ELECTROCHEMICAL APPARATUS AND ELECTRONIC APPARATUS

An electrochemical apparatus includes a housing, an electrode assembly disposed inside the housing, a first tab group, and a first adapting piece electrically connected to the first tab group and extending out from the housing. The electrode assembly is configured to be a winding structure including a first electrode plate. The first tab group includes M first tabs connected to the first electrode plate. A thickness direction of the electrode assembly is defined as a first direction. In the first direction, the electrode assembly includes N layers of the first electrode plate, N being greater than M. The M first tabs are each connected to the first electrode plate. A plane passing through a winding center axis of the electrode assembly and perpendicular to the first direction is defined as a winding center plane. The M first tabs are disposed on two sides of the winding center plane.

TECHNICAL FIELD

This application relates to the field of energy storage technologies, and in particular, to an electrochemical apparatus and an electronic apparatus including such electrochemical apparatus.

BACKGROUND

With the popularity of consumer electronic products such as notebook computers, mobile phones, handheld game consoles, tablet computers, mobile power supplies, drones and electric cars, requirements for electrochemical apparatuses (for example, lithium-ion batteries) are increasingly stringent. However, it is hard for an electrochemical apparatus to have both good high-rate charge-discharge performance and good safety performance.

SUMMARY

In view of the deficiency in the prior art, it is necessary to propose an electrochemical apparatus.

It is also necessary to provide an electronic apparatus including such electrochemical apparatus.

This application provides an electrochemical apparatus, including a housing, an electrode assembly disposed inside the housing, a first tab group, and an adapting piece electrically connected to the first tab group and extending out of the housing. The electrode assembly is configured to be a winding structure and includes a first electrode plate. The first tab group includes M first tabs, and the first tabs are connected to the electrode plate. A thickness direction of the electrode assembly is defined as a first direction. In the first direction, the electrode assembly includes N layers of the first electrode plate, N being greater than M. The M first tabs are each connected to the first electrode plate. A plane passing through a winding center axis of the electrode assembly and perpendicular to the first direction is defined as a winding center plane. In the first direction, the M first tabs are disposed on two sides of the winding center plane. The first tab group includes a first connecting portion connected to the first adapting piece and a second connecting portion connected to the first electrode plate, where the M first tabs are stacked to form the first connecting portion. Part of the first tabs at the second connecting portion are connected to a side of the first connecting portion facing the electrode assembly.

In this application, the number M of first tabs is set to be smaller than the layer number N of the first electrode plate, helping reduce difficulties of tab bending and welding, thereby simplifying a manufacturing process. In addition, the M first tabs are connected to M layers in the N layers of the first electrode plate respectively, and on the basis that the first tabs are disposed on the two sides of the winding center plane, the number M of first tabs may be changed as required. Therefore, internal resistance of the electrode plate may be adjusted to make the electrochemical apparatus meet the requirements of different charge-discharge rates. Furthermore, because part of the first tabs at the second connecting portion are connected to the side of the first connecting portion facing the electrode assembly, owing to a limiting function of that part of first tabs, the first connecting portion has a more stable position and is not apt to insert inversely into the electrode assembly. Therefore, contact short circuit due to a tab being inversely inserted may be alleviated, improving safety of the electrochemical apparatus.

In some possible embodiments, in the first direction, layers of the first electrode plate connected to the first tabs and layers of the first electrode plate not connected to any of the first tabs are alternately arranged. Compared with the electrochemical apparatus with one side of the winding center plane provided with a tab structure, the first electrode plate being alternately provided with the first tab makes part of the first tabs disposed on the side of the first connecting portion facing the electrode assembly, and because of the limiting function of that part of first tabs, risks of contact short circuit due to the first connecting portion being inversely inserted are reduced and safety is improved. Also, because the number of first tabs is the same as the number of first tabs of an electrochemical apparatus with tab structures disposed on one side of its winding center plane, the number of first tabs added to ensure safety is reduced, where the additional first tabs cause difficulties in tab bending and welding in the manufacturing process.

In some possible embodiments, the first connecting portion forms a U-shaped structure. The first connecting portion includes a first sub-portion, a second sub-portion, and a third sub-portion. The first sub-portion is connected to the first adapting piece, the second sub-portion is connected to the second connecting portion, and the third sub-portion is bent and connected between the first sub-portion and the second sub-portion. The first adapting piece is at least partly disposed inside a space delimited by the U-shaped structure.

In some possible embodiments, in the first direction, in the N layers of the first electrode plate, one outermost layer of the first electrode plate is connected to one of the first tabs, and another outermost layer of the first electrode plate is not connected to any of the first tabs.

In some possible embodiments, the electrochemical apparatus further includes a first bonding piece and a second bonding piece. The first bonding piece is bonded to a side of the first sub-portion facing opposite to the electrode assembly. The second bonding piece is bonded to a side of the second sub-portion facing opposite to the electrode assembly and to a side surface of the electrode assembly in the first direction. In the first direction, the first bonding piece is further disposed between two adjacent layers of the first electrode plate, and the second connecting portion is located between the first bonding piece and the second bonding piece. The first bonding piece and the second bonding piece may reduce risks of short circuit or electrolyte leakage caused by the housing being pierced by burrs and welding marks of the first connecting portion. The first bonding piece includes a bending portion disposed on a side of the second sub-portion facing the electrode assembly. The bending portion also has a limiting function on the first connecting portion, further reducing risks of contact short circuit due to the first connecting portion being inversely inserted.

In some possible embodiments, each layer of the first electrode plate disposed between the first bonding piece and the second bonding piece is connected to one of the first tabs. In this manner, the number of first tabs may be further increased to increase a charge-discharge rate of the electrochemical apparatus.

In some possible embodiments, the M first tabs are welded together to form a welding region at the second sub-portion. The bending portion is disposed on a side of the welding region facing the electrode assembly. Because the M first tabs are fixed at the welding region of the second sub-portion by welding, risks may be reduced that the first connecting portion is inversely inserted because the first tabs at the second sub-portion are separated from each other, further improving safety of the electrochemical apparatus.

In some possible embodiments, in the N layers of the first electrode plate, two outermost layers of the first electrode plate are each connected to one of the first tabs.

In some possible embodiments, the electrochemical apparatus further includes a first bonding piece and a second bonding piece. The first bonding piece is bonded to a side of the first sub-portion facing opposite to the electrode assembly and to a side surface of the electrode assembly in the first direction. The second bonding piece is bonded to the side of the second sub-portion facing opposite to the electrode assembly and to the other side surface of the electrode assembly in the first direction. In the first direction, the second connecting portion is located between the first bonding piece and the second bonding piece. The first bonding piece and the second bonding piece may reduce risks of short circuit or electrolyte leakage caused by the housing being pierced by burrs and welding marks of the first connecting portion.

In some possible embodiments, the M first tabs are welded together to form a welding region at the second sub-portion. Because the M first tabs are fixed at the welding region of the second sub-portion by welding, risks may be reduced that the first connecting portion is inversely inserted because the first tabs at the second sub-portion are separated from each other, further improving safety of the electrochemical apparatus.

In some possible embodiments, at least one of the first bonding piece or the second bonding piece is an insulating tape.

In some possible embodiments, the first electrode plate includes a first current collector and a first active material layer disposed on a surface of the first current collector. The first tab and the first current collector are integrally formed.

This application further provides an electronic apparatus including the electrochemical apparatus described above.

REFERENCE SIGNS OF MAIN COMPONENTS

This application will be further described with reference to the accompanying drawings in the following specific embodiments.

DETAILED DESCRIPTION

The technical solutions in the embodiments of this application are clearly described below in detail. Apparently, the described embodiments are some rather than all of the embodiments of this application. Unless otherwise defined, all technical and scientific terms used herein shall have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are merely intended to describe specific embodiments but not intended to constitute any limitation on this application.

The following describes the embodiments of this application in detail. However, this application may be embodied in many different forms and should not be construed as being limited to the illustrative embodiments set forth herein. Rather, these illustrative embodiments are provided so that this application may be conveyed to those skilled in the art thoroughly and in detail.

In addition, in the accompanying drawings, sizes or thicknesses of various components and layers may be exaggerated for brevity and clarity. Throughout the application, the same numerical values represent the same elements. 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 when an element A is referred to as being “connected to” an element B, the element A may be directly connected the element B or an intermediate element C may be present therebetween such that the element A and the element B are indirectly connected to each other.

Further, the use of “may” in describing embodiments of this application refers to “one or more embodiments of this application”.

The terminologies used herein are merely intended to describe specific embodiments but not intended to constitute any limitation on this application. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that the terms “comprise” or “include” and variations thereof, when used in this specification, specify the presence of stated features, numbers, steps, operations, elements, and/or components but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, and/or combinations thereof.

Spatial relation terms such as “above” may be used herein for ease of description to describe the relation between one element or feature and another element (multiple elements) or feature (multiple features) as illustrated in the drawings. It should be understood that spatial relation terms are intended to encompass different orientations of a device or an apparatus in use or operation in addition to the orientations depicted in the drawings. For example, if the device in the drawings is turned over, elements described as being “above” or “over” other elements or features would then be oriented “below” or “beneath” the other elements or features. Thus, the example term “above” may encompass both orientations of being above and below. It should be understood that although the terms first, second, third, or so on may be used herein to describe various elements, components, zones, layers, and/or portions, these elements, components, zones, layers, and/or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, a first element, component, region, layer, or portion discussed below may be referred to as a second element, component, region, layer, or portion without departing from the teachings of the illustrative embodiments.

Referring toFIG.1toFIG.3, an embodiment of this application provides an electrochemical apparatus100, including a housing10, an electrode assembly20, a first tab group30, a second tab group40, a first adapting piece50, and a second adapting piece60. The electrode assembly20, the first tab group30, and the second tab group40are disposed inside the housing10.

As shown inFIG.1, in some embodiments, the housing10may be a packing bag obtained through packaging using package film (for example, aluminum-plastic film), which means that the electrochemical apparatus100is a pouch cell. The housing10includes a body11for accommodating the electrode assembly20and a sealing edge12connected to the body11. In some other embodiments, the electrochemical apparatus100is not limited to a pouch cell, but may alternatively be a steel-shell cell or an aluminum-shell cell, which is not limited in this application.

As shown inFIG.2andFIG.3, the electrode assembly20includes a first electrode plate21, a second electrode plate22, and a separator23disposed between the first electrode plate21and the second electrode plate22. The separator23is configured to prevent direct contact between the first electrode plate21and the second electrode plate22, thereby reducing risks of short circuit of the electrode assembly20. As shown inFIG.2, the electrode assembly20is configured to be a winding structure, that is, the first electrode plate21, the separator23, and the second electrode plate22are stacked in order with the stack wound to form the electrode assembly20. The electrode assembly20has a winding center axis C perpendicular to the plane of paper. The winding direction D is a direction of rotating counterclockwise around the winding center axis C as shown inFIG.2.

The first electrode plate21includes a first current collector211and a first active material layer212disposed on the first current collector211. The second electrode plate22includes a second current collector221and a second active material layer222disposed on the second current collector221. In some embodiments, the first electrode plate21may be a negative electrode plate, and the second electrode plate22may be a positive electrode plate. The first current collector211may be, but is not limited to, a metal foil such as a copper foil or a nickel foil. The second current collector221may be, but is not limited to, a metal foil such as an aluminum foil or a nickel foil. In some other embodiments, the first electrode plate21may be a positive electrode plate, and the second electrode plate22may be a negative electrode plate.

The first tab group30includes M first tabs31(M is a natural number greater than 1), where the M first tabs31are connected to the first electrode plate21. Specifically, the M first tabs31are all connected to the first current collector211of the first electrode plate21. More specifically, the plurality of first tabs31may be integrally formed with the first current collector211(which means the first tabs31are formed by cutting the first current collector211). The first adapting piece50is electrically connected to the first tab group30and extends out of the housing10at the sealing edge12to connect an external component (not shown in the figure). The electrode assembly20further has a first direction D1and a second direction D2. The first direction D1is a thickness direction of the electrode assembly20. The second direction D2is a direction of the first tab31extending out of the first electrode plate21. For example, the second direction D2may be a length direction of the electrode assembly20.

As shown inFIG.2andFIG.4, the second tab group40includes a plurality of second tabs41, and the second tabs41and the first tabs31have opposite polarities. The plurality of second tabs41are connected to the second electrode plate22. Specifically, the plurality of second tabs41are connected to the second current collector221of the second electrode plate22. More specifically, the plurality of second tabs41may be integrally formed with the second current collector221. The second adapting piece60is electrically connected to the second tab group40and extends out of the housing10at the sealing edge12to connect an external component.

As shown inFIG.2andFIG.3, in the first direction D1, one layer of the first current collector211and the first active material layer212disposed on the surface of the first current collector211are defined as one layer of the first electrode plate21. Then, the electrode assembly20includes N layers of the first electrode plate21(N is a natural number greater than 1), N being greater than M. For simplicity,FIG.2andFIG.3may only illustratively show partial layers of the first electrode plate21in the electrode assembly20while the other layers of the first electrode plate21are omitted. Therefore, it can be understood that the actual number of layers of the first electrode plate21is not limited to that shown in drawings. Similarly, the layer number of the second electrode plate22is also not limited to that shown in the drawings. The M first tabs31are connected each to the first electrode plate21. In other words, the M first tabs31are connected to M layers in N layers of the first electrode plate21respectively, and in the N layers of the first electrode plate21, the other (N minus M) layers of the first electrode plate21are not connected to any of the first tabs31. A plane passing through the winding center axis C of the electrode assembly20and perpendicular to the first direction D1is defined as a winding center plane P. In the first direction D1, the M first tabs31are disposed on two sides of the winding center plane P.

Specifically, as shown inFIG.2, in the winding direction D, the electrode assembly20includes a first section201, a first bending section203, a second section202, and a second bending section204that are connected in sequence. In some embodiments, the first section201and the second section202may be flat and straight sections arranged in parallel. In some other embodiments, the first section201and the second section202may alternatively be bending sections. This is not limited in this application. The winding center plane P is located between the first section201and the second section202. Therefore, the M first tabs31being disposed on the two sides of the winding center plane P means that part of the M first tabs31are connected to the first electrode plate21at the first section201, and the other part of the M first tabs31are connected to the first electrode plate21at the second section202.

More specifically, when N/2<M<N, the M first tabs31may be distributed arbitrarily on the two sides of the winding center plane P. When 2≤M≤N/2, the number of first tabs31located on one side of the winding center plane P is greater than or equal to 1, and the number of first tabs31located on the other side of the winding center plane P is greater than or equal to 1.

As shown inFIG.3, the first tab group30includes a first connecting portion301and a second connecting portion302. The first connecting portion301is connected to the first adapting piece50, and the second connecting portion302is connected between the first electrode plate21and the first connecting portion301. The M first tabs31are stacked to form the first connecting portion301. In some embodiments, at least two of the M first tabs31are stacked in mutual contact, and may be regarded as a part of the first connecting portion301. Part of the first tabs31at the second connecting portion302are connected to a side of the first connecting portion301facing the electrode assembly20.

A structure of the second tab group40may be similar to that of the first tab group30, and therefore is not further described.

Straight-out tabs take up space at the head of the electrode assembly, reducing energy density of the electrochemical apparatus. Therefore, before being welded to the adapting piece, the tabs need to be bent. For an electrochemical apparatus having a half tab structure (each turn of the electrode plate is connected to only one tab; for example, only the first electrode plate at the first section of the electrochemical apparatus is connected to first tabs), when an adapting piece is required to be inserted into the housing to a preset position so as to be welded to a bent tab, the bent tab is apt to inversely insert towards the electrode assembly and into the electrode assembly under the action of the adapting piece, causing short circuit and even smoke and fire during subsequent use, thereby degrading use safety of the electrochemical apparatus. An electrochemical apparatus having a full tab structure (each layer of the electrode plate is connected to one tab) helps increase the charge-discharge rate, but also increases difficulties of tab bending and welding, making a manufacturing process more costly.

In this application, one turn means a turn of the electrode assembly20along the winding direction D starting from a point thereof as a starting end and reaching another point as a terminating end, where the terminating end, the starting end, and the center of the turn are in one straight line and the starting end is located between the terminating end and the center of the turn. One turn forms two layers, which means one turn of the first electrode plate21includes two layers of the first electrode plate21.

In this application, the number M of first tabs31is set to be smaller than the layer number N of the first electrode plate21, helping reduce difficulties of tab bending and welding, thereby simplifying a manufacturing process. In addition, the M first tabs31are connected to M layers in the N layers of the first electrode plate21respectively, where on the basis that the first tabs31are disposed on the two sides of the winding center plane P, the number M of first tabs31may be changed as required. Therefore, internal resistance of the electrode plate may be adjusted to make the electrochemical apparatus100meet the requirements of different charge-discharge rates. Furthermore, because part of the first tabs31at the second connecting portion302are connected to the side of the first connecting portion301facing the electrode assembly20, owing to a limiting function of that part of first tabs31, the first connecting portion301has a more stable position in the second direction D2and is not apt to inversely insert under the action of the first adapting piece50when the first adapting piece50is inserted into the housing10. Therefore, contact short circuit due to a tab being inversely inserted may be alleviated, improving safety of the electrochemical apparatus100. Furthermore, an insulating adhesive layer in the prior art disposed for preventing inversely inserted tabs from contacting an end surface of the electrode assembly may be saved to decrease the cost.

As shown inFIG.3, in some embodiments, the first connecting portion301forms a U-shaped structure. The first portion301includes a first sub-portion3011, a second sub-portion3012opposite to the first sub-portion3011, and a third sub-portion3013bent and connected between the first sub-portion3011and the second sub-portion3012. The first connecting portion3011is connected to the first adapting piece50, and the second connecting portion3012is connected to the second connecting portion302. The first connecting portion301delimits a space S with an opening facing the first adapting piece50. The first adapting piece50is at least partly disposed inside the space S delimited by the U-shaped structure, and may be fixed to the first sub-portion3011by welding.

As shown inFIG.3, furthermore, in some embodiments, in the first direction D1, layers of first electrode plate21connected to the first tabs31and layers of the first electrode plate21not connected to any of the first tabs31are alternately arranged. In other words, the number M of first tabs31is N/2 rounded to the nearest whole number, where the number of first tabs31is substantially the same as the number of first tabs of an electrochemical apparatus having a half tab structure. Compared with an electrochemical apparatus having a half tab structure, N layers of the first electrode plate21being alternatively provided with a first tab31makes part of the first tabs31disposed on the side of the first connecting portion301facing the electrode assembly20, and owing to the limiting function of that part of first tabs31, risks of contact short circuit due to the first connecting portion301being inversely inserted are reduced and safety is improved. Also, because the number of first tabs31is the same as the number of first tabs of an electrochemical apparatus having a half tab structure, the number of first tabs31added to ensure safety is reduced, where the additional first tabs cause difficulties in tab bending and welding in the manufacturing process.

Referring toFIG.5AandFIG.5B, in some other embodiments, the number M of first tabs31is greater than N/2, where the first tabs31may be connected to any M layers in the N layers of the electrode plate21. In other words, the number M of first tabs31may be increased as required. Therefore, compared with the case that layers of the first electrode plate21connected to the first tabs31and layers of the first electrode plate21not connected to any of the first tabs31are alternately arranged, this may further reduce internal resistance of the first electrode plate21, increasing the charge-discharge rate of the electrochemical apparatus100.

As shown inFIG.3, in some embodiments, in the N layers of the first electrode plate21, the two outermost layers of the first electrode plate21are each connected to one of the first tabs31. The electrochemical apparatus100further includes a first bonding piece70and a second bonding piece80. The first bonding piece70is bonded to a side of the first sub-portion3011facing opposite to the electrode assembly20and to a side surface20aof the electrode assembly20in the first direction D1. In some embodiments, the side surface20aof the electrode assembly20may be the first electrode plate21, or the separator23, or another bonding piece (not shown in the figure). The second bonding piece80is bonded to a side of the second sub-portion3012facing opposite to the electrode assembly20and to the other side surface20bof the electrode assembly20in the first direction D1. In some embodiments, the side surface20bof the electrode assembly20may be the first electrode plate21, or the separator23, or another bonding piece (not shown in the figure). In the first direction D1, the second connecting portion302is located between the first bonding piece70and the second bonding piece80. It can be understood that burrs may be produced when the first current collector211is cut to form the first tabs31, and welding marks may also be produced when the first connecting portion301and the first adapting piece50are welded. The foregoing burrs and welding marks may pierce the housing10, leading to short circuit or electrolyte leakage. Providing the first bonding piece70and the second bonding piece80may reduce risks of short circuit or electrolyte leakage caused by the housing10being pierced by burrs or welding marks of the first connecting portion301. The first bonding piece70and/or the second bonding piece80may be an insulating tape.

Further, in some embodiments, in the first direction D1, width of the first bonding piece70is greater than that of the first connecting portion301. In some embodiments, a difference in width between the first bonding piece70and the first connecting portion301is 1 mm to 50 mm. Further, in some embodiments, in the first direction D1, width of the second bonding piece80is greater than that of the first connecting portion301. In some embodiments, a difference in width between the second bonding piece80and the first connecting portion301is 1 mm to 50 mm. In some embodiments, in the second direction D2, length of the first bonding piece70bonded to the side surface20aof the electrode assembly20is not less than 1 mm, making the first bonding piece70stably bonded to the electrode assembly20. In some embodiments, in the second direction D2, length of the second bonding piece80bonded to the side surface20bof the electrode assembly20is not less than 1 mm, making the second bonding piece80stably bonded to the first electrode plate21. In some embodiments, in the second direction D2, length of the first bonding piece70beyond an edge of the electrode assembly20is not less than 2 mm, making the first bonding piece70stably bonded to the first connecting portion301. In some embodiments, in the second direction D2, length of the second bonding piece80beyond the edge of the electrode assembly20is not less than 2 mm, making the first bonding piece80stably bonded to the first connecting portion301. It can be understood that to fully decrease direct contact between the first electrode plate21and the second electrode plate22, in the second direction D2, an edge of the separator23exceeds edges of the first electrode plate21and the second electrode plate22. Therefore, in the second direction D2, the edge of the electrode assembly20is typically the edge of the separator23.

Referring toFIG.6, in some other embodiments, the M first tabs31may be welded together to form a welding region3014at the second sub-portion3012. It can be understood that if the M first tabs31are not fixed together at the first connecting portion301, when the first adapting piece50is inserted into the housing10, the first tabs31at the first connecting portion301are apt to separate from each other under the action of the first adapting piece50. In this application, because the M first tabs31are fixed at the welding region3014of the second sub-portion3012by welding, risks may be further reduced that the first connecting portion301is inversely inserted because the first tabs31(for example, the first tabs31on the right side in the first direction D1inFIG.6) at the second sub-portion3012are separated from each other, further improving safety of the electrochemical apparatus100. In some embodiments, the welding region3014may be disposed at an end of the second sub-portion3012close to the third sub-portion3013.

Referring toFIG.7AandFIG.7B, another embodiment of this application further provides an electrochemical apparatus200. The electrochemical apparatus200differs from the electrochemical apparatus100in that, in the first direction D1, in the N layers of the first electrode plate21, one outermost layer of the first electrode plate21is connected to one of the first tabs31, and another outermost layer of the first electrode plate21is not connected to any of the first tabs31.

In this case, the first bonding piece70is bonded to a side of the first sub-portion3011facing opposite to the electrode assembly20. In the first direction D1, the first bonding piece70is also disposed between two adjacent layers of the electrode plate. The second bonding piece80is bonded to a side of the second sub-portion3012facing opposite to the electrode assembly20and to a side surface20bof the electrode assembly20in the first direction D1. In the first direction D1, the second connecting portion302is located between the first bonding piece70and the second bonding piece80. In this case, the first bonding piece70and the second bonding piece80may also reduce risks of short circuit or electrolyte leakage caused by the housing10being pierced by burrs of the first connecting portion301. The first bonding piece70includes a bending portion71, where the bending portion71is disposed on a side of the second sub-portion3012facing the electrode assembly20. Therefore, the bending portion71also has a limiting function in a second direction D2on the first connecting portion301to further reduce the risk of the contact short circuit caused by the inverse insertion of the first connecting portion301. In addition, in the first direction D1, the first bonding piece70is also disposed between two adjacent layers of the electrode plate, reducing the thickness in the first direction D1and increasing energy density.

As shown inFIG.7B, furthermore, each layer of a first electrode plate21disposed between a first bonding piece70and a second bonding piece80is connected to one of the first tabs31. In this manner, the number of the first tab31may be further increased, increasing a charge-discharge rate of an electrochemical apparatus100.

In some embodiments, the M first tabs31are welded together to form a welding region3014at the second sub-portion3012, so that the risk may be reduced that the first connecting portion301is inversely inserted because the first tabs31of the second sub-portion3012are separated from each other. The bending portion71is disposed on a side of the welding region3014facing the electrode assembly20.

Referring toFIG.8, yet another embodiment of this application further provides an electrochemical apparatus300. The electrochemical apparatus300differs from the electrochemical apparatus100in that the first connecting portion301is not a U-shaped structure, but runs in the second direction D2as a whole. During manufacturing, it is only required to bend the first tab group30at a joint between the first connecting portion301and a second connecting portion302, and the first connecting portion301itself does not need to be bent, helping simplify the manufacturing process.

The electrochemical apparatus100,200, or300in this application includes all apparatuses capable of electrochemical reactions. The electrochemical apparatus100,200, or300includes all kinds of primary batteries, secondary batteries, fuel batteries, solar batteries, and capacitors (for example, super capacitors). Optionally, the electrochemical apparatus100,200, or300may be a secondary lithium battery, including a secondary lithium metal battery, a secondary lithium-ion battery, a secondary lithium polymer battery, and a secondary lithium-ion polymer battery.

Referring toFIG.9, an embodiment of this application further provides an electronic apparatus1. The electronic apparatus1includes the electrochemical apparatus100(or the electrochemical apparatus200or300). The electrochemical apparatus100,200, and300of this application are applicable to electronic apparatuses1in various fields. In an embodiment, the electronic apparatus1of this application may be, but is not limited to, a notebook computer, a pen-input computer, a mobile computer, an electronic book player, a portable telephone, a portable fax machine, a portable copier, a portable printer, a stereo headset, a video recorder, a liquid crystal display television, a portable cleaner, a portable CD player, a mini-disc, a transceiver, an electronic notebook, a calculator, a memory card, a portable recorder, a radio, a standby power source, a motor, an automobile, a motorcycle, a motorized bicycle, a bicycle, a lighting appliance, a toy, a game console, a timepiece, an electric tool, a flash lamp, a camera, a large household battery, a lithium-ion capacitor, or the like.

Finally, it should be noted that the foregoing embodiments are merely intended to describe the technical solutions of this application, but not to constitute any limitation. Although this application is described in detail with reference to preferred embodiments, persons of ordinary skill in the art should understand that modifications or equivalent replacements can be made to the technical solutions of this application, without departing from the scope of the technical solutions of this application.