Battery and electric device

Abstract

The present disclosure provides a battery and a power consumption device. The battery comprises: an electric core comprising an electrode assembly and a tab connected with the electrode assembly; and a protection plate comprising an electric connection layer, wherein the electric connection layer comprises an electric connection part, the electric connection part comprises a first connection layer and a second connection layer connected with the first connection layer, the first connection layer comprises a first metal, the second connection layer comprises a second metal, the melting point of the second metal is greater than the melting point of the first metal, and the tab is welded to the second connection layer. The present disclosure can cancel the nickel sheet under the condition of guaranteeing the welding performance, thereby reducing the process flow and the cost, and further facilitating the improvement of the battery performance. In addition, it is also beneficial to reduce the size of the battery, and further facilitate the improvement of the volume energy density of the battery.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of batteries, and in particular to a battery and a power consumption device. BACKGROUND

[0002] Due to the characteristics of high energy density, multiple cycles and long storage time, secondary batteries such as lithium ion batteries are widely used in power consumption devices such as mobile phones, wristwatches, earphones, electric vehicles, electric cars, intelligent storage devices, and unmanned aerial vehicles.

[0003] In order to avoid overcharging, overdischarging and short circuit of the battery, usually, the lithium ion battery has a protection plate connected with the tab of the electrode core. In the related art, the welding method of the protection plate and the tab is: first, two L-shaped nickel sheets are attached and welded on the protection plate, then the L-shaped nickel sheet is welded with the tab, and the battery is formed through bending and film pasting processes. This electrical connection method of the battery has high cost and complex process, which consumes time and effort, and is not conducive to reducing production cost. Secondly, the welding through the nickel sheet also increases the size of the finished battery, which is not conducive to improving the volumetric energy density of the battery. SUMMARY

[0004] The purpose of the present disclosure is to provide a battery and a power consumption device to facilitate reducing production cost, improving battery performance and volumetric energy density.

[0005] The first aspect of the present disclosure provides a battery, comprising: an electrode core, the electrode core comprising an electrode assembly and a tab connected with the electrode assembly; a protection plate, the protection plate comprising an electrical connection layer, the electrical connection layer comprising an electrical connection part, the electrical connection part comprising a first connection layer and a second connection layer connected with the first connection layer, the first connection layer comprising a first metal, the second connection layer comprising a second metal, the melting point of the second metal being greater than or equal to the melting point of the first metal, the tab being welded to the second connection layer.

[0006] In the present disclosure, the tab of the battery cell is directly welded with the protection plate to realize electrical connection, and no adapter welding through a nickel sheet is needed. Specifically, a second connection layer is formed on the first connection layer, so that the tab can be directly welded with the second connection layer. In addition, the type of the second metal of the second connection layer can be flexibly set. The second metal of the second connection layer can be a metal having good welding performance with the material of the tab, so that the welding difficulty of the second connection layer and the tab is reduced, and the reliability is improved. The tab can be easily and firmly welded on the second connection layer, and the strength of the welding position also meets the performance requirements of the battery, and is not prone to welding defects such as welding corrosion, false welding, brittle fracture and the like. Therefore, the present disclosure can reduce the process flow and cost under the condition of ensuring the welding performance, thereby being beneficial to improve the battery performance and reduce the temperature rise. In addition, after the nickel sheet is cancelled, it is also beneficial to reduce the size of the battery, thereby being beneficial to improve the volume energy density of the battery. At the same time, it is also beneficial to reduce the impedance of the circuit, reduce the power consumption of the battery during use, reduce the generation of heat, improve the use time of the battery, and thereby improve the service life and user experience of the battery.

[0007] The battery according to the embodiments of the present disclosure can also have the following additional technical features:

[0008] In some embodiments of the present disclosure, the difference between the melting point of the second metal and the melting point of the first metal is less than or equal to 100°C. In this way, the melting points of the second metal and the first metal are close, thereby being beneficial to improve the welding performance of the two and reduce the difficulty of forming the composite layer structure.

[0009] In some embodiments of the present disclosure, the tab includes a first tab and a second tab, and the material of the first tab includes a third metal, and the melting point of the first metal is greater than the melting point of the third metal. When the first tab is overlapped with the protection plate for welding, the third metal of the first tab and the second metal of the second connection layer of the electrical connection part can adopt two metals having good welding performance, thereby being beneficial to improve the welding performance between the first tab and the electrical connection part.

[0010] In some embodiments of the present disclosure, the material of the second tab includes the second metal or a combination of the second metal and the first metal. When the second tab is overlapped with the protection plate for welding, the second metal or the combination of the second metal and the first metal of the second tab directly contacts with the second connection layer of the electrical connection part. Since the melting points of the second tab and the second connection layer of the electrical connection part are the same or similar, the second tab and the protection plate can be effectively welded together.

[0011] In some embodiments of the present disclosure, the electric connection part includes a first electric connection part and a second electric connection part, and each of the first electric connection part and the second electric connection part includes a first connection layer and a second connection layer connected to the first connection layer. The electric connection part includes the first electric connection part and the second electric connection part, and both of them are composite layer structures. The first and second tabs can be directly welded with the first and second electric connection parts, respectively, so as to realize the electric connection between the protection plate and the tabs.

[0012] In some embodiments of the present disclosure, the first metal includes copper, the second metal includes nickel or a nickel-containing alloy, and the third metal includes aluminum. This embodiment can cancel the nickel sheet under the condition of guaranteeing the welding performance, thereby reducing the process flow and the cost, and further improving the battery performance. In addition, it is also beneficial to reduce the size of the battery, thereby improving the volume energy density of the battery. At the same time, it is also beneficial to reduce the impedance of the circuit, reduce the power consumption of the battery during use, reduce the generation of heat, improve the use time of the battery, and further improve the life and user experience of the battery.

[0013] In some embodiments of the present disclosure, the protection plate further includes:

[0014] a substrate substrate;

[0015] at least one circuit layer, the at least one circuit layer being arranged on one side of the substrate substrate;

[0016] a metal insulation layer, the metal insulation layer being arranged on a side of the circuit layer away from the substrate substrate, the electric connection layer being arranged on a side of the metal insulation layer away from the circuit layer, and the circuit on the circuit layer being connected with the first electric connection part and the second electric connection part through a through hole on the metal insulation layer;

[0017] a first flame-retardant layer, the first flame-retardant layer being arranged on a side of the electric connection layer away from the metal insulation layer, and the first flame-retardant layer being provided with a hollow area for exposing the electric connection part;

[0018] a second flame-retardant layer, the second flame-retardant layer being arranged on the other side of the substrate substrate. This embodiment illustrates the specific structure of the protection plate. The present disclosure further provides a metal insulation layer between the electric connection layer and the circuit layer. By arranging the metal insulation layer, it is beneficial to reduce the probability of damaging the circuit when the tab is welded with the protection plate and penetrates to the circuit layer, thereby improving the welding safety.

[0019] In some embodiments of the present disclosure, the material of the metal insulation layer includes at least one of copper, aluminum, nickel, a copper-containing alloy, an aluminum-containing alloy, and a nickel-containing alloy. In this way, it is beneficial to reduce the types of metal materials and reduce the production cost.

[0020] In some embodiments of the present disclosure, the metal insulation layer comprises first insulation portions arranged at intervals, and a projection of the first insulation portions on the electric connection layer covers the electric connection portions. In this way, the energy of the welding at the electric connection portions can be directly blocked, thereby improving the welding safety and avoiding damage to the circuit layer of the protection plate.

[0021] In some embodiments of the present disclosure, the metal insulation layer further comprises a second insulation portion, an edge of the second insulation portion is flush with an edge of the circuit layer, a through hole is arranged on the second insulation portion, and the first insulation portion is arranged in the through hole. The second insulation portion is arranged outside the first insulation portion, so that the second insulation portion and the first insulation portion combine to form a layer structure with the same size as the circuit layer, thereby increasing the contact area between the metal insulation layer and other layer structures, balancing the geometry of the protection plate, reducing stress caused by changes in temperature and humidity, and preventing distortion and warping during the process. At the same time, the overall thickness of the metal insulation layer is kept uniform, thereby improving the flatness of the protection plate. Furthermore, this structure can also improve the heating and cooling performance of the protection plate.

[0022] In some embodiments of the present disclosure, the tab comprises a bent portion, and the electric connection portion is connected to the bent portion. In this way, the space occupied by the tab after welding with the protection plate can be reduced, thereby improving the volume energy density of the battery.

[0023] In some embodiments of the present disclosure, the first tab and the second tab are flat tabs. In this way, the tabs are welded with the protection plate without bending, which on the one hand reduces the space occupied by the tabs, and on the other hand reduces the probability of breakage of the tabs due to bending.

[0024] In some embodiments of the present disclosure, the hollowed-out region on the first flame-retardant layer comprises:

[0025] a region opposite to the first electric connection portion in the first direction;

[0026] a region opposite to the second electric connection portion in the first direction;

[0027] a region opposite to the first tab in the first direction; and

[0028] a region opposite to the second tab in the first direction;

[0029] The first direction is a direction perpendicular to the plate surface of the protection plate. In this way, on the one hand, the strength of the protection plate is ensured. On the other hand, the position opposite to the tab of the first flame-retardant layer is also a hollow area, so that when the tab is welded with the electrical connection part, the tab will not be interfered by the thickness of the flame-retardant layer in the non-welding area, reducing the probability of tab warping, thereby facilitating welding and improving the reliability of welding.

[0030] In some embodiments of the present disclosure, the welding mode of the first tab and the first electrical connection part is laser welding, and the welding mode of the second tab and the second electrical connection part is laser welding. Laser welding has the advantages of fast heating speed, high power density, fast welding speed, and small welding stress and deformation, thereby facilitating improvement of welding effect.

[0031] In some embodiments of the present disclosure, the welding points between the tab and the electrical connection part form a preset pattern, and the preset pattern is one of a circular array, a spiral line array, a plurality of spaced straight lines, a plurality of spaced curved lines, and a meander line. The welding of the tab and the electrical connection part can adopt a specific welding method, so that the welding points can form a variety of different patterns.

[0032] The second aspect of the present disclosure provides a power-using device including the battery of the first aspect. The present disclosure can reduce the process flow and cost under the condition of ensuring the welding performance, thereby facilitating improvement of battery performance. In addition, after the nickel sheet is cancelled, it is also beneficial to reduce the size of the battery, thereby facilitating improvement of the volume energy density of the battery. At the same time, it is also beneficial to reduce the impedance of the circuit, reduce the power consumption of the battery during use, reduce the generation of heat, improve the use time of the battery, and thereby facilitate improvement of the service life of the battery and user experience. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other embodiments can also be obtained by those skilled in the art based on these drawings.

[0034] Figure 1 The structure schematic diagram of the battery of the embodiment of the present disclosure;

[0035] Figure 2 The laminated structure schematic diagram of the protection plate of the embodiment of the present disclosure;

[0036] Figure 3 The exploded structure schematic diagram of the protection plate of the embodiment of the present disclosure;

[0037] Figure 4One of the structure schematic diagrams of the protection plate and the battery cell after welding according to an embodiment of the present disclosure;

[0038] Figure 5 Another structure schematic diagram of the protection plate and the battery cell after welding according to an embodiment of the present disclosure;

[0039] Figure 6 The structure schematic diagram of the first flame-retardant layer according to an embodiment of the present disclosure;

[0040] Figure 7 The structure schematic diagram of the battery cell and the protection plate after welding according to an embodiment of the present disclosure;

[0041] Figure 8 The structure schematic diagram of the preset pattern of the battery shown in FIG. 1. Figure 7

[0042] The reference signs are as follows:

[0043] 10-battery; 100-battery cell; 110-electrode assembly; 120-tab; 200-protection plate; 210-electric connection layer; 220-electric connection part; 220a-first electric connection part; 220b-second electric connection part; 221-first connection layer; 222-second connection layer; 121-first tab; 122-second tab; 230-substrate; 240-circuit layer; 240a-first circuit layer; 240b-second circuit layer; 250-metal isolation layer; 260-first flame-retardant layer; 270-second flame-retardant layer; 251-first isolation part; 252-second isolation part; 2521-via hole; 1211-bent part; F-preset pattern; F1-circular array; F2-helical line array; F3-multiple straight lines arranged at intervals; F4-multiple curved lines arranged at intervals; F5-rectangular line. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present disclosure will be described clearly and detailedly. Obviously, the described embodiments are only some of the embodiments of the present disclosure, but not all the embodiments. Unless otherwise defined, all the technical and scientific terms used herein have the same meanings as those commonly understood by the person skilled in the art of the present disclosure. The terms used in the specification of the present disclosure are only for the purpose of describing the specific embodiments, and are not intended to limit the present disclosure.

[0045] Hereinafter, the embodiments of the present disclosure will be described in detail. However, the present disclosure can be embodied in many different forms, and should not be interpreted as limited to the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided so that the present disclosure can be thorough and complete to one skilled in the art.

[0046] ​Also for purposes of clarity, the dimensions or thicknesses of the various components, layers and / or sections can be exaggerated in the drawings. Throughout this document, the same numbers are used to identify the same components. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. In addition, it should be understood that any reference to a first element of a second element also contemplates a third element that is no different from the first element than the second element.

[0047] Further, the use of "may" when describing embodiments of the present disclosure means that one or more embodiments of the present disclosure "can" include the features and / or functions being

[0048] The professional terms used herein are for the purpose of describing the specific embodiments and are not intended to limit the present disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. It should be further understood that the term "comprising" when used in this specification, specifies the presence of stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0049] Spatially relative terms, such as "on", "above", and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device or apparatus in use or operation in addition to the orientations depicted in the figures. For example, if a device or apparatus in the figures is turned over, elements described as "above" other elements or features would then be oriented "below" the other elements or features. Thus, the exemplary term "above" can encompass both an orientation that is above and below. It will be understood that, although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these terms are not intended to denote a temporal or chronological order. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the exemplary embodiments.

[0050] Each of the various embodiments in the present specification is described in a related manner, and the same or similar parts among the various embodiments can be referred to each other, and each embodiment focuses on the difference from other embodiments.

[0051] Some embodiments of the present disclosure are described in detail below. The embodiments described below and the features in the embodiments can be combined with each other without conflict.

[0052] As Figures 1 to 3As shown, the first aspect of the present disclosure provides a battery 10. The battery 10 includes a battery cell 100 and a protection plate 200. The battery cell 100 includes an electrode assembly 110 and a tab 120 connected to the electrode assembly 110. The protection plate 200 includes an electrical connection layer 210, the electrical connection layer 210 includes an electrical connection portion 220, the electrical connection portion 220 includes a first connection layer 221 and a second connection layer 222 connected to the first connection layer 221, the first connection layer 221 includes a first metal, the second connection layer 222 includes a second metal, the melting point of the second metal is greater than or equal to the melting point of the first metal, and the tab 120 is welded to the second connection layer 222.

[0053] In the present disclosure, the battery cell 100 includes an electrode assembly 110 and a tab 120 connected to the electrode assembly 110. The electrode assembly 110 is a component in the battery that undergoes an electrochemical reaction to generate electrical energy. Generally, the battery cell 100 also includes a housing for placing the electrode assembly 110, which can be an aluminum plastic film. The electrode assembly 110 is located inside the aluminum plastic film housing, the tab 120 is connected to the electrode assembly 110, then extends out of the aluminum plastic film housing, and is sealed and packaged with it. The electrode assembly 110 can be formed by winding or stacking positive and negative electrode sheets. Among them, the positive and negative electrode sheets can include a portion with active material, and the portion with active material can collectively constitute the main part of the electrode assembly 110. Optionally, the active material of the positive electrode sheet can generally be LiCoO2, etc., and the active material of the negative electrode sheet can generally be graphite, etc. The tab 120 is connected to the electrode assembly 110, specifically, the tab 120 is a positive or negative tab connected to the positive or negative electrode sheet in the electrode assembly 110. Further, when the tab 120 is a positive tab, the material of the tab 120 can include at least one of aluminum (Al) or aluminum alloy, and when the tab 120 is a negative tab, the material of the tab 120 can include at least one of nickel (Ni), copper (Cu), or nickel-plated copper (Ni-Cu). In addition, the electrode assembly 110 can also include a separator between the positive and negative electrode sheets. The separator is a porous plastic film, and the commonly used materials include polypropylene (PP), polyethylene (PE), and a copolymer of propylene and ethylene, polyethylene homopolymer, etc.

[0054] The protection plate 200 is connected to the tab 120 by welding. The protection plate 200 is an integrated circuit board for protecting the battery 10, specifically for reducing the probability of overcharging, over-discharging, or open circuit of the battery. In the present disclosure, the protection plate 200 includes an electrical connection layer 210, which is a layer structure in the protection plate 200 that realizes electrical connection with the tab 120. Of course, the protection plate 200 also includes other layer structures in addition to the electrical connection layer 210, such as a flame retardant layer, etc.

[0055] The electric connection layer 210 includes an electric connection part 220, which is a part directly welded with the tab 120. The electric connection part 220 includes a first connection layer 221 and a second connection layer 222 connected to the first connection layer 221, and the tab 120 is overlapped with the second connection layer 222 and welded with the first connection layer 221 through the second connection layer 222. That is, the electric connection part 220 is a composite layer structure, and the second connection layer 222 can be formed on the surface of the first connection layer 221 by electroplating, deposition, sputtering or the like, and the tab 120 is welded with the second connection part 220, thereby realizing the electric connection with the protection plate 200. Among them, the second connection layer 222 and the first connection layer 221 are respectively formed by different materials, and the melting point of the first metal in the first connection layer 221 is less than or equal to the melting point of the second metal in the second connection layer 222.

[0056] The present disclosure designs a technical solution for electrically connecting the tab 120 and the protection plate 200. That is, the tab 120 of the electric core 100 is directly welded with the protection plate 200 to realize the electric connection, without the need for adapter welding through a nickel sheet. Specifically, the electric connection part 220 welded with the tab 120 is a composite metal layer structure, a first metal forms a first connection layer 221, and a second metal forms a second connection layer 222. In this way, the tab 120 can be directly overlapped with the second connection layer 222 and welded with the second connection layer and the first connection layer through the second connection layer. The melting point of the second metal of the second connection layer 222 is higher than or equal to the melting point of the first metal of the first connection layer 221. In the present disclosure, the second connection layer 222 is formed on the first connection layer 221, so that the tab 120 can be directly welded with the protection plate 200 through the second connection layer 222 and the first connection layer 221, without the need for using an L-shaped nickel sheet. Moreover, the category of the second metal of the second connection layer 222 can be flexibly set, and the second metal of the second connection layer 222 can adopt a metal having good welding performance with the material of the tab 120, so as to reduce the welding difficulty of the second connection layer 222 and the tab 120, improve the welding reliability, and make the tab 120 more easily and firmly welded on the second connection layer 222. Moreover, the strength of the welding part also meets the performance requirements of the battery, and is not prone to brittle fracture, welding through or virtual welding and other welding defects. Therefore, the present disclosure can reduce the process flow and cost under the condition of ensuring the welding performance, thereby being conducive to improving the battery performance. In addition, after canceling the nickel sheet, it is also conducive to reducing the size of the battery, thereby being conducive to improving the volume energy density of the battery. At the same time, it is also conducive to reducing the impedance of the circuit, reducing the power consumption of the battery 10 in the use process, reducing the generation of heat, improving the battery use time, and thereby improving the service life and user experience of the battery 10.

[0057] In some embodiments of this disclosure, the difference between the melting point of the second metal and the melting point of the first metal is less than or equal to 100°C. This makes the melting points of the second metal and the first metal relatively close, which is beneficial for improving their welding performance and reducing the difficulty of forming a composite layer structure.

[0058] like Figure 1 As shown, in some embodiments of this disclosure, the tab 120 includes a first tab 121 and a second tab 122. The material of the first tab 121 includes a third metal, and the melting point of the first metal is greater than that of the third metal. The first tab 121 can be the positive electrode tab of the battery. In this embodiment, the material of the first tab 121 includes a third metal, and the melting point of the third metal is less than that of the first metal. When the first tab 121 is welded to the protective plate 200, the third metal of the first tab 121 and the second metal of the second connecting layer 222 of the electrical connection portion 220 can be two metals with good welding performance. For example, the first tab 121 can be made of aluminum, and the second connecting layer 222 can be made of nickel or a nickel-containing alloy. This improves welding performance. Furthermore, when the third metal melts, the temperature is lower than the melting point of the first metal, which helps reduce the probability of the first connecting layer 221 formed by the first metal melting simultaneously due to excessively high welding temperature, thereby improving the welding performance between the first tab 121 and the electrical connection portion 220.

[0059] Furthermore, the material of the second tab 122 includes a second metal or a combination of a second metal and a first metal. For example, the material of the second tab 122 can be nickel or nickel-plated copper. When the second tab 122 is welded to the protective plate 200, the second metal of the second tab 122 is in direct contact with the second connecting layer 222 of the electrical connection portion 220. Since the melting points of the second metal of the second tab 122 and the second metal of the second connecting layer 222 of the electrical connection portion 220 are the same or similar, the second tab 122 and the protective plate 200 can be effectively welded together. The fact that the material of the second tab 122 is the same as the material of the first connecting layer 221 also helps to reduce the types of materials used, thereby reducing production costs.

[0060] like Figure 2As shown, in some embodiments of the present disclosure, the electrical connection portion 220 includes a first electrical connection portion 220a and a second electrical connection portion 220b, both of which include a first connection layer 221 and a second connection layer 222 connected to the first connection layer 221. In this embodiment, the electrical connection portion 220 includes the first electrical connection portion 220a and the second electrical connection portion 220b, and both of which are composite layer structures. The first tab 121 and the second tab 122 can be directly welded with the first electrical connection portion 220a and the second electrical connection portion 220b, respectively. That is, the first tab 121 can be welded with the first electrical connection portion 220a, and the second tab 122 can be welded with the second electrical connection portion 220b; or the first tab 121 can be welded with the second electrical connection portion 220b, and the second tab 122 can be welded with the first electrical connection portion 220a, which is not limited in the present application. In this way, the electrical connection between the protection plate 200 and the tab 120 can be achieved.

[0061] Further, the first metal includes copper, the second metal includes nickel or a nickel-containing alloy, and the third metal includes aluminum. In this embodiment, the three materials are specifically copper (the first metal), nickel or a nickel-containing alloy (the second metal), and aluminum (the third metal). Among them, the melting point of nickel or a nickel-containing alloy is greater than that of copper, and the melting point of copper is greater than that of aluminum. Generally, if aluminum and copper are directly welded, the difference between their metallic properties is relatively large, resulting in poor welding performance and difficulty. Even if it can be welded, the substance formed after welding is relatively brittle, prone to cracking, pitting, and breaking, and ultimately difficult to meet the production needs of the battery. Therefore, in this embodiment, the electrical connection portion 220 is a composite metal layer structure, the first connection layer 221 is a copper layer, and the second connection layer 222 is a nickel or nickel-containing alloy layer. The material of the first tab 121 is aluminum, and the material of the second tab 122 is nickel or a copper-nickel-plated alloy. When welding, the welding performance between the aluminum material of the first tab 121 and the nickel (and nickel-containing alloy) material of the second connection layer 222 is good, and the welding performance between the nickel or copper-nickel-plated alloy material of the second tab 122 and the nickel (and nickel-containing alloy) material of the second connection layer 222 is good. The first tab 121 and the second tab 122 can be directly and firmly welded on the second connection layer 222, and the strength of the welded portion after welding also meets the performance requirements of the battery 10, and is not prone to brittle fracture or poor welding. Therefore, this embodiment can cancel the nickel sheet under the condition of ensuring the welding performance, thereby reducing the process flow and reducing the cost, and further facilitating the improvement of the battery performance. In addition, it is also beneficial to reduce the size of the battery, and thus to improve the volumetric energy density of the battery.

[0062] As shown in FIG. 1, the battery 10 includes a battery body 100 and a protection plate 200. The battery body 100 includes a positive electrode 110, a negative electrode 120, and an electrolyte 130. The protection plate 200 is arranged on the positive electrode 110 and the negative electrode 120, and is used to protect the positive electrode 110 and the negative electrode 120. The protection plate 200 includes an electrical connection portion 220 and a protection layer 210. The electrical connection portion 220 is arranged on the positive electrode 110 and the negative electrode 120, and is used to electrically connect the positive electrode 110 and the negative electrode 120. The protection layer 210 is arranged on the electrical connection portion 220, and is used to protect the electrical connection portion 220. Figure 2 and Figure 3As shown, in some embodiments of the present disclosure, the protection plate 200 further comprises a substrate 230, at least one circuit layer 240, a metal isolation layer 250, a first flame-retardant layer 260, and a second flame-retardant layer 270. The at least one circuit layer 240 is arranged on one side of the substrate 230, the metal isolation layer 250 is arranged on the side of the circuit layer 240 away from the substrate 230, the electrical connection layer 210 is arranged on the side of the metal isolation layer 250 away from the circuit layer 240, and the circuit on the circuit layer 240 is connected to the first electrical connection 220a and the second electrical connection 220b through the through hole on the metal isolation layer 250. The first flame-retardant layer 260 is arranged on the side of the electrical connection layer 210 away from the metal isolation layer 250, and the first flame-retardant layer 260 is provided with a hollow area for exposing the electrical connection 220. The second flame-retardant layer 270 is arranged on the other side of the substrate 230.

[0063] The present embodiment illustrates the specific structure of the protection plate 200. The protection plate 200 generally comprises a hard PCB printed circuit board, a soft FPC flexible circuit board, and a soft and hard combination board combining PCB and FPC. The substrate 230 is the base of the protection plate 200, and generally has a plurality of through holes arranged thereon. The circuit layer 240 is a layer structure with a circuit pattern, and the circuit layer 240 is a basic structure for realizing different functions of the protection plate 200. In one protection plate 200, as shown in Figure 2 Generally, there can be one circuit layer 240, or, as shown in Figure 3 there can be two circuit layers, a first circuit layer 240a and a second circuit layer 240b; or there can be more circuit layers. This mainly depends on the number and complexity of the required circuit. The same circuit of different circuit layers 240 can be connected through the through hole. The electrical connection layer 210 is the layer structure described above for connecting with the tab 120. The first flame-retardant layer 260 and the second flame-retardant layer 270 are respectively arranged on both sides of the substrate 230, and the flame-retardant layer is used for blocking heat conduction to play a flame-retardant role. The present disclosure further provides a metal isolation layer 250 between the electrical connection layer 210 and the circuit layer 240. By providing the metal isolation layer 250, it is beneficial to reduce the probability of damaging the circuit when the tab 120 is welded to the protection plate 200 and penetrates to the circuit layer 240, thereby improving the welding safety.

[0064] Further, the material of the metal isolation layer 250 comprises at least one of copper, aluminum, nickel, copper-containing alloy, aluminum-containing alloy, and nickel-containing alloy. In this way, it is beneficial to reduce the types of metal materials and reduce production costs. It is easy to understand that the material of the metal isolation layer 250 can also be other common metal materials such as iron and zinc, as long as it has a certain strength and can prevent the circuit layer from being welded through.

[0065] As shown in Figure 2 andFigure 3 As shown, in some embodiments of this disclosure, the metal insulating layer 250 includes a first insulating portion 251 spaced apart, and the orthographic projection of the first insulating portion 251 on the electrical connection layer 210 covers the electrical connection portion 220. In this embodiment, the first insulating portion 251 and the electrical connection portion 220 are arranged opposite to each other in the thickness direction of the protective plate 200, and the electrical connection portion 220 is a welding part. This arrangement is beneficial for directly blocking the welding energy at the electrical connection portion 220, thereby improving welding safety and avoiding damage to the circuit layer 240 of the protective plate 200.

[0066] like Figure 3 As shown, in some embodiments of this disclosure, the metal insulating layer 250 further includes a second insulating portion 252, the edge of which is flush with the edge of the circuit layer 240. A through hole 2521 is provided on the second insulating portion 252, and the first insulating portion 251 is disposed within the through hole 2521. In this embodiment, the metal insulating layer 250 includes a second insulating portion 252 and a first insulating portion 251 that are independent of each other. The first insulating portion 251 is used to directly block welding energy, which is beneficial to improving welding safety. The edge of the second insulating portion 252 is flush with the edge of the circuit layer 240, and the first insulating portion 251 is placed within the through hole 2521. That is, the second insulating portion 252 is disposed around the outside of the first insulating portion 251, so that the second insulating portion 252 and the first insulating portion 251 combine to form a layer structure with the same size as the plane of the circuit layer 240. This is beneficial to increase the contact area between the metal insulating layer 250 and other layer structures, thereby balancing the geometry of the protective board 200, reducing stress caused by temperature and humidity changes, and preventing twisting and warping during the process. Simultaneously, maintaining a uniform overall thickness of the metal insulating layer 250 helps improve the flatness of the protective plate 200. Furthermore, the second insulating portion 252 and the first insulating portion 251 can be set to the same thickness, further improving the flatness of the protective plate 200. Moreover, this structure can also improve the heat dissipation and heat distribution performance of the protective plate 200.

[0067] like Figure 4 As shown, in some embodiments of this disclosure, the tab 120 includes a bent portion 1211, and an electrical connection portion 220 is connected to the bent portion 1211. The tab 120 forms the bent portion 1211 by bending, and the electrical connection portion 220 is connected to the bent portion 1211. This helps to reduce the space volume occupied by the tab 120 after it is welded to the protection plate 200, and helps to improve the volumetric energy density of the battery 10.

[0068] like Figure 1 and Figure 5As shown, in some embodiments of the present disclosure, the first tab 121 and the second tab 122 are flat tabs 120. That is, the first tab 121 and the second tab 122 are pre-cut to a preset length. In this way, the tabs 120 are welded to the protective plate 200 without being bent, which on the one hand helps to reduce the space volume occupied by the two, and on the other hand helps to reduce the probability of the tabs 120 being broken due to bending.

[0069] As shown, in some embodiments of the present disclosure, the first tab 121 and the second tab 122 are flat tabs 120. That is, the first tab 121 and the second tab 122 are pre-cut to a preset length. In this way, the tabs 120 are welded to the protective plate 200 without being bent, which on the one hand helps to reduce the space volume occupied by the two, and on the other hand helps to reduce the probability of the tabs 120 being broken due to bending. Figure 6 As shown, in some embodiments of the present disclosure, the hollowed-out area on the first flame-retardant layer 260 includes: an area A opposite the first electrical connection part 220a in the first direction; an area B opposite the second electrical connection part 220b in the first direction; an area C opposite the first tab 121 in the first direction; and an area D opposite the second tab 122 in the first direction. Wherein, the first direction is a direction perpendicular to the plate surface of the protective plate 200, that is, the first direction is Figure 6The length direction of the first flame-retardant layer 260 is defined as the second direction X, and the width direction of the first flame-retardant layer 260 is defined as the third direction Y, and the directions X, Y and Z are perpendicular to each other. The first flame-retardant layer 260 functions to block heat conduction and also improves the strength of the protection plate 200. In order to reduce the influence of the flame-retardant layer 260 on welding and also to maximize the strength of the protection plate 200, a hollowed-out area is provided on the flame-retardant layer 260. Specifically, in a first aspect, the hollowed-out area includes regions A and B opposite the first and second electrical connection portions 220a and 220b in the first direction Z, that is, the first and second electrical connection portions 220a and 220b are exposed and not shielded by the flame-retardant layer 260, thereby facilitating the welding reliability of the first and second electrical connection portions 220a and 220b. In a second aspect, the hollowed-out area also includes regions opposite the first and second tabs 121 and 122 in the first direction Z. That is, when the first and second tabs 121 and 122 are welded to the first and second electrical connection portions 220a and 220b, respectively, in addition to the positions of the first and second electrical connection portions 220a and 220b being hollowed-out areas, the regions C and D corresponding to the orthographic projections of the first and second tabs 121 and 122 on the flame-retardant layer 260 are also hollowed-out areas. At this time, the orthographic projection of the first electrical connection portion 220a on the flame-retardant layer 260 overlaps the orthographic projection of the first or second tab 121 or 122 on the flame-retardant layer 260; correspondingly, the orthographic projection of the second electrical connection portion 220b on the flame-retardant layer 260 overlaps the orthographic projection of the second or first tab 122 or 121 on the flame-retardant layer 260. This arrangement facilitates the strength of the protection plate 200. On the other hand, the positions of the first flame-retardant layer 260 opposite the tabs are also hollowed-out areas (regions C and D), so that when the tabs are welded to the electrical connection portions 220, there is no flame-retardant layer between the tabs and the electrical connection portions 220 between the two ends of the tabs in the third direction Y, the tabs are not disturbed by the thickness of the flame-retardant layer in the non-welding area, the probability of tab warping is reduced, and welding is facilitated and the welding reliability is improved.

[0070] In some embodiments of the present disclosure, the welding method of the first tab 121 to the first electrical connection portion 220a is laser welding, and the welding method of the second tab 122 to the second electrical connection portion 220b is laser welding. In this embodiment, the first tab 121 is electrically connected to the first electrical connection portion 220a, and the second tab 122 is electrically connected to the second electrical connection portion 220b. Furthermore, the electrical connection is achieved by laser welding. Laser welding has the advantages of fast heating speed, high power density, fast welding speed, and small welding stress and deformation. In addition, the laser beam is easy to control, so that the second connection layer 222 and the tab 120 form a specific molten pool, which facilitates the welding effect and ensures that the welded portion after welding meets the performance requirements of the battery 10.

[0071] The welding of the tab 120 to the electrical connection 220 can be performed using a specific welding method, thereby allowing the weld joint to form a variety of different patterns. For example, such as Figure 7 and Figure 8 As shown, in some embodiments of this disclosure, the solder joints between the tab 120 and the electrical connection portion 220 form a preset pattern F, which is one of the following: a circular array F1, a spiral array F2, multiple spaced straight lines F3, multiple spaced curves F4, and a loop F5.

[0072] The second aspect of this disclosure provides an electrical device including the battery 10 described in the first aspect. The tabs 120 of the battery cell 100 are directly welded to the protection board 200 for electrical connection, eliminating the need for nickel strips for transfer welding. In this disclosure, a second connecting layer 222 is formed on the first connecting layer 221, allowing the tabs 120 to be directly welded to the second connecting layer 222 without the need for L-shaped nickel strips. Furthermore, the type of the second metal in the second connecting layer 222 can be flexibly set. The second metal of the second connecting layer 222 can be a metal with good weldability to the material of the tabs 120, thereby reducing the welding difficulty between the second connecting layer 222 and the tabs 120. The tabs 120 can be welded to the second connecting layer 222 more easily and firmly, and the strength of the welded area meets the performance requirements of the battery, reducing the likelihood of brittle fracture or poor welding. Therefore, this disclosure can reduce the process steps and lower costs while ensuring welding performance, thereby improving battery performance. Furthermore, eliminating the nickel plate helps reduce the battery size, thereby increasing the battery's volumetric energy density. It also helps reduce circuit impedance, decrease energy consumption during battery 10 use, reduce heat generation, and extend battery life, thus improving the battery's lifespan and user experience.

[0073] It should be noted that, in this document, relational terms such as “first” and “second” are used merely to distinguish one entity from another, and do not necessarily require or imply any such actual relationship or order between these entities. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or apparatus comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or apparatus.

[0074] The above description is only a preferred embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A battery, characterized in that, include: A battery cell, the battery cell including an electrode assembly and tabs connected to the electrode assembly; A protective board, which is an integrated circuit board, includes a substrate, a circuit layer disposed on one side of the substrate, a metal isolation layer disposed on the side of the circuit layer away from the substrate, an electrical connection layer disposed on the side of the metal isolation layer away from the circuit layer, and a first flame-retardant layer disposed on the side of the electrical connection layer away from the metal isolation layer. The electrical connection layer includes an electrical connection portion, which is exposed through a cutout area disposed on the first flame-retardant layer. The circuits on the circuit layer pass through through holes located on the metal isolation layer and are electrically connected to the electrical connection portion. The electrical connection portion includes a first connection layer and a second connection layer connected to the first connection layer. The first connection layer includes a first metal, and the second connection layer includes a second metal. The melting point of the second metal is greater than or equal to the melting point of the first metal. The tabs are soldered to the second connection layer. The material of the metal insulating layer includes at least one of copper, aluminum, nickel, copper-containing alloys, aluminum-containing alloys, and nickel-containing alloys.

2. The battery according to claim 1, characterized in that, The electrical connection portion includes a first electrical connection portion and a second electrical connection portion, both of which include a first connection layer and a second connection layer connected to the first connection layer.

3. The battery according to claim 2, characterized in that, The electrode includes a first electrode, the material of which includes a third metal, the melting point of which is greater than that of the third metal.

4. The battery according to claim 3, characterized in that, The electrode also includes a second electrode, the material of which includes the second metal or a combination of the second metal and the first metal.

5. The battery according to claim 3 or 4, characterized in that, The first metal includes copper, the second metal includes nickel or a nickel-containing alloy, and the third metal includes aluminum.

6. The battery according to claim 4, characterized in that, The protective plate also includes: A second flame-retardant layer is disposed on the other side of the substrate.

7. The battery according to claim 6, characterized in that, The metal insulating layer includes a first insulating portion disposed at intervals, the orthographic projection of the first insulating portion on the electrical connection layer covering the electrical connection portion.

8. The battery according to claim 7, characterized in that, The metal insulating layer further includes a second insulating portion, the edge of which is flush with the edge of the circuit layer, and a through hole is provided on the second insulating portion, with the first insulating portion disposed within the through hole.

9. The battery according to claim 1, characterized in that, The electrode tab includes a bent portion, and the electrical connection portion is connected to the bent portion.

10. The battery according to claim 4, characterized in that, The first electrode and the second electrode are straight electrodes.

11. The battery according to claim 6, characterized in that, The hollowed-out areas on the first flame-retardant layer include: The region opposite to the first electrical connection portion in the first direction; The region opposite to the second electrical connection portion in the first direction; The region opposite to the first electrode tab in the first direction; and The region opposite to the second electrode in the first direction; The first direction is the direction perpendicular to the surface of the protective plate.

12. The battery according to claim 4, characterized in that, The first electrode tab and the first electrical connection part are welded by laser welding, and the second electrode tab and the second electrical connection part are welded by laser welding.

13. The battery according to claim 1, characterized in that, The solder joints between the electrode tab and the electrical connection portion form a preset pattern, which is one of the following: a circular array, a spiral array, multiple spaced straight lines, multiple spaced curves, or a spiral line.

14. The battery according to claim 1, characterized in that, The difference between the melting point of the second metal and the melting point of the first metal is less than or equal to 100°C.

15. An electrical appliance, characterized in that, The battery includes any one of claims 1 to 14.

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