] In view of this, in this embodiment, Figure 2 A top view of the heating device 2 in the power battery provided in the embodiment of the present application installed in the housing 1, as shown in FIG. Figure 2 As shown, the heating device 2 includes a middle area 2a and an edge area 2b, and the heating device 2 includes a plurality of resistors 222, and the plurality of resistors 222 are distributed in the middle area 2a and the edge area 2b, and the heating power of the resistors 222 located in the middle area 2a is lower than the heating power of the resistors 222 located in the edge area 2b.

[0064] The edge region 2b is a partial region close to the edge of the heating device 2, and the middle region 2a is a region away from the edge of the heating device 2. For example, the edge region 2b may surround the middle region 2a. During the operation or charging of the vehicle, the heat of the battery cells 3 in the middle region 2a will be higher than the heat of the battery cells 3 in the edge region 2b.

[0065] In this embodiment, at least some of the resistors 222 have different heating powers, wherein different heating powers can be achieved by providing resistors 222 of different volumes.

[0066] Among them, the heating power of the resistor 222 with a larger volume is greater than the heating power of the resistor 222 with a smaller volume. Exemplarily, the resistor 222 includes a first resistor and a second resistor, the volume of the first resistor is greater than the volume of the second resistor, so that the heating power of the first resistor is greater than the heating power of the second resistor, the first resistor is arranged in the edge area 2b, and the second resistor is arranged in the middle area 2a. In this embodiment, by making the heating power of the resistor 222 in the middle area 2a lower than the heating power of the resistor 222 located in the edge area 2b, the heat generated by the resistor 222 in the middle area 2a can be lower than the heat generated by the resistor 222 in the edge area 2b, that is, the heating temperature of the battery cell 3 with a relatively high temperature in the middle area 2a is lower than the heating temperature of the battery cell 3 with a relatively low temperature in the edge area 2b, so that the temperature of the battery cell 3 in the middle area 2a after heating can be consistent or nearly consistent with the temperature of the battery cell 3 in the edge area 2b after heating, so that the temperature balance of the power battery after heating can be achieved in a low temperature environment.

[0067] In one embodiment, along the thickness direction Z of the power battery, the ratio of the projected area of ​​the middle region 2a to the projected area of ​​the heating device 2 is between 1 / 2 and 2 / 3. When multiple battery cells 3 are arranged in an array, the heat of the battery cells 3 located in the middle region 2a is dissipated more slowly, and the heat accumulation coverage of the middle region 2a is larger than that of the edge region 2b. Therefore, the resistor 222 with a smaller heating power can be arranged in the middle region 2a with a larger projected area, and the resistor 222 with a larger heating power can be arranged in the edge region 2b with a smaller projected area, so that after the battery cells 3 are heated by the heating device 2, the temperature of each battery cell 3 can be kept or nearly consistent, and the temperature at each position of the power battery can be balanced.

[0068] In one embodiment, if Figure 1 As shown, the housing 1 includes an upper shell 12 and a bottom plate 11 , and the upper shell 12 and the bottom plate 11 can be fixedly connected by connecting members such as bolts to cover components such as the battery cell 3 and the heating device 2 inside. Figure 3 A schematic diagram of the structure of the heating plate 21 in the heating device 2 provided in the embodiment of the present application, as shown in FIG. Figure 3As shown, the heating device 2 further includes a heating disk 21, the heating disk 21 is connected to the bottom plate 11, and the resistor 222 is connected to the heating disk 21. The heating disk 21 can be welded to the bottom plate 11 to ensure the reliability of the connection between the heating disk 21 and the bottom plate 11. At the same time, the heating disk 21 can facilitate the arrangement of the resistor 222, and can ensure the accuracy of the setting position of the resistor 222 and the installation reliability.

[0069] In one embodiment, the heating plate 21 may be made of structural steel material. After the heating plate 21 is fixedly connected to the bottom plate 11, it is beneficial to improve the structural strength of the bottom plate 11, achieve side energy absorption, prevent side collisions, and improve the safety of the power battery.

[0070] In one embodiment, if Figure 3 As shown, the heating plate 21 may be provided with a plurality of positioning grooves 211, and the resistor 222 is disposed in the positioning grooves 211. The positioning grooves 211 can limit the position of the resistor 222, and ensure the stability of the resistor 222 installed on the heating plate 21.

[0071] In one embodiment, Figure 4 A partial cross-sectional view of a heating assembly 22 provided in one embodiment of the present application, as shown in FIG. Figure 4 As shown, the heating device 2 includes a plurality of heating components 22, each of which includes a heating film 221 and a plurality of resistors 222, and the plurality of resistors 222 can be encapsulated in the heating film 221. The heating film 221 can constrain and position the resistors 222, and can realize the installation of the plurality of resistors 222 wrapped in the heating film 221 onto the heating plate 21 as a whole, which is convenient for operation, can also ensure the installation accuracy of the resistors 222 on the heating plate 21, and can provide protection for the resistors 222. In some other embodiments, Figure 5 A partial cross-sectional view of a heating assembly 22 provided in another embodiment of the present application is shown in FIG. Figure 5 As shown, the resistor 222 can also be fixed on the surface of the heating film 221 .

[0072] In one embodiment, the multiple resistors 222 in the heating film 221 can all be the same resistors 222, so that it is easy to determine the installation position of the heating component 22 on the heating disk 21. For example, when the resistors 222 encapsulated in a heating film 221 are all resistors 222 with larger heating power, the heating component 22 can be set as a whole in the edge area 2b of the heating disk 21; when the resistors 222 encapsulated in a heating film 221 are all resistors 222 with smaller heating power, the heating component 22 can be set as a whole in the middle area 2a of the heating disk 21.

[0073] In one embodiment, the multiple resistors 222 in the heating film 221 may also be resistors 222 with different heating powers, that is, the heating film may include resistors 222 with larger heating power, or resistors 222 with smaller heating power. Among them, as described above, the resistors 222 with larger heating power or the resistors 222 with smaller heating power can be achieved by adjusting the volume of the resistors 222, which will not be repeated here. In this embodiment, for a heating component 22, the position of the heating component 22 corresponding to the resistor 222 with larger heating power can be set in the edge area 2b of the heating disk 21, and the position of the heating component 22 corresponding to the resistor 222 with smaller heating power can be set in the middle area 2a of the heating disk 21. Thus, different parts of a heating component 22 can be located in the middle area 2a and the edge area 2b of the heating disk 21, respectively, and can be flexibly set according to different heating requirements of the battery cell 3, with strong versatility.

[0074] In addition, the distance between each resistor 222 in the heating film 221 can also be flexibly set according to the heating requirement of the battery cell 3, which is not limited in this embodiment.

[0075] In one embodiment, the heating component 22 can be disposed as a whole in the positioning groove 211, and the thickness of the heating component 22 is less than or equal to the depth of the positioning groove 211. The heating component 22 will not protrude from the surface of the heating plate 21, so that the flatness of the surface of the heating plate 21 can be ensured, which is convenient for the battery cell 3 to contact and stably support on the heating plate 21. Exemplarily, the thickness of the heating component 22 is equal to the depth of the positioning groove 211, that is, after the heating component 22 is installed in the positioning groove 211, the surface of the heating component 22 that protrudes from the positioning groove 211 is flush with the surface of the heating plate 21, and the battery cell 3 can contact and stably support on the heating plate 21 and the heating component 22 at the same time. At the same time, the heating component 22 can directly conduct the generated heat to the battery cell 3 by contacting the battery cell 3, thereby realizing rapid heating of the battery cell 3.

[0076] In one embodiment, if Figure 3 As shown, the positioning groove 211 may be a strip groove. Exemplarily, when the positioning groove 211 is a strip groove, the strip groove may extend in the length direction X or the width direction Y of the heating plate 21. The strip groove may be a straight groove, such as a rectangular groove; the strip groove may also be an arc groove, such as a wavy groove. There are multiple strip grooves, and the multiple strip grooves may be arranged in parallel and at intervals. Some of the strip grooves may be located in the middle area 2a, and some of the strip grooves may be located in the edge area 2b.

[0077] In some other embodiments, the positioning groove 211 may also be an annular groove, which is not limited in this embodiment.

[0078] In one embodiment, Figure 6A top view of a heating plate provided in one embodiment of the present application, as shown in FIG. Figure 6 As shown, the positioning groove 211 may include a first groove 211a and a second groove 211b, the first groove 211a is located in the middle area 2a, and the second groove 211b is located in the edge area 2b. The heating powers of the multiple resistors 222 of the heating assembly 22 installed in the first groove 211a can be consistent, and the heating powers of the resistors 222 of the heating assembly 22 installed in the second groove 211b can be consistent, and the heating power of the resistors 222 of the heating assembly 22 installed in the first groove 211a is smaller, and the heating power of the resistors 222 of the heating assembly 22 installed in the second groove 211b is larger.

[0079] In one embodiment, Figure 7 A top view of a heating plate provided in another embodiment of the present application, as shown in FIG. Figure 7 As shown, the positioning groove 211 may further include a third groove 211c, at least part of the third groove 211c is located in the middle area 2a, and at least another part of the third groove 211c is located in the edge area 2b. The multiple resistors 222 in the heating component 22 installed in the third groove 211c may have different heating powers, and the position of the resistor 222 corresponding to the larger heating power in the heating component 22 may be located in the edge area 2b, and the position of the resistor 222 corresponding to the smaller heating power in the heating component 22 may be located in the middle area 2a.

[0080] The heating plate 21 may be provided with the first groove 211a, the second groove 211b and the third groove 211c at the same time, or only with the first groove 211a and the second groove 211b, or only with the third groove 211c. In some other embodiments, the first groove 211a and the third groove 211c may be provided at the same time, or the second groove 211b and the third groove 211c may be provided at the same time. Thus, the setting of the positioning groove 211 can be more flexible and can meet the heating requirements of different battery cells 3. The above-mentioned different setting methods of the positioning groove 211 all need to cover the middle area 2a and the edge area 2b.

[0081] In one embodiment, Figure 8 A side view of a heating plate provided in an embodiment of the present application, as shown in FIG. Figure 8As shown, a plurality of welding parts 212 are provided on the side of the heating plate 21 away from the positioning groove 211, and the welding parts 212 protrude from the side of the heating plate 21 away from the positioning groove 211. The heating plate 21 is welded and connected to the bottom plate 11 through the welding parts 212. During welding, the protruding welding parts 212 can melt and can be reliably combined with the bottom plate 11, thereby ensuring the reliability of the fixing of the heating plate 21 to the bottom plate 11. Among them, since the welding parts 212 protrude from the surface of the heating plate 21, when the welding parts 212 melt, it will not affect the structure of the heating plate 21 around the welding parts 212, thereby ensuring the reliability of the structure of the heating plate 21.

[0082] The thickness of the location where the positioning groove 211 is provided on the heating plate 21 is relatively small. If the welding portion 212 is provided at a location corresponding to the positioning groove 211, when the welding portion 212 melts at high temperature, it is very easy to cause defects such as melting and burning of the structure around the welding portion 212 and corresponding to the positioning groove 211 on the heating plate 21. For this reason, in this embodiment, if Figure 3 As shown, the positions of the welding portion 212 and the positioning groove 211 are staggered, so as to avoid the welding portion 212 from causing adverse effects on the structure at the positioning groove 211 during high-temperature welding.

[0083] In one embodiment, Fig. 9 The exploded view of the heating device 2 and the bottom plate 11 provided in the embodiment of the present application is as follows: Fig. 9 As shown, a plurality of convex beams 111 may be provided on the bottom plate 11, and the convex beams 111 are welded to the welding portion 212. The convex beams 111 may be in the shape of a long strip, and may extend in the length direction X or the width direction Y of the power battery. A plurality of convex beams 111 may be provided, and the plurality of convex beams 111 may be arranged at intervals, and the plurality of convex beams 111 may be parallel to each other or may be arranged crosswise. By arranging a plurality of convex beams 111 on the bottom plate 11, the structural strength of the bottom plate 11 may be improved, deformation of the bottom plate 11 may be prevented, reliable support for components such as the battery cell 3 and the heating device 2 may be achieved, and effective protection capability may be provided.

[0084] In one embodiment, Fig.10 An exploded diagram of a power battery provided in another embodiment of the present application, such as Fig.10As shown, the power battery also includes an insulating plate 4, which can be arranged between the heating device 2 and the battery cell 3. Exemplarily, the insulating plate 4 can have the same or similar size as the heating film 221, and the insulating plate 4 can be arranged between the heating film 221 and the battery cell 3. Exemplarily, the insulating plate 4 can have the same or similar size as the heating disk 21, can cover the heating disk 21 and the heating device 2, and can separate the battery cell 3 and the heating device 2. Thus, the insulating plate 4 can avoid leakage short circuit between the battery cell 3 and the heating device 2, thereby improving the safety of the power battery. In addition, the battery cell 3 can be supported on the insulating plate 4, and the insulating plate 4 can have a better flatness, which can ensure the stable support of the battery cell 3.

[0085] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A power battery, characterized in that: include: Housing (1); A heating device (2) is arranged in the housing (1), the heating device (2) comprises a middle area (2a) and an edge area (2b), the heating device (2) comprises a plurality of resistors (222), the plurality of resistors (222) are distributed in the middle area (2a) and the edge area (2b), and the heating power of the resistors (222) located in the middle area (2a) is lower than the heating power of the resistors (222) located in the edge area (2b); The battery core (3) is arranged in the housing (1) and connected to the heating device (2).

2. The power battery according to claim 1, characterized in that: The housing (1) comprises a bottom plate (11), the heating device (2) further comprises a heating disk (21), the heating disk (21) is connected to the bottom plate (11), and the resistor (222) is connected to the heating disk (21).

3. The power battery according to claim 2, characterized in that: The heating plate (21) is provided with a plurality of positioning grooves (211), and the resistors (222) are arranged in the positioning grooves (211).

4. The power battery according to claim 3, characterized in that: The heating device (2) comprises a plurality of heating components (22), each of the heating components (22) comprises a heating film (221) and a plurality of resistors (222), and the plurality of resistors (222) are encapsulated in the heating film (221).

5. The power battery according to claim 4, characterized in that: The thickness of the heating component (22) is less than or equal to the depth of the positioning groove (211).

6. The power battery according to claim 3, characterized in that: The positioning groove (211) is a strip-shaped groove; the positioning groove (211) comprises a first groove (211a) and a second groove (211b), the first groove (211a) is located in the middle area (2a), and the second groove (211b) is located in the edge area (2b); and / or, The positioning groove (211) comprises a third groove (211c), at least part of the third groove (211c) is located in the middle area (2a), and at least another part of the third groove (211c) is located in the edge area (2b).

7. The power battery according to claim 3, characterized in that: A plurality of welding portions (212) are provided on a side of the heating plate (21) facing away from the positioning groove (211); the welding portions (212) protrude from a side of the heating plate (21) facing away from the positioning groove (211); and the heating plate (21) is welded to the bottom plate (11) via the welding portions (212).

8. The power battery according to claim 7, characterized in that: A plurality of convex beams (111) are provided on the bottom plate (11), and the convex beams (111) are connected to the welding portion (212) by welding.

9. The power battery according to any one of claims 1 to 8, characterized in that: Along the thickness direction (Z) of the power battery, the ratio of the projected area of ​​the middle region (2a) to the projected area of ​​the heating device (2) is between 1 / 2 and 2 / 3.

10. The power battery according to any one of claims 1 to 8, characterized in that: It also comprises an insulating plate (4), wherein the insulating plate (4) is arranged between the heating device (2) and the battery core (3).

11. A vehicle, characterized in that: A power battery comprising any one of claims 1 to 10.

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