Electrochemical device and electronic equipment

Abstract

The embodiment of the utility model discloses an electrochemical device and an electronic device, the electronic device comprises the electrochemical device, the electrochemical device comprises a battery cell assembly, the battery cell assembly comprises a plurality of battery cells, the plurality of battery cells are stacked in sequence along a first direction, and the plurality of battery cells are electrically connected; the heating assembly comprises a plurality of heating pieces, one heating piece is attached to the side face of one battery cell in the first direction, and the heating efficiency of the heating pieces located on the battery cells at the two ends in the first direction is higher than that of other heating pieces. The heating efficiency of the heating pieces on the battery cells at the two ends is higher than that of other heating pieces, so that the temperature rising effect of the battery cells at the end positions is improved, the battery cells at the end positions obtain more heat, heat loss of the battery cells at the end positions due to better heat dissipation conditions is counteracted, and the service life of the battery cells at the end positions is prolonged. The temperature difference between the battery cells at the end parts and the battery cells at the middle part is reduced, so that the working stability and the service life of the electrochemical device are improved.

Description

Technical Field

[0001] The utility model belongs to the field of new energy, and in particular relates to an electrochemical device and an electronic device. Background Art

[0002] Lithium-ion electrochemical devices (i.e., lithium-ion batteries) have the advantages of high voltage, large capacity, small size, and light weight, and are widely used in various electronic devices. However, lithium-ion electrochemical devices are sensitive to the temperature of the operating environment. The optimal operating temperature range of most lithium-ion electrochemical devices is 15°C to 35°C. In low-temperature scenarios, especially below 0°C, the charging and discharging efficiency is low. Therefore, in low-temperature environments, lithium-ion electrochemical devices need to be preheated to achieve the minimum temperature requirement for cold start or to place the lithium-ion electrochemical device in a suitable operating temperature range. At present, silicone heating film is mainly used to attach to the side of the lithium-ion electrochemical device to preheat the lithium-ion electrochemical device.

[0003] In the process of realizing the utility model, the inventor of the present utility model found that: a lithium-ion electrochemical device usually includes a plurality of battery cells, which are stacked in sequence and electrically connected, and the area of ​​the battery cells located at the edge position exposed to the air is larger than the area of ​​the battery cells located at the middle position exposed to the air, and the heat dissipation conditions are better, but the area of ​​the silicone heating film distributed on the side of each battery cell is the same, and the heating efficiency of the silicone heating film for each battery cell is the same, but the battery cells at the edge position have good heat dissipation conditions, and their heating effect is obviously not as good as the middle battery cell, which leads to uneven temperature phenomenon of low temperature at both ends of the lithium-ion electrochemical device and high temperature in the middle at the end of heating. The uneven temperature of the battery cells will cause uneven charging and discharging of the battery cells of the lithium-ion electrochemical device, affecting the overall performance of the lithium-ion electrochemical device and shortening the service life of the lithium-ion electrochemical device. Utility Model Content

[0004] In view of the above problems, the embodiments of the present invention provide an electrochemical device and an electronic device including the electrochemical device. In the electrochemical device, the heating efficiency of the heating element on the battery cell at the end position is higher than the heating efficiency of other heating elements, which can reduce the temperature difference of the battery cells at different positions and improve the stability and service life of the electrochemical device.

[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide an electrochemical device, comprising: a battery cell assembly, comprising a plurality of battery cells, the plurality of battery cells are stacked in sequence along a first direction, and the plurality of battery cells are electrically connected; a heating assembly, comprising a plurality of heating elements, one of the heating elements is attached to a side surface of the battery cell along the first direction, wherein, along the first direction, the heating efficiency of the heating elements on the battery cells at both ends is higher than the heating efficiency of other heating elements.

[0006] Optionally, the heating element includes a first heat-conducting film, a second heat-conducting film and a heating element, the heating element is located between the first heat-conducting film and the second heat-conducting film, and the first heat-conducting film of a heating element is attached to a side surface of the battery cell along the second direction.

[0007] Optionally, along the first direction, the heating element area of ​​the heating elements on the battery cells at both ends is larger than the heating element area of ​​other heating elements.

[0008] Optionally, along the first direction, the length of the heating element of the heating elements on the battery cells at both ends is greater than the length of the heating elements of other heating elements.

[0009] Optionally, along the first direction, the material of the heating elements of the heating elements on the battery cells at both ends is different from the material of the heating elements of other heating elements, and the heating efficiency of the heating elements of the heating elements on the battery cells at both ends is higher than the heating efficiency of the heating elements of other heating elements.

[0010] Optionally, along the second direction, projections of the heating elements are all located on the sides of the battery core, and the first direction is perpendicular to the second direction.

[0011] Optionally, the heating component further includes a plurality of connecting members, and any two adjacent heating members are connected via one of the connecting members.

[0012] Optionally, the electrochemical device further comprises a plurality of insulating sheets, an insulating sheet is provided between any two adjacent battery cells, and a gap is formed between any two adjacent battery cells; the height of the connecting member is smaller than the height of the heating member, and along the second direction, the projection of the connecting member is located within the gap.

[0013] Optionally, the electrochemical device further comprises a first end plate, a second end plate and a fastening band, and along the first direction, the battery cell assembly is located between the first end plate and the second end plate, and the fastening band is sleeved on the first end plate, the second end plate and the battery cell assembly.

[0014] In order to solve the above technical problems, another technical solution provided by the present invention is: to provide an electronic device, comprising the electrochemical device as described in any one of the above items.

[0015] In the embodiment of the utility model, the electrochemical device includes a battery cell assembly and a heating assembly, wherein the battery cell assembly includes a plurality of battery cells, the plurality of battery cells are stacked in sequence along a first direction, and the plurality of battery cells are electrically connected; the heating assembly includes a plurality of heating elements, a heating element is attached to the side of a battery cell along a second direction, wherein along the first direction, the heating efficiency of the heating elements on the battery cells at both ends is higher than the heating efficiency of other heating elements, and the first direction is perpendicular to the second direction. Since the heating efficiency of the heating elements on the battery cells at both ends is higher than the heating efficiency of other heating elements, the heating effect of the battery cells at the end positions is improved, so that the battery cells at the end positions obtain more heat, offsetting the heat loss caused by the better heat dissipation conditions of the battery cells at the end positions, and reducing the temperature difference between the battery cells at the end positions and the battery cells at the middle positions at the end of heating, thereby improving the stability and life of the electrochemical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of an electrochemical device in an embodiment of the utility model;

[0017] Figure 2 It is a schematic diagram of an explosion of an electrochemical device in an embodiment of the utility model;

[0018] Figure 3 It is a schematic diagram of the overall structure of a heating element in an embodiment of the utility model.

[0019] In the accompanying drawings, each reference numeral represents:

[0020] 100. Electrochemical device;

[0021] 1. battery cell assembly; 11. battery cell; 12. gap; 13. battery cell group; 131. first battery cell group; 132. second battery cell group;

[0022] 2. Heating assembly; 21. Heating element; 22. Connecting element; 211. First heat-conducting film; 212. Second heat-conducting film;

[0023] 3. First end plate; 31. Main plate; 32. First side plate; 33. Second side plate; 34. Position limiting protrusion; 35. First bayonet; 36. Second bayonet; 37. First through hole; 38. Second through hole;

[0024] 4. Second end plate; 5. Fastening belt. DETAILED DESCRIPTION

[0025] The embodiments of the utility model are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the utility model, and cannot be understood as limiting the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the utility model.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "circumferential", "radial" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 present invention.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying 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 one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0028] Please also read Figure 1 and Figure 2 The electrochemical device 100 includes a battery cell assembly 1, a heating assembly 2, a first end plate 3, a second end plate 4 and a fastening band 5. The battery cell assembly 1 is located between the first end plate 3 and the second end plate 4; the fastening band 5 is sleeved on the first end plate 3, the second end plate 4 and the battery cell assembly 1, thereby fixing the first end plate 3, the second end plate 4 and the battery cell assembly 1. The heating assembly 2 is attached to the battery cell assembly 1, and the heating assembly 2 is used to heat the battery cell assembly 1 to improve the performance of the battery cell assembly 1 in a low temperature environment.

[0029] For the above cell assembly 1, please refer to Figure 2The battery cell assembly 1 includes a plurality of battery cells 11 and a plurality of insulating sheets. The plurality of battery cells 11 are stacked in sequence along a first direction, and the plurality of battery cells 11 are connected in series or in parallel. There is an insulating sheet between any two adjacent battery cells 11, and the insulating sheet is used to isolate the two adjacent battery cells 11 to reduce the probability of a short circuit between the two battery cells 11. When the insulating sheet is arranged between two adjacent battery cells 11, the insulating sheet will increase the distance between the two adjacent battery cells to form a gap 12.

[0030] In some embodiments, the battery cell assembly 1 is composed of 16 battery cells 11, which are divided into two battery cell groups 13, each battery cell group 13 contains 8 battery cells 11, wherein 8 battery cells 11 are stacked in sequence along the first direction to form a first battery cell group 131, and the other 8 battery cells 11 are stacked in sequence along the first direction to form a second battery cell group 132. Along the second direction, one side of the first battery cell group 131 and one side of the second battery cell group 132 are abutted together to form the battery cell assembly 1. It should be noted that the composition of the above-mentioned battery cell assembly 1 is only for example and cannot be understood as a limitation of the present invention. In other embodiments, the number of battery cells 11 of the battery cell assembly 1 can be 2, 3, 4, 5, 6, 7, 8, etc., and multiple battery cells 11 can form at least one battery cell group 13.

[0031] For the above heating element 2, please also refer to Figures 1 to 3 The heating component 2 includes multiple heating elements 21 and multiple connecting elements 22. A heating element 21 is attached to the side of a battery cell 11 along a first direction. The heating element 21 is used to generate heat to heat the battery cell 11. Any two adjacent heating elements 21 are connected by a connecting element 22, that is, the connecting element 22 connects the multiple heating elements in series, so that power is supplied to both ends of the heating component 2 along the first direction, and all the heating elements 21 can be started at the same time.

[0032] It is worth noting that the first direction is the direction in which the multiple battery cells 11 are stacked, and the first direction is parallel to the side of the battery cell 11. In addition, a heating element 21 is attached to the side of a battery cell 11 along the first direction means that the heating element 21 is attached to the side of the battery cell 11 piece by piece along the first direction.

[0033] In some embodiments, along the second direction, the projection of the heating element 21 is located on the side of the battery cell 11, so that the heating element 21 is completely located on the side of the battery cell 11, so as to reduce the situation where part of the heat of the heating element 21 is directly dissipated to the external environment when the heating element 21 extends out of the side of the battery cell 11, thereby affecting the heating efficiency. The second direction is perpendicular to the first direction, and the second direction is a direction perpendicular to the side of the battery cell 11.

[0034] In some embodiments, along the third direction, the height of the connector 22 is less than the height of the heating element 21, and along the second direction, the projection of the connector 22 is located within the gap 12, so that the connector 22 does not contact the battery cell 11, wherein the first direction, the second direction, and the third direction are perpendicular to each other. Since the connector 22 does not contact the battery cell, the heat generated by the connector 22 cannot be conducted away by contacting the battery cell 11, therefore, the height of the connector 22 is reduced to reduce the heat generated by the connector 22, which is conducive to reducing the heat accumulation generated at this position, which is easy to cause local dry burning and damage the heating component 2.

[0035] It is worth noting that when the height of the connecting member 22 is smaller than the height of the heating member 21 , a gap is formed between the connecting member 22 and two adjacent heating members, and the projection of the gap along the second direction is located within the gap 12 .

[0036] In some embodiments, along the first direction, the heating efficiency of the heating elements 21 on the battery cells 11 at both ends is higher than that of other heating elements 21. Since the battery cells 11 at both ends expose more surfaces than the middle battery cell 11, the battery cells 11 at both ends dissipate heat faster than the middle battery cell 11. When the heating efficiency of the heating elements 21 on the battery cells 11 at both ends is higher than that of other heating elements 21, the heating effect of the battery cells 11 at the ends can be higher than that of the battery cells 11 in the middle, so that the battery cells 11 at the end positions obtain more heat, offsetting the heat loss caused by the better heat dissipation conditions of the battery cells 11 at the end positions, reducing the temperature difference between the battery cells 11 at the end positions and the battery cells 11 at the middle positions at the end of the heating, and improving the stability and life of the electrochemical device 100.

[0037] In order to achieve the effect that the heating efficiency of the heating elements 21 on the battery cells 11 at both ends is higher than that of other heating elements 21 along the first direction, the heating elements 21 on the battery cells 11 at both ends and the heating elements 21 on the battery cells 11 at other locations may be designed differently, for example:

[0038] (1) Along the first direction, the heating element 21 on the battery cells 11 at both ends has a larger area than the heating element 21 of other heating elements, but the thickness and material of all heating elements 21 are the same. Under the premise that the thickness and material of the heating elements 21 are the same, the larger the area, the greater the heat generated per unit time;

[0039] (2) Along the first direction, the thickness of the heating element 21 on the battery cells 11 at both ends is greater than the thickness of the heating element 21 of the other heating elements, but the area and material of all the heating elements 21 are the same. Under the premise that the area and material of the heating elements 21 are the same, the greater the thickness, the greater the heat generated per unit time;

[0040] (3) Along the first direction, the length of the heating element 21 on the battery cells 11 at both ends is greater than the length of the heating element of the other heating elements 21, but the width, thickness and material of all the heating elements 21 are the same. Under the premise that the width, thickness and material of the heating elements 21 are the same, the longer the length, the greater the heat generated per unit time;

[0041] (4) Along the first direction, the material of the heating element 21 on the battery cells 11 at both ends is different from the material of the heating element of other heating elements 21, and the heating efficiency of the heating element 21 on the battery cells 11 at both ends is higher than the heating efficiency of the heating element of other heating elements 21. For example, the material of the battery cells 11 at both ends is nickel-chromium alloy, and the material of the middle battery cell is copper.

[0042] It should be noted that the above are only examples of several structures of the heating elements, but are not limited to the above structures. Users can choose one or a combination of multiple methods according to actual needs. Alternatively, the end heating element and the middle heating element are different in terms of the area, thickness, length and material of the heating element, but after being combined, the heating efficiency of the heating element 21 on the battery cells 11 at both ends is higher than the heating efficiency of other heating elements 21.

[0043] For the above-mentioned heating element 21, please refer to Figure 2 The heating element 21 includes a first heat-conducting film 211, a second heat-conducting film 212 and a heating element (not shown), the first heat-conducting film 211 and the second heat-conducting film 212 are respectively located on both sides of the heating element, the first heat-conducting film 211 and the second heat-conducting film 212 are used to conduct heat and protect the internal heating element, and the first heat-conducting film 211 (or the second heat-conducting film 212) of a heating element 21 is attached to the side of a battery cell 11 along the second direction, so that the heat generated by the heating element can be transferred to the battery cell 11 through the first heat-conducting film 211 or the second heat-conducting film 212. In some embodiments, the heating element can be a metal foil or a metal wire or other heat-generating material.

[0044] In some embodiments, see Figure 2 , a heating component 2 is attached to both sides of each battery cell group 13 along the second direction (the two heating components 2 located between the two battery cell groups 13 are not shown), that is, the electrochemical device 100 has a total of 4 groups of heating components 2, and the size, shape and heating power of each group of heating components 2 are the same, which is convenient for heating both sides of the battery cells 11 of each battery cell group 13, so that the battery cell assembly 1 is evenly heated. Along the second direction, the projections of the heating elements 21 are all located on the sides of the battery cells 11 to avoid the heating elements 21 being attached to positions where there are no battery cells 11. A heating element 21 is attached to the side of a battery cell 11 along the second direction, which is convenient for heating each battery cell 11.

[0045] For the first end plate 3, the second end plate 4 and the fastening belt 5, please refer to Figure 1 and Figure 2 The battery cell assembly 1 is located between the first end plate 3 and the second end plate 4, the first end plate 3 is respectively abutted against the two side surfaces of the battery cell assembly 1 along the first direction, and the fastening belt 5 is sleeved on the first end plate 3, the second end plate 4 and the battery cell assembly 1 to fix the position of the battery cell 11.

[0046] In some embodiments, see Figure 2 The first end plate 3 and the second end plate 4 are of the same size and shape. The first end plate 3 includes a main board 31, a first side plate 32 and a second side plate 33. One end of the first side plate 32 is fixed to the main board 31, and the other end extends in a direction away from the battery cell assembly 1. One end of the second side plate 33 is fixed to the main board 31, and the other end extends in a direction away from the battery cell assembly 1. Two limiting protrusions 34 are symmetrically arranged at both ends of the main board 31. Two mutually symmetrical first bayonet holes 35 are formed between the limiting protrusions 34 and the first side plate 32. Two mutually symmetrical second bayonet holes 36 are formed between the limiting protrusions 34 and the second side plate 33. A first through hole 37 and a second through hole 38 are symmetrically arranged in the middle of the main board 31. The first through hole 37 and the two first bayonet holes 35 are located in the same plane, and the second through hole 38 and the two second bayonet holes 36 are located in the same plane. The first bayonet 35, the first through hole 37 and the second through hole 38 of the second bayonet 36 are all used for the fastening belt 5 to pass through, and the main board 31, the first side plate 32 (or the second side plate 33) and the limiting protrusion 34 jointly play a role in limiting the fastening belt 5. In this embodiment, four fastening belts 5 are provided to fix the battery cell assembly 1, the first end plate 3 and the second end plate 4 to prevent the battery cell 11 from shifting during the use of the electrochemical device 100.

[0047] In the embodiment of the utility model, the electrochemical device 100 includes a battery cell assembly 1 and a heating assembly 2, wherein the battery cell assembly 1 includes a plurality of battery cells 11, the plurality of battery cells 11 are stacked in sequence along a first direction, and the plurality of battery cells 11 are electrically connected; the heating assembly 2 includes a plurality of heating elements 21, a heating element 21 is attached to the side of a battery cell 11 along a second direction, wherein along the first direction, the heating efficiency of the heating elements 21 on the battery cells 11 at both ends is higher than the heating efficiency of other heating elements 21. Since the heating efficiency of the heating elements 21 on the battery cells 11 at both ends is higher than the heating efficiency of other heating elements 21, the heating effect of the battery cells 11 at the end positions is improved, so that the battery cells 11 at the end positions obtain more heat, offsetting the heat loss caused by the better heat dissipation conditions of the battery cells 11 at the end positions, and reducing the temperature difference between the battery cells 11 at the end positions and the battery cells 11 at the middle positions at the end of heating, thereby improving the working stability and life of the electrochemical device 100.

[0048] In addition, the present invention further provides an electronic device, which includes the electrochemical device 100 described above. The specific embodiments of the electronic device can refer to the electrochemical device 100 described above, which will not be described in detail here.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrochemical device, characterized in that: include: A battery cell assembly, comprising a plurality of battery cells, wherein the plurality of battery cells are stacked in sequence along a first direction and the plurality of battery cells are electrically connected; The heating assembly comprises a plurality of heating elements, wherein one of the heating elements is attached to a side surface of a battery cell along a first direction, wherein along the first direction, the heating efficiency of the heating elements on the battery cells at both ends is higher than the heating efficiency of other heating elements.

2. The electrochemical device according to claim 1, characterized in that The heating element comprises a first heat-conducting film, a second heat-conducting film and a heating element, wherein the heating element is located between the first heat-conducting film and the second heat-conducting film, and the first heat-conducting film of a heating element is attached to a side surface of a battery core along a second direction.

3. The electrochemical device according to claim 2, characterized in that Along the first direction, the heating element area of ​​the heating elements on the battery cells at both ends is larger than the heating element area of ​​other heating elements.

4. The electrochemical device according to claim 2, characterized in that Along the first direction, the length of the heating element of the heating elements on the battery cells at both ends is greater than the length of the heating elements of other heating elements.

5. The electrochemical device according to claim 2, characterized in that Along the first direction, the material of the heating elements of the heating elements on the battery cells at both ends is different from that of the heating elements of other heating elements, and the heating efficiency of the heating elements of the heating elements on the battery cells at both ends is higher than that of the heating efficiency of other heating elements.

6. The electrochemical device according to any one of claims 2 to 5, characterized in that: Along the second direction, projections of the heating elements are all located on the sides of the battery core, wherein the first direction is perpendicular to the second direction.

7. The electrochemical device according to claim 6, characterized in that The heating assembly further comprises a plurality of connecting members, and any two adjacent heating members are connected via one of the connecting members.

8. The electrochemical device according to claim 7, characterized in that The electrochemical device further comprises a plurality of insulating sheets, wherein an insulating sheet is provided between any two adjacent battery cells, and a gap is formed between any two adjacent battery cells; The height of the connecting member is smaller than the height of the heating member, and along the second direction, the projection of the connecting member is located within the gap.

9. The electrochemical device according to any one of claims 2 to 5, characterized in that: The electrochemical device further comprises a first end plate, a second end plate and a fastening band. Along a first direction, the battery cell assembly is located between the first end plate and the second end plate, and the fastening band sleeves the first end plate, the second end plate and the battery cell assembly.

10. An electronic device, characterized in that: Comprising the electrochemical device according to any one of claims 1 to 9.

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