Battery and energy storage equipment

Abstract

The embodiment of the utility model provides a battery and energy storage equipment, and relates to the technical field of energy storage, the battery comprises a shell and a battery cell located in the shell, the battery cell is provided with a positive tab and a negative tab so as to be electrically connected with a positive pole and a negative pole, in addition, the battery cell is further connected with a heat-conducting tab, and the heat-conducting tab is electrically connected with the positive pole and the negative pole. The heat-conducting tab is connected to a current collector of a positive plate or a current collector of a negative plate of the battery cell, extends towards the shell and is in contact with the shell, so that heat of the battery cell is directly conducted to the shell from the current collector through the heat-conducting tab, and then is quickly dissipated through the shell. Through cooperation of the positive tab, the negative tab and the heat-conducting tab, heat of the battery cell can be dissipated in time, so that the risk of thermal aggregation of the battery cell is effectively reduced, the risk of thermal runaway of the battery cell is reduced, and the safety performance of the battery is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, and in particular to a battery and an energy storage device. BACKGROUND

[0002] In related technologies, the positive and negative tabs of a battery not only serve the purpose of current conduction and overcurrent, but also serve the purpose of heat dissipation for the battery cell. However, for a battery with large capacity or high energy density, the problem of insufficient heat dissipation capacity of the positive and negative tabs for the battery cell is more obvious, which leads to heat accumulation in the battery cell and easily causes thermal runaway of the battery cell, resulting in large battery loss, reduced service life of the battery, and affected performance of the battery. CONTENT OF THE UTILITY MODEL

[0003] Embodiments of the present application provide a battery and an energy storage device to improve the heat dissipation capacity of the battery cell, reduce the probability of thermal runaway, and improve the service life and performance of the battery.

[0004] In a first aspect, embodiments of the present application provide a battery, which includes a shell, a cover plate, a battery cell accommodated in a receiving cavity formed by the shell and the cover plate, and a positive pole and a negative pole provided on the cover plate. The battery cell includes a positive plate, a negative plate, a separator between the positive plate and the negative plate, a positive tab connected to a current collector of the positive plate, and a negative tab connected to a current collector of the negative plate. The positive tab is configured to be connected to the positive pole, and the negative tab is configured to be connected to the negative pole. Through the connection of the positive tab and the positive pole, heat in the battery cell can be conducted to the positive pole and the shell through the positive tab to achieve rapid heat dissipation. Similarly, through the connection of the negative tab and the negative pole, heat in the battery cell can be conducted to the negative pole and the shell through the negative tab to achieve rapid heat dissipation. In order to further improve the heat dissipation capacity of the battery cell and reduce the risk of heat accumulation in the battery cell, the battery further includes a heat-conducting tab connected to the current collector of the positive plate or the current collector of the negative plate. The heat-conducting tab extends to contact the shell. At least one of the heat-conducting tab connected to the current collector of the positive plate or the heat-conducting tab connected to the current collector of the negative plate is insulated from the shell, that is, the heat-conducting tab connected to the current collector of the positive plate is insulated from the shell, or the heat-conducting tab connected to the current collector of the negative plate is insulated from the shell, or both the heat-conducting tab connected to the current collector of the positive plate and the heat-conducting tab connected to the current collector of the negative plate are insulated from the shell.

[0005] In the embodiment, the current collectors of the positive electrode sheet and the negative electrode sheet are both made of metal material and have excellent heat conduction performance. The current collector of the positive electrode sheet or the current collector of the negative electrode sheet constituting the battery cell is connected with the shell through the heat conduction tab. The current collector of the positive electrode sheet and the current collector of the negative electrode sheet can efficiently conduct heat to the shell through the heat conduction tab, so as to efficiently conduct the heat of the positive electrode sheet or the heat of the negative electrode sheet to the shell, thereby realizing rapid heat dissipation of the battery cell. In the embodiment, part of the heat of the battery cell can be conducted to the outside of the battery through the positive tab and the negative tab, and the heat of the battery cell can be conducted to the shell and finally to the outside of the battery through the heat conduction tab, thereby effectively reducing the risk of heat accumulation of the battery cell and the risk of thermal runaway of the battery cell, so as to improve the service life and safety performance of the battery. In addition, at least one of the heat conduction tab connected with the current collector of the positive electrode sheet and the heat conduction tab connected with the current collector of the negative electrode sheet is insulated from the shell, thereby effectively avoiding the short circuit of the current collector of the positive electrode sheet and the current collector of the negative electrode sheet caused by the heat conduction tab, and effectively avoiding the risk of thermal runaway caused by the short circuit of the positive electrode sheet and the negative electrode sheet.

[0006] In some embodiments, the heat conduction tab includes a metal part connected with the current collector of the positive electrode sheet or the current collector of the negative electrode sheet, and a first insulating coating provided on the surface of the metal part facing the shell. The first insulating coating is in contact with the shell. In the embodiment, the heat conduction tab is in contact with the shell through the first insulating coating, so that the heat conduction tab and the shell are insulated from each other, thereby avoiding the direct electrical connection between the current collector and the shell through the heat conduction tab, avoiding the corrosion of the shell caused by the intercalation of metal cations, and effectively avoiding the thermal runaway caused by the short circuit of the positive electrode sheet and the negative electrode sheet.

[0007] In some embodiments, the positive pole and the negative pole are provided on the cover plate, the positive tab and the negative tab are located on the side of the battery cell facing the cover plate, so as to be connected with the positive pole and the negative pole, and the heat conduction tab is located on the side of the battery cell facing the bottom wall of the shell. In the embodiment, the upper half of the battery cell facing the cover plate can be effectively cooled through the positive tab and the negative tab, and the lower half of the battery cell facing the bottom wall can be effectively cooled through the heat conduction tab, thereby effectively avoiding the problem of heat accumulation in some parts of the battery cell and effectively reducing the problem of thermal runaway of the battery cell, so as to improve the safety performance of the battery.

[0008] In some embodiments, the battery includes positive heat-conductive tabs connected to the current collectors of the positive electrode sheets and negative heat-conductive tabs connected to the current collectors of the negative electrode sheets. The heat generated on the positive electrode sheets of the battery cell can be quickly conducted to the shell through the positive heat-conductive tabs to achieve rapid heat dissipation. The heat generated on the negative electrode sheets of the battery cell can also be quickly conducted to the shell through the negative heat-conductive tabs to achieve rapid heat dissipation. This effectively improves the heat dissipation capacity of the battery cell and reduces the risk of heat accumulation in the battery cell. The positive heat-conductive tabs and the negative heat-conductive tabs are arranged in the width direction of the battery and on the side of the bottom wall of the shell facing the battery cell. Since the positive heat-conductive tabs and the negative heat-conductive tabs are arranged in the width direction of the battery, the uniformity of heat dissipation of the battery cell can be improved, and the risk of short circuiting between the positive heat-conductive tabs and the negative heat-conductive tabs can be avoided.

[0009] In some embodiments, the number of positive heat-conductive tabs is multiple, and the multiple positive heat-conductive tabs are arranged in layers in the thickness direction of the battery. The number of negative heat-conductive tabs is multiple, and the multiple negative heat-conductive tabs are arranged in layers in the thickness direction of the battery. Since the multiple positive heat-conductive tabs are arranged in a group and the multiple negative heat-conductive tabs are arranged in a group, the multiple positive heat-conductive tabs and the multiple negative heat-conductive tabs can be regularly arranged in the shell, which is beneficial to reducing the process difficulty of the battery manufacturing.

[0010] In some embodiments, the battery further includes a bottom support plate and a Mylar film. The Mylar film is wrapped around the outside of the battery cell, and the bottom support plate is arranged on the bottom wall of the shell. The Mylar film has a first through hole corresponding to the position of the heat-conductive tab, and the bottom support plate has a second through hole corresponding to the position of the heat-conductive tab. The heat-conductive tab passes through the first through hole and the second through hole and contacts the bottom wall of the shell. Through the arrangement of the first through hole and the second through hole, the arrangement of the heat-conductive tab can avoid affecting the normal installation of the Mylar film and the bottom support plate. Moreover, the heat-conductive tab can also play a positioning role for the Mylar film and the bottom support plate, so that the Mylar film and the bottom support plate can always maintain a certain range of relative stability with the battery cell, which is beneficial to improving the infiltration effect of the electrolyte on the battery cell.

[0011] In some embodiments, the thickness of the Mylar film in the height direction of the battery is L1, the thickness of the bottom support plate in the height direction of the battery is L2, and the length of the heat-conductive tab in the height direction of the battery is L3, wherein L3≥L1+L2. Since L3≥L1+L2, the force between the Mylar film and the bottom support plate on the side of the bottom wall of the shell facing the battery cell is not too large, so that the flow resistance of the electrolyte between the Mylar film and the bottom support plate can be reduced, and the infiltration capacity of the electrolyte on the battery cell can be effectively improved.

[0012] In some embodiments, the shell comprises a metal shell and a second insulating coating arranged on the inner wall of the metal shell, and the heat-conducting tab extends to contact the second insulating coating. By arranging the second insulating coating, the risk of insulation voltage resistance caused by the falling of particles or dust inside the battery cell to the bottom wall of the shell can be effectively avoided, and the corrosion resistance of the shell can be effectively improved.

[0013] In some embodiments, the thickness of the first insulating coating is 1-200 μm. When the thickness of the first insulating coating is within this range, the required heat conduction efficiency between the heat-conducting tab and the shell can be met on the premise of meeting the insulation condition between the heat-conducting tab and the shell.

[0014] In some embodiments, the thickness of the second insulating coating is 30-200 μm. When the thickness of the second insulating coating is within this range, the required heat conduction efficiency between the heat-conducting tab and the shell can be met on the premise of meeting the insulation condition between the heat-conducting tab and the shell.

[0015] In some embodiments, the positive tab and the negative tab are located on opposite sides of the battery cell in the width direction, the heat-conducting tab of the battery comprises a positive heat-conducting tab connected with the current collector of the positive plate and a negative heat-conducting tab connected with the current collector of the negative plate, and the positive heat-conducting tab and the negative heat-conducting tab are located on opposite sides of the battery cell in the width direction. Since the positive heat-conducting tab and the negative heat-conducting tab are located on opposite sides of the battery cell in the width direction, the heat dissipation capacity of both sides of the battery cell in the width direction can be effectively improved at the same time, so as to reduce the risk of heat aggregation of the battery cell.

[0016] In a second aspect, the embodiments of the present application provide a power storage device, which comprises a shell and a battery according to any one of the first aspect. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below.

[0018] Figure 1 A structural schematic diagram of a battery pack is provided for the embodiments of the present application;

[0019] Figure 2 A structural schematic diagram of a battery is provided for the embodiments of the present application;

[0020] Figure 3 A structural schematic diagram of a battery is provided for the embodiments of the present application; Figure 2 A structural schematic diagram of a battery is provided for the embodiments of the present application;

[0021] Figure 4 A structural schematic diagram of a battery is provided for the embodiments of the present application; Figure 3 A structural schematic diagram of a battery is provided for the embodiments of the present application;

[0022] Figure 5 For Figure 2 A sectional view of a battery in the embodiment at a thermally conductive tab;

[0023] Figure 5A A partial enlarged sectional view of another battery provided by the embodiment of the application;

[0024] Figure 5B A partial enlarged sectional view of another battery provided by the embodiment of the application;

[0025] Figure 6 A structural schematic diagram of another battery provided by the embodiment of the application;

[0026] Figure 7 A structural schematic diagram of another battery provided by the embodiment of the application.

[0027] Explanation of reference signs:

[0028] 1, battery pack; 2, shell; 3, battery;

[0029] 10, shell; 11, bottom wall; 12, cover plate; 13, side wall; 101, metal shell; 102, second insulating coating;

[0030] 20, battery cell; 21, positive plate; 211, current collector; 212, active material layer; 22, negative plate; 221, current collector; 222, active material layer; 23, separator;

[0031] 31, positive tab; 32, negative tab; 33, positive post; 34, negative post;

[0032] 40, thermally conductive tab; 401, metal part; 402, first insulating coating; 41, positive thermally conductive tab; 42, negative thermally conductive tab;

[0033] 50, Mylar film; 51, first through hole;

[0034] 60, bottom plate; 61, second through hole. DETAILED DESCRIPTION

[0035] The following first explains some terms related to the embodiments of the application.

[0036] The terms "first", "second", and the like in the description and in the claims of the present application and in the above drawings are used to distinguish between similar objects and are not necessarily used to describe a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the present application described herein are capable of operation in other sequences than the one illustrated or other than is explicitly described herein. Furthermore, the terms "comprise", "comprising", "include", "including", and the like are intended to cover non-exclusive inclusions, such that a process, method, system, product, or apparatus that comprises a list of steps or elements does not necessarily comprise only those steps or elements in the list, but can include additional steps or elements not expressly listed or inherent to such process, method, product, or apparatus.

[0037] In modern society, there are a large number of devices that rely on electricity to operate, from household appliances to data centers, factory production lines, and power supply has become one of the factors to maintain the normal operation of modern society. Therefore, energy storage devices have developed rapidly and are widely used, such as battery packs, energy storage cabinets using battery packs, uninterruptible power supply cabinets, and even vehicles using battery packs. Energy storage devices can be used to store electrical energy and to power devices that need to operate on electricity. Energy storage devices can be applied in site energy, photovoltaic, household energy storage, commercial and industrial energy storage, large ground power station energy storage, etc.

[0038] With the development of energy storage devices, high-energy-density energy storage devices have been increasingly favored, and are also the direction that energy storage devices need to develop. However, high-energy-density energy storage devices have problems such as low charging and discharging efficiency, poor electrolyte infiltration effect leading to lithium or sodium precipitation, which also leads to reduced service life of the energy storage device and poor user experience.

[0039] Therefore, with reference to Figure 1 The embodiments of the present application provide an energy storage device with high service life and good user experience, such as an energy storage device. Figure 1 For example, the battery pack 1 in the embodiments includes an outer shell 2 and a plurality of batteries 3 arranged in the outer shell 2. The plurality of batteries 3 are arranged in the outer shell 2 to store electrical energy or release electrical energy.

[0040] In order to reduce the probability of thermal runaway of the battery pack 1 and improve the service life of the battery pack 1, the battery pack 1 in the embodiments changes the structure of the battery 3, specifically by improving the heat aggregation of the battery cell of the battery 3 to reduce the probability of thermal runaway of the battery 3 and improve the service safety performance of the battery 3.

[0041] Figure 2 A structural diagram of a battery 3 is provided in the embodiments of the present application.

[0042] With reference to Figure 2The battery 3 comprises a shell 10, a cover plate 12, an electrode core 20 arranged in a receiving cavity formed by the shell 10 and the cover plate 12, a positive pole lug 31 and a negative pole lug 32, and a positive pole column 33 and a negative pole column 34 arranged on the cover plate 12.

[0043] The shell 10 comprises a bottom wall 11 and a plurality of side walls 13 between the bottom wall 11 and the cover plate 12, and the bottom wall 11, the cover plate 12 and the plurality of side walls 13 enclose a receiving cavity for accommodating the electrode core 20. For the convenience of the following description, the battery 3 comprises a height direction Z, a width direction X and a thickness direction Y, wherein the height direction Z is the direction opposite to the cover plate 12 and the bottom wall, that is, the Z direction in the drawing, the width direction X is the X direction in the drawing, and the thickness direction Y is the Y direction in the drawing.

[0044] The shell 10 is made of metal material, for example, can be made of aluminum material.

[0045] The electrode core 20 can be a stacked electrode core 20 or a wound electrode core 20. Specifically, the electrode core 20 comprises a positive pole sheet 21, a negative pole sheet 22 and a diaphragm 23 between the positive pole sheet 21 and the negative pole sheet 22. The electrode core 20 is stacked by the positive pole sheet 21, the diaphragm 23 and the negative pole sheet 22, or the electrode core 20 is wound by the positive pole sheet 21, the diaphragm 23 and the negative pole sheet 22.

[0046] It can be understood that in other embodiments, the positive pole column 33 and the negative pole column 34 can be arranged on different walls of the shell 10, for example, the positive pole column 33 and the negative pole column 34 are arranged on two opposite walls of the shell 10, for example, on the cover plate 12 and the bottom wall 11 respectively.

[0047] Referring to Figure 2 The positive pole lug 31 and the negative pole lug 32 are arranged on the side of the electrode core 20 facing the cover plate 12, the positive pole lug 31 is used for electrically connecting with the positive pole column 33 on the cover plate 12, and the negative pole lug 32 is used for electrically connecting with the negative pole column 34 on the cover plate 12. The positive pole lug 31 is electrically connected with the positive pole sheet 21, and the negative pole lug 32 is electrically connected with the negative pole sheet 22. It can be understood that a plurality of positive pole sheets 21 can be connected with one positive pole lug 31 respectively, and then the plurality of positive pole lugs 31 are connected together, or a plurality of negative pole sheets 22 can be connected with one negative pole lug 32 respectively, and then the plurality of negative pole lugs 32 are connected together. It can be understood that the positive pole lug 31 and the negative pole lug 32 not only can conduct electricity, but also can conduct heat, and can conduct part of the heat of the electrode core 20 to the shell 10 through the positive pole lug 31 and the negative pole lug 32, so as to timely dissipate the heat in the electrode core 20.

[0048] It can be understood that the positions of the positive pole 33 and the negative pole 34 on the shell 10 are matched with the positions of the positive tab 31 and the negative tab 32, for example, when the positive tab 31 and the negative tab 32 are respectively located on the opposite sides of the battery cell 20, the positive pole 33 and the negative pole 34 are respectively arranged on the opposite sides of the shell 10.

[0049] Figure 3 For Figure 2 The exploded view of the battery 3 in the embodiment; Figure 4 For Figure 3 The structure diagram of the heat-conducting tab 40 in the embodiment connecting with the current collector 211 of the positive plate 21 or the current collector 221 of the negative plate 22.

[0050] Referring to Figure 3 , the battery 3 in the embodiment not only includes the positive tab 31 and the negative tab 32, but also additionally adds the heat-conducting tab 40 for conducting the heat generated in the battery cell 20. The heat-conducting tab 40 is in contact with the shell 10, so as to timely transfer the heat generated by the battery cell 20 to the shell 10 and dissipate the heat to the outside of the battery 3 through the shell 10, so as to realize the rapid heat dissipation of the battery cell 20 and reduce the risk of heat accumulation of the battery cell 20, thereby effectively reducing the probability of thermal runaway. Specifically, the heat-conducting tab 40 is connected with the positive plate 21 or the negative plate 22, so that the positive plate 21 or the negative plate 22 can directly conduct the heat to the shell 10 through the heat-conducting tab 40, so as to realize heat dissipation.

[0051] Referring to Figure 4 , the positive plate 21 includes the current collector 211 and the active material layer 212 arranged on the surface of the current collector 211, and the negative plate 22 also includes the current collector 221 and the active material layer 222 arranged on the surface of the current collector 221. The current collector 211 of the positive plate 21 can be aluminum, copper, stainless steel, nickel, titanium, and an alloy composed of one or more components of these metals, for example, the current collector 211 of the positive plate 21 of the lithium ion battery 3 usually uses aluminum material. The active material layer 212 of the positive plate 21 can be lithium cobaltate, lithium-rich manganese-based material, lithium nickel cobalt manganese phosphate, lithium iron phosphate, lithium manganese phosphate, and lithium manganate, etc. The current collector 221 of the negative plate 22 can be copper, stainless steel, aluminum, nickel, titanium, and an alloy composed of one or more components of these metals. The active material layer 222 of the negative plate 22 can be carbon (such as natural graphite, artificial graphite), silicon (such as silicon monoxide), lithium metal, and lithium alloy, etc.

[0052] In order to improve the heat conduction capacity of the heat-conducting tab 40, referring to Figure 3 and Figure 4In some embodiments, the heat-conducting tab 40 is directly connected to the current collector 211 of the positive electrode sheet 21 or the current collector 221 of the negative electrode sheet 22, like the positive tab 31 and the negative tab 32. Since the current collectors (211, 221) are usually made of metal materials, such as copper foil or aluminum foil, they have good heat conduction performance. By directly connecting the heat-conducting tab 40 to the current collector 211 of the positive electrode sheet 21 or the current collector 221 of the negative electrode sheet 22, the heat can be directly transferred from the current collectors (211, 221) to the heat-conducting tab 40, which can improve the heat transfer efficiency between the positive electrode sheet 21 or the negative electrode sheet 22 and the heat-conducting tab 40, and thus can improve the heat dissipation capacity of the heat-conducting tab 40 for the battery cell 20, reduce the risk of thermal runaway of the battery cell 20, and improve the safety performance of the battery 3.

[0053] The heat-conducting tab 40 is made of a material with good heat conduction performance, such as a metal material, such as aluminum, nickel, or copper-nickel plating. Since the heat-conducting tab 40 is made of a heat-conducting material, the efficiency of transferring heat from the battery cell 20 to the shell 10 through the heat-conducting tab 40 can be effectively improved, and the heat dissipation capacity for the battery cell 20 can be improved.

[0054] It can be understood that the connection of the heat-conducting tab 40 to the current collector 211 of the positive electrode sheet 21 or the current collector 221 of the negative electrode sheet 22 includes the following three schemes: the heat-conducting tab 40 is connected to the current collector 211 of the positive electrode sheet 21, the heat-conducting tab 40 is connected to the current collector 221 of the negative electrode sheet 22, and the current collector 211 of the positive electrode sheet 21 and the current collector 221 of the negative electrode sheet 22 are both connected to the heat-conducting tab 40. It can be understood that the number of heat-conducting tabs 40 can be multiple, and the number of heat-conducting tabs 40 can be set according to requirements.

[0055] Referring to Figure 3 and Figure 4 In some embodiments, the heat-conducting tab 40 of the battery 3 includes a positive heat-conducting tab 41 and a negative heat-conducting tab 42, i.e., the heat-conducting tab 40 connected to the current collector 211 of the positive electrode sheet 21 is the positive heat-conducting tab 41, and the heat-conducting tab 40 connected to the current collector 221 of the negative electrode sheet 22 is the negative heat-conducting tab 42. The positive heat-conducting tab 41 is mainly used for conducting heat on the positive electrode sheet 21 to the shell 10 to achieve heat dissipation, and the negative heat-conducting tab 42 is mainly used for conducting heat on the negative electrode sheet 22 to the shell 10 to achieve heat dissipation. Through the positive heat-conducting tab 41 and the negative heat-conducting tab 42, the overall heat dissipation performance of the battery cell 20 is greatly improved.

[0056] It can be understood that the number of positive heat-conducting tabs 41 can be multiple, and the multiple positive heat-conducting tabs 41 are connected with the current collectors 211 of the positive plate 21 respectively, and then the multiple positive heat-conducting tabs 41 can be connected together. Similarly, the number of negative heat-conducting tabs 42 can be multiple, and the multiple negative heat-conducting tabs 42 are connected with the current collectors 221 of the negative plate 22 respectively, and then the multiple negative heat-conducting tabs 42 can be connected together.

[0057] Referring to Figure 3 In some embodiments, the positive heat-conducting tabs 41 and the negative heat-conducting tabs 42 are arranged on the side of the battery cell 20 facing the bottom wall 11. Since the positive tabs 31 and the negative tabs 32 are connected on the side of the battery cell 20 facing the cover plate 12, and the positive heat-conducting tabs 41 and the negative heat-conducting tabs 42 are connected on the side of the battery cell 20 facing the bottom wall 11, in the Z direction, the heat of the upper half of the battery cell 20 can be conducted to the outside through the positive tabs 31 and the negative tabs 32 to achieve heat dissipation of the upper half of the battery cell 20, and the heat of the lower half of the battery cell 20 can be conducted to the shell 10 through the positive heat-conducting tabs 41 and the negative heat-conducting tabs 42, and then the heat dissipation of the lower half of the battery cell 20 is achieved. Therefore, through the cooperation of the positive tabs 31, the negative tabs 32, the positive heat-conducting tabs 41 and the negative heat-conducting tabs 42, the heat dissipation performance of each position of the battery cell 20 can be effectively improved, and the heat accumulation in some positions of the battery cell 20 can be effectively avoided, thereby effectively avoiding the thermal runaway of the battery cell 20 due to heat accumulation, and thus the use performance and safety of the battery 3 are effectively improved.

[0058] In some embodiments, the width dimension of the battery 3 is greater than the height dimension of the battery 3, which is greater than the thickness dimension of the battery 3, so that the side of the battery cell 20 facing the cover plate 12 and the side facing the bottom wall 11 are larger in size, and heat is easily accumulated. By arranging the positive tabs 31 and the negative tabs 32 on the side of the battery cell 20 facing the cover plate 12, and arranging the positive heat-conducting tabs 41 and the negative heat-conducting tabs 42 on the side of the battery cell 20 facing the bottom wall 11 of the shell 10, the heat dissipation capacity of the battery cell 20 can be effectively improved.

[0059] Referring to Figure 3 In some embodiments, the battery 3 further comprises a Mylar film 50, which is wrapped on the outer surface of the battery cell 20. The Mylar film 50 can be a polyester film, which can be used as a protective layer of the battery cell 20 to prevent mechanical damage to the battery cell 20 during manufacturing, transportation and use, thereby ensuring the safety and stability of the battery cell 20. The Mylar film 50 also has good electrical insulation performance, which can effectively block current and static electricity, prevent electrical interference between the battery cell 20 and the external environment, and ensure the stability and safety of the battery 3.

[0060] In some embodiments, the melamine film 50 is provided with a first through hole 51 at a position corresponding to the heat-conducting tab 40, so that the heat-conducting tab 40 can pass through the first through hole 51 to contact the shell 10.

[0061] In some embodiments, the number of first through holes 51 is two, and the positive heat-conducting tab 41 and the negative heat-conducting tab 42 correspond to one first through hole 51 respectively, so that the positive heat-conducting tab 41 and the negative heat-conducting tab 42 can pass through the first through hole 51 to contact the shell 10.

[0062] Referring to Figure 3 In some embodiments, the battery 3 further comprises a bottom support plate 60 arranged on the bottom wall 11 of the shell 10, and the bottom support plate 60 is located between the battery cell 20 and the bottom wall 11. The material of the bottom support plate 60 of the battery cell 20 can be selected from various materials, such as plastic and other insulating materials. The bottom support plate 60 is mainly used to support and protect the battery cell 20, prevent the battery cell 20 from shaking or being squeezed in the shell 10 of the battery 3, and thus protect the battery cell 20 from damage. The bottom support plate 60 can also block the direct contact between the battery cell 20 and the bottom wall 11 of the shell 10 of the battery 3, reduce the risk of short circuit, and prolong the service life of the battery 3.

[0063] In some embodiments, the bottom support plate 60 is provided with a second through hole 61 at a position corresponding to the heat-conducting tab 40, and the heat-conducting tab 40 passes through the second through hole 61 to contact the shell 10, so as to transfer the heat of the battery cell 20 to the shell 10 through the heat-conducting tab 40. Specifically, the heat-conducting tab 40 passes through the first through hole 51 and the second through hole 61 in sequence to contact the shell 10.

[0064] In some embodiments, the number of second through holes 61 is two, and the positive heat-conducting tab 41 and the negative heat-conducting tab 42 correspond to one second through hole 61 respectively, so that the positive heat-conducting tab 41 and the negative heat-conducting tab 42 can pass through the second through hole 61 to contact the shell 10.

[0065] Figure 5 For Figure 2 The cross-sectional view of the battery 3 at the heat-conducting tab 40 in the embodiment. It should be noted that, Figure 3 After the battery 3 in the embodiment is cut open at the positions of the positive heat-conducting tab 41 and the negative heat-conducting tab 42, both of them Figure 5 are consistent with those shown in the embodiment, that is, Figure 5 The heat-conducting tab 40 in the embodiment can represent both the positive heat-conducting tab 41 and the negative heat-conducting tab 42.

[0066] Referring to Figure 5In some embodiments, the sum of the thickness L2 of the bottom support plate 60 in the Z direction and the thickness L1 of the Mylar film 50 in the Z direction is slightly less than or equal to the length L3 of the heat-conducting tab 40 in the Z direction. Thus, most of the volume of the heat-conducting tab 40 can be accommodated in the first through hole 51 on the Mylar film 50 and the second through hole 61 on the bottom support plate 60, so that the height of the battery 3 does not need to be increased to accommodate the heat-conducting tab 40, i.e., the heat-conducting tab 40 can be reasonably arranged in the shell 10 without changing the size of the battery 3 itself. In addition, by arranging the heat-conducting tab 40 in the second through hole 61, the heat-conducting tab 40 can cooperate with the second through hole 61 to function as a positioning element, so that the relative position of the battery cell 20 and the bottom support plate 60 can be kept stable, so that the relative position between the through hole on the bottom support plate 60 for the electrolyte to flow through and the battery cell 20 can be kept unchanged, thereby improving the electrolyte infiltration effect of the battery cell 20 through the through hole on the bottom support plate 60. In addition, since the sum of the thickness of the bottom support plate 60 in the Z direction and the thickness of the Mylar film 50 in the Z direction is slightly less than or equal to the length of the heat-conducting tab 40 in the Z direction, and since the heat-conducting tab 40 is in contact with the bottom wall 11 of the shell 10, most of the gravity of the battery cell 20 is directly applied to the bottom wall 11 of the shell 10 under the support of the heat-conducting tab 40, which not only improves the heat conduction efficiency between the heat-conducting tab 40 and the shell 10, but also avoids the gravity of the battery cell 20 directly acting on the Mylar film 50 and the bottom support plate 60, thereby effectively reducing the flow resistance of the electrolyte between the Mylar film 50, the bottom support plate 60 and the battery cell 20, and improving the electrolyte infiltration capacity of the battery cell 20.

[0067] Referring to Figure 3 and Figure 5 In the scheme of conducting heat from the battery cell 20 to the shell 10 through the heat-conducting tab 40, in order to avoid short-circuiting of the positive heat-conducting tab 41 and the negative heat-conducting tab 42, the heat-conducting tab 40 includes a metal portion 401 and an insulating coating, the metal portion 401 is directly connected to the current collector 221 of the positive plate 21 or the negative plate 22, and the insulating coating is located on the surface of the metal portion 401 facing the shell 10, so that direct contact between the metal portion 401 of the heat-conducting tab 40 and the metal shell 10 can be avoided to prevent the shell 10 from undergoing metal cation intercalation reaction and causing corrosion of the shell 10. For convenience of description, the insulating coating of the heat-conducting tab 40 is set as a first insulating coating 402.

[0068] The thickness L4 of the first insulating coating 402 is 1 μm-200 μm, within this range, the heat conduction efficiency between the heat-conducting tab 40 and the shell 10 can be ensured, and short-circuiting of the shell 10 with the positive heat-conducting tab 41 or the negative heat-conducting tab 42 can be avoided.

[0069] Referring to Figure 3 and Figure 5In some embodiments, the part of the negative conductive tab 42 in contact with the shell 10 is made of insulating material. For example, the negative conductive tab 42 includes a metal part 401 and a first insulating coating 402. The metal part 401 is directly connected to the current collector 221 of the negative plate 22, and the first insulating coating 402 is on the surface of the metal part 401 facing the shell 10. Thus, the metal part 401 of the negative plate 22 is prevented from directly contacting the metal shell 10, so as to prevent the metal cation intercalation reaction of the shell 10 and the corrosion of the shell 10.

[0070] The positive conductive tab 41 also includes a metal part 401 and a first insulating coating 402. The metal part 401 is directly connected to the current collector 211 of the positive plate 21, and the first insulating coating 402 is on the surface of the metal part 401 facing the shell 10. Thus, the metal part 401 of the positive plate 21 is prevented from directly contacting the metal shell 10, so as to prevent the metal cation intercalation reaction of the shell 10 and the corrosion of the shell 10.

[0071] In addition, since at least one of the positive conductive tab 41 and the negative conductive tab 42 is made of insulating material, the positive conductive tab 41 and the negative conductive tab 42 are prevented from being short-circuited, so as to reduce the risk of thermal runaway of the battery cell 20.

[0072] It can be understood that the first insulating coating 402 can be provided on the surface of the metal part 401 facing the shell 10, or on other surfaces of the metal part 401. For example, in some embodiments, the first insulating coating 402 is provided on all surfaces of the metal part 401 within 0-20 mm from the end of the metal part 401 facing the shell 10, so as to reduce the probability of the positive conductive tab 41 or the negative conductive tab 42 directly contacting the shell.

[0073] The first insulating coating 402 can be made of organic material or inorganic material, such as polyarylether resin, thermal composite ceramic powder (aluminum oxide, aluminum nitride, etc.), ceramic material, and mixture of high polymer material, etc. The first insulating coating 402 made of the above materials has not only insulating property, but also good thermal conductivity, so as to ensure the insulating property of the conductive tab 40 and the shell 10 while meeting the thermal conductivity of the conductive tab 40.

[0074] Referring to Figure 3 and Figure 5In some embodiments, the part of the shell 10 in contact with the heat-conducting tab 40 is made of an insulating material, for example, the shell 10 includes a metal shell 101 and an insulating coating applied to the inner wall of the metal shell 101. For the convenience of description, the insulating coating of the shell 10 is referred to as a second insulating coating 102, and the positive heat-conducting tab 41 and the negative heat-conducting tab 42 can both be made of a metal material. In this embodiment, by providing the second insulating coating 102, the risk of insulation voltage resistance caused by the particles or dust inside the battery cell 20 falling onto the bottom wall 11 of the shell 10 can be effectively avoided, and the corrosion resistance of the shell 10 can be effectively improved.

[0075] The second insulating coating 102 can be made of a mixture of polyarylether resin, thermal composite ceramic powder (aluminum oxide, aluminum nitride, etc.), ceramic material, and high molecular polymer material, or other insulating materials.

[0076] The thickness L5 of the second insulating coating 102 is 30-200 μm. Within this range, the heat-conducting efficiency between the heat-conducting tab 40 and the shell 10 can be ensured, and the metal shell 101 of the shell 10 can be prevented from being short-circuited with the positive heat-conducting tab 41 or the negative heat-conducting tab 42.

[0077] It can be understood that, in order to prevent the positive heat-conducting tab 41 and the negative heat-conducting tab 42 from being short-circuited, only the part of the heat-conducting tab 40 in contact with the shell 10 needs to be made of an insulating material, or the part of the shell 10 in contact with the heat-conducting tab 40 needs to be made of an insulating material. Figure 5 The illustrated embodiments are only one of the embodiments protected by the present application. For example, at least the following several embodiments are also the schemes to be protected by the present application.

[0078] Embodiment one, for example, Figure 5A , Figure 5A Another partial enlarged sectional view of the battery 3 provided by the embodiment of the present application is shown. The shell 10 is made of a metal material, and the negative heat-conducting tab 42 includes a metal part 401 and a first insulating coating 402. The metal part 401 is directly connected to the current collector 221 of the negative plate 22, and the first insulating coating 402 is located on the surface of the metal part 401 facing the shell 10. Thus, the metal part 401 of the negative plate 22 can be prevented from directly contacting the metal shell 10, so as to prevent the metal shell 10 from occurring metal cation intercalation reaction and being corroded.

[0079] The positive conductive tab 41, like the negative conductive tab 42, comprises a metal portion 401 and a first insulating coating 402, the metal portion 401 is directly connected with the current collector 211 of the positive plate 21, and the first insulating coating 402 is located on the surface of the metal portion 401 facing the shell 10, so that direct contact between the metal portion 401 of the positive plate 21 and the metal shell 10 can be avoided, to prevent the shell 10 from occurring metal cation intercalation reaction and causing corrosion of the shell 10.

[0080] In the second embodiment, the positive conductive tab 41 and the negative conductive tab 42 are both made of metal material. Figure 5B , Figure 5B In the second embodiment, the positive conductive tab 41 and the negative conductive tab 42 are both made of metal material. Figure 5 In the second embodiment, the positive conductive tab 41 and the negative conductive tab 42 are both made of metal material.

[0081] In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. Figure 5 In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. Figure 5 In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here.

[0082] In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. Figure 5 In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. Figure 5 In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here.

[0083] In the third embodiment, the battery 3 is a sodium ion battery 3, the shell 10 is an aluminum shell, and the current collector 221 of the negative plate 22 is made of aluminum material. At this time, the negative conductive tab 42 can be completely made of metal material and in contact with the shell 10, while the positive conductive tab 41 comprises a metal portion 401 and a first insulating coating 402 as in the first embodiment, which will be specifically described in the first embodiment and will not be repeated here. Figure 6 Another structure diagram of the battery 3 provided in the embodiments of the present application.

[0084] Referring to the first embodiment, Figure 6In some embodiments, the electric core 20 is a stacked electric core 20, the positive and negative electrode tabs 31 and 32 are located on opposite sides of the electric core 20 in the width direction X, and the positive and negative heat-conducting tabs 41 and 42 are located on opposite sides of the electric core 20 in the width direction X. Since the positive and negative heat-conducting tabs 41 and 42 are located on opposite sides of the electric core 20 in the width direction X, the heat dissipation capacity of the two sides of the electric core 20 in the width direction X can be effectively improved at the same time, so as to reduce the risk of heat aggregation of the electric core 20.

[0085] Figure 7 Another structural schematic diagram of the battery 3 is provided in the embodiments of the present application.

[0086] Referring to Figure 7 In some embodiments, the electric core 20 is a stacked electric core 20, and the thickness direction Y of the electric core 20 is the stacking direction. The positive and negative electrode tabs 31 and 32 are located on opposite sides of the electric core 20 in the height direction Z, and the positive and negative heat-conducting tabs 41 and 42 are located on opposite sides of the electric core 20 in the width direction X. Since the electrode tabs are arranged in four directions of the electric core 20, the heat of the electric core 20 can be simultaneously conducted to the shell 10 in the four directions of the electric core 20 to achieve heat dissipation, thereby reducing the risk of heat aggregation of the electric core 20.

[0087] The above merely provides a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or replacements within the technical scope disclosed in the present application can be easily thought of by those skilled in the art, and should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery, characterized by, The battery comprises a shell, a cover plate, a battery cell accommodated in a receiving cavity formed by the shell and the cover plate, and a positive pole and a negative pole arranged on the cover plate; The battery cell comprises a positive pole piece, a negative pole piece, a diaphragm, a positive pole lug, a negative pole lug, and a heat-conducting pole lug, the diaphragm is arranged between the positive pole piece and the negative pole piece, the positive pole lug is connected to the current collector of the positive pole piece, the negative pole lug is connected to the current collector of the negative pole piece, the positive pole lug is connected to the positive pole, the negative pole lug is connected to the negative pole, the heat-conducting pole lug is connected to the current collector of the positive pole piece or the current collector of the negative pole piece, the heat-conducting pole lug extends to contact the shell, and at least one of the heat-conducting pole lug connected to the current collector of the positive pole piece or the heat-conducting pole lug connected to the current collector of the negative pole piece is insulated from the shell.

2. The battery of claim 1, wherein, The heat-conducting pole lug comprises a metal part connected to the current collector of the positive pole piece or the current collector of the negative pole piece, and a first insulating coating arranged on the surface of the metal part facing the shell, and the first insulating coating contacts the shell.

3. The battery according to claim 1 or 2, characterized in that, The positive pole lug and the negative pole lug are arranged on the side of the battery cell facing the cover plate, and the heat-conducting pole lug is arranged on the side of the battery cell facing the bottom wall of the shell.

4. The battery according to any one of claims 1 to 3, characterized in that, The heat-conducting pole lug of the battery comprises a positive heat-conducting pole lug connected to the current collector of the positive pole piece and a negative heat-conducting pole lug connected to the current collector of the negative pole piece, and the positive heat-conducting pole lug and the negative heat-conducting pole lug are arranged on the side of the battery cell facing the bottom wall of the shell in the width direction of the battery.

5. The battery of claim 4, wherein, The number of the positive heat-conducting pole lug is plural, and the plural positive heat-conducting pole lugs are arranged in a stack in the thickness direction of the battery, and the number of the negative heat-conducting pole lug is plural, and the plural negative heat-conducting pole lugs are arranged in a stack in the thickness direction of the battery.

6. The battery according to any one of claims 3-5, characterized in that, The battery further comprises a bottom support plate and a Mylar film, the Mylar film is wrapped on the outside of the battery cell, the bottom support plate is arranged on the bottom wall of the shell, the Mylar film is provided with a first through hole at the position corresponding to the heat-conducting pole lug, the bottom support plate is provided with a second through hole at the position corresponding to the heat-conducting pole lug, and the heat-conducting pole lug passes through the first through hole and the second through hole to contact the bottom wall of the shell.

7. The battery of claim 6, wherein, The thickness of the Mylar film in the height direction of the battery is L1, the thickness of the bottom support plate in the height direction of the battery is L2, and the length of the heat-conducting pole lug in the height direction of the battery is L3, wherein L3≥L1+L2.

8. The battery according to any one of claims 1 to 7, characterized in that, The shell comprises a metal shell and a second insulating coating arranged on the inner wall of the metal shell, and the heat-conducting pole lug extends to contact the second insulating coating.

9. The battery of claim 8, wherein, The thickness of the second insulating coating is 1-200 microns.

10. The battery of claim 2, wherein, The thickness of the first insulating coating is 30-200 microns.

11. The battery of claim 1, wherein, The positive pole lug and the negative pole lug are arranged on the opposite sides of the battery cell in the width direction, the heat-conducting pole lug of the battery comprises a positive heat-conducting pole lug connected to the current collector of the positive pole piece and a negative heat-conducting pole lug connected to the current collector of the negative pole piece, and the positive heat-conducting pole lug and the negative heat-conducting pole lug are arranged on the opposite sides of the battery cell in the width direction.

12. An energy storage device, characterized by, The energy storage device comprises a housing and a battery as claimed in any one of claims 1 to 11, the battery being provided within the housing.

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