CN216354364U - Battery cell, battery and electronic equipment - Google Patents

Abstract

The utility model provides an electric core, a battery and electronic equipment, wherein the electric core comprises a plurality of current collectors, lugs and connecting pieces, wherein the lugs are provided with first connecting holes; every the mass flow body includes body and protrusion the utmost point ear connecting portion of body, it is a plurality of pile up the setting after utmost point ear connecting portion buckle and form the joint portion, be equipped with the second connecting hole in the joint portion, the connecting piece passes first connecting hole with the second connecting hole will the joint portion with utmost point ear links to each other. The two metal layers of the composite current collector in the battery core can be conducted simultaneously.

Description

Battery cell, battery and electronic equipment

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery core, a battery and electronic equipment.

Background

The lithium ion battery has the characteristics of high energy density, high output power, small environmental pollution and the like, and is widely applied to electronic equipment such as electric automobiles, mobile phones, computers and the like.

When the lithium ion battery is subjected to abnormal conditions such as extrusion, collision, puncture and the like, accidents such as fire, explosion and the like are easily caused by self internal short circuit and heat generation. In order to improve the safety performance of the battery, in the prior art, the electric core of the battery usually adopts a composite current collector, the composite current collector comprises an insulating layer and two metal layers, the two metal layers are attached to two opposite sides of the insulating layer, and the insulating layer is usually made of a resin material with a melting point intersecting bottom. Thus, when abnormal heat is generated in the battery, the insulating layer melts, the electrode is damaged, and the current is cut off, so that the temperature rise in the battery can be inhibited, and the ignition and explosion of the battery can be prevented.

However, the problem that the metal layers on the two sides of the composite current collector cannot be conducted simultaneously is also easily caused, so that the internal resistance difference of each battery in a production line is large.

SUMMERY OF THE UTILITY MODEL

In view of the foregoing problems, embodiments of the present invention provide a battery cell, a battery, and an electronic device, wherein two metal layers of a composite current collector in the battery cell can be conducted simultaneously.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

a first aspect of the embodiments of the present invention provides an electrical core, which includes a plurality of current collectors, tabs, and a connecting piece, where the tabs are provided with first connection holes, and the connecting piece is a conductive piece; every the mass flow body includes body and protrusion the utmost point ear connecting portion of body, it is a plurality of pile up the setting after utmost point ear connecting portion buckle and form the joint portion, be equipped with the second connecting hole in the joint portion, the connecting piece passes first connecting hole with the second connecting hole will the joint portion with utmost point ear links to each other.

In some possible embodiments, the tab connection part includes a first connection section, a bent section, and a second connection section; the first connecting section is connected with the current collector, and two ends of the bending section are respectively connected with the first connecting section and the second connecting section; the first connecting section and the second connecting section are stacked, and the second connecting holes are formed in the first connecting section and the second connecting section.

In some possible embodiments, the current collector comprises an insulating layer and two metal layers, the two metal layers being disposed on opposite sides of the insulating layer; the inner wall surface of the first connecting hole and the inner wall surface of the second connecting hole are both in contact with the outer wall surface of the connecting piece.

In some possible embodiments, the outer wall surface of the connecting member is a concave-convex wall surface.

In some possible embodiments, the tabs include a positive tab and a negative tab; the plurality of current collectors are configured as a plurality of positive current collectors configured as a positive current collector assembly coupled to the positive tab via the connector and a plurality of negative current collectors configured as a negative current collector assembly coupled to the negative tab via the connector; and after bending, the tab connection part is arranged on the positive current collector assembly and/or the negative current collector assembly in a stacking manner.

In some possible embodiments, the positive current collector assembly is correspondingly provided with a plurality of the connectors; and/or a plurality of connecting pieces are correspondingly arranged on the negative current collector assembly.

In some possible embodiments, the cell further comprises a separator assembly comprising a plurality of separators disposed between adjacent positive and negative current collectors.

A second aspect of an embodiment of the present invention provides a battery, which includes a casing and the battery cell of the first aspect, wherein the plurality of current collectors are disposed in the casing, and the tabs extend to an outer side of the casing.

In some possible embodiments, the outer wall surface of the tab is coated with a tab glue layer, and the tab glue layer is connected with the casing in a sealing manner.

A third aspect of embodiments of the present invention provides an electronic device including the battery of the second aspect.

Compared with the prior art, the battery cell, the battery and the electronic equipment provided by the embodiment of the utility model have the following advantages:

through buckling and piling up the utmost point ear connecting portion and setting up, area of contact grow between utmost point ear connecting portion and the connecting piece, also can be so that every metal level of compound mass flow body all can be connected with the connecting piece electricity, and the internal resistance of each electric core can be maintained in predetermined stable range in producing the line.

In addition to the technical problems solved by the embodiments of the present invention, the technical features constituting the technical solutions, and the advantages brought by the technical features of the technical solutions described above, other technical problems that can be solved by the battery cell, the battery, and the electronic device provided by the embodiments of the present invention, other technical features included in the technical solutions, and advantages brought by the technical features will be further described in detail in the detailed description.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a battery according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of the battery cell in fig. 1;

fig. 3 is a schematic structural view of the current collector of fig. 2;

fig. 4 is a schematic view illustrating the connection between the positive current collector assembly and the positive tab in fig. 2.

Reference numerals:

1: a battery;

10: an electric core;

111: a positive current collector;

112: a negative current collector;

11 a: an insulating layer;

11 b: a metal layer;

11A: a body;

11B: a tab connecting part;

11B 1: a first connection section;

11B 2: bending the section;

11B 3: a second connection section;

121: a positive electrode tab;

122: a negative electrode tab;

13: a connecting member;

14: a diaphragm;

20: a housing;

21: and a tab glue layer.

Detailed Description

In order to make the aforementioned objects, features and advantages of the embodiments of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a few embodiments of the utility model, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the prior art, a situation that two metal layers of a composite current collector cannot be conducted with a tab at the same time may occur in a battery cell, so that the internal resistance of the battery cell is not within a preset range, and the internal resistance difference of each battery cell in a production line is large.

In view of this, the tab connection portion of the composite current collector is bent and stacked, so that the positions of the tab connection portion, which can be in conduction with the tabs, are increased. Like this, the two-layer metal level of each mass flow body all can switch on with utmost point ear, and the internal resistance of electric core can be in predetermineeing the within range, avoids appearing the great problem of the difference of each electric core internal resistance in producing the line.

Fig. 1 is a schematic structural diagram of a battery according to an embodiment of the present invention. Fig. 2 is a schematic structural diagram of the battery cell in fig. 1. Fig. 3 is a schematic structural view of the current collector in fig. 2. Fig. 4 is a schematic view illustrating the connection between the positive current collector assembly and the positive tab in fig. 2.

Referring to fig. 1 to 4, the present embodiment provides an electrical core 10, which includes a plurality of current collectors, for example, the number of the current collectors may be 2 to 100, the number of the positive current collectors 111 is 15, and the number of the negative current collectors 112 is 16. Each current collector includes a body 11A and a tab connection part 11B protruding from the body 11A. The body 11A may have a rectangular structure. Illustratively, the body 11A has a width of 1mm to 80mm, a length of 3mm to 20mm, and a thickness of 0.001 to 0.1 mm. The tab connection part 11B may be circular, rectangular, etc. Illustratively, the tab connecting part 11B has a length of 1mm to 80mm and a length of 5mm to 100 mm. The material of the tab connecting portion 11B is the same as that of the body 11A.

The plurality of current collectors are configured as a plurality of positive current collectors 111 and a plurality of negative current collectors 112, that is, the plurality of current collectors are divided into two parts, wherein one part of the current collectors is the positive current collector 111, the plurality of positive current collectors 111 is configured as a positive current collector assembly, the other part of the current collectors is the negative current collector 112, and the plurality of negative current collectors 112 is configured as a negative current collector assembly. When the battery cell 10 is assembled, the positive electrode current collectors 111 and the negative electrode current collectors 112 are alternately stacked in sequence.

In order to lead out current to the electronic device to be charged, the battery cell 10 includes a tab and a connecting member 13, and the connecting member 13 is a conductive member, and the material of the conductive member may be a metal member such as copper, aluminum, or a composite material member after copper plating. The tabs comprise a positive tab 121 and a negative tab 122; the positive current collector assembly is connected to the positive electrode tab 121 through the connector 13, and the negative current collector assembly is connected to the negative electrode tab 122 through the connector 13.

The current collector may be a metal member. In some possible embodiments, the current collector may also be a composite current collector, which includes an insulating layer 11a and two metal layers 11b, where the two metal layers 11b are disposed on two opposite sides of the insulating layer 11a, and the two metal layers 11b are not in conduction with each other. That is, the current collector has a multilayer composite structure, and the insulating layer 11a may be made of a thermoplastic resin material. Such as polyethylene, polypropylene, polystyrene, polyamide, and the like. The thickness may be 2 μm to 50 μm.

It can be understood that the battery core can simultaneously comprise a metal current collector and a composite current collector, and at the moment, the battery core is bent and stacked on the tab connection part 11B, so that the battery core can be only arranged on the composite current collector, and the manufacturing cost of the battery core is reduced.

When the composite current collector constitutes the positive electrode current collector 111, the material of the metal layer 11b may be aluminum, an aluminum alloy, titanium, stainless steel, nickel, or an alloy thereof. When the composite current collector constitutes the negative electrode current collector 112, the material of the metal layer 11b may be copper, nickel, stainless steel, paste, or an alloy thereof. The thickness of the metal layer 11b may be 2 μm to 50 μm.

It can be understood that both sides of the positive electrode current collector 111 and both sides of the negative electrode current collector 112 are coated with the active material layer, and the tab connection part 11B is not coated with the active material layer, so that the current collector has a five-layer structure and the tab connection part 11B has a three-layer structure.

Taking a lithium ion battery as an example, the active materials on both sides of the positive electrode current collector 111 may be lithium manganate, lithium cobaltate, lithium nickel cobalt manganate, etc. The active material on both sides of the negative electrode collector 112 may be graphite or carbon having a nearly graphite structure, or the like. The thickness of the active material layer may be 0.02mm to 2 mm.

The insulating layer 11a has a low melting point, and for example, the melting point thereof may be 150 ℃. Like this, when cell 10 leads to self internal short circuit because of receiving unusual circumstances such as extrusion, collision, or puncture, the temperature of cell 10 risees, and insulating layer 11a can be heated at first and melt to cut off short-circuit current, in order to avoid the too high accident such as the emergence of electric core 10's temperature, explosion.

The tab and the tab connecting portion 11B may be welded to the connecting member 13, respectively. In some possible embodiments, the tab is provided with a first connection hole, the tab connection part 11B is bent and then stacked to form a combination part, the combination part is provided with a second connection hole, the connection member 13 may be a fastener such as a rivet or a bolt, and the outer diameter of the connection member 13 may be 0.01mm to 5mm according to the structure of the connection member 13.

The connection members 13 are respectively provided at the positions of the positive and negative electrode tabs 121 and 122. The material of the connecting member 13 located at the positive electrode tab 121 may be aluminum, and the material of the connecting member 13 located at the negative electrode tab 122 may be copper.

The connecting member 13 passes through the first and second coupling holes to couple the coupling portion to the tab. At this time, the inner wall surface of the first connection hole and the outer wall surface of the connection member 13 and the inner wall surface of the second connection hole and the outer wall surface of the connection member 13 are in contact with each other, and thus the current collector and the tab can be electrically connected.

In some embodiments, the tab and the joint may be simultaneously interposed between both end portions of the connection member 13 to reduce contact resistance. When the joint is located on the positive current collector assembly, that is, the positive electrode tab 121 and the plurality of joints are stacked and clamped between both ends of the connecting member 13 located at the positive electrode tab 121, and when the joint is located on the negative current collector assembly, the negative electrode tab 122 and the plurality of joints are stacked and clamped between both ends of the connecting member 13 located at the negative electrode tab 122.

Of course, when the joints are simultaneously provided on the positive and negative current collector assemblies, the positive electrode tab 121 and the plurality of joints are stacked and clamped between both ends of the connection member 13 at the positive electrode tab 121, and the negative electrode tab 122 and the plurality of joints are stacked and clamped between both ends of the connection member 13 at the negative electrode tab 122.

Wherein, because utmost point ear connecting portion 11B piles up the setting after buckling, is equipped with two second connecting holes on the utmost point ear connecting portion 11B at least, and at this moment, every metal level 11B all has at least two positions that can switch on with connecting piece 13, that is to say, every metal level 11B all can switch on with connecting piece 13, and the internal resistance of electric core 10 can be located and predetermines the within range.

Meanwhile, each second connection hole can be electrically connected with the connecting piece 13, so that the connection area between the tab connection part 11B and the connecting piece 13 is increased, the contact resistance between the connecting piece 13 and the tab connection part 11B is reduced, the reduction of the internal resistance of the battery cell 10 is facilitated, and the charging and discharging speed of the battery cell 10 is increased.

The tab connection part 11B may be bent a plurality of times, for example, two, three or more times. In order to reduce the manufacturing cost, the tab connecting part 11B may be bent at one time, and specifically, the joint part includes a first connecting section 11B1, a bent section 11B2, and a second connecting section 11B 3; the first connecting section 11B1 is connected with a current collector, and two ends of the bending section 11B2 are respectively connected with the first connecting section 11B1 and the second connecting section 11B 3; the first connecting section 11B1 and the second connecting section 11B3 are stacked, and the first connecting section 11B1 and the second connecting section 11B3 are provided with second connecting holes.

Thus, the first connecting section 11B1 and the second connecting section 11B3 can be compressed by the connecting member 13. At this time, each metal layer 11b has two positions that can be conducted with the connecting member 13, that is, each metal layer 11b can be conducted with the connecting member 13, and the internal resistance of the battery cell 10 can be within a preset range.

In some possible embodiments, the outer wall surface of the connecting member 13 is a concave-convex wall surface. Illustratively, the connecting member 13 has a plurality of protruding structures arranged at intervals, so that the contact area between the two metal layers 11b and the connecting member 13 that can be conducted becomes larger, the two metal layers 11b are both connected to the connecting member 13, the internal resistance of the battery cell 10 can be maintained within a preset range, and a large difference in the internal resistance of each battery cell 10 in the production line is avoided.

Meanwhile, the contact resistance between the connecting piece 13 and the tab connecting portion 11B can be reduced, which is beneficial to reducing the internal resistance of the battery cell 10 and improving the charging and discharging speed of the battery cell 10.

In some possible embodiments, the concave-convex wall surface may be a thread structure, and the structure of the connecting member 13 is simple and low in cost.

In some possible embodiments, the positive electrode current collector assembly is correspondingly provided with a plurality of connecting members 13 (as shown in fig. 4), and the distance between two adjacent second connecting holes may be 0.1-10 mm. In this way, the stacking between the tab connection portions 11B corresponding to the positive current collector assembly is tight, so that the contact resistance between the positive current collector assembly and the connection member 13 can be reduced, the reduction of the internal resistance of the battery cell 10 is facilitated, and the charging and discharging speed of the battery cell 10 is increased. At this time, the corresponding connection member 13 of the negative current collector assembly may be one (not shown).

In some possible embodiments, the negative electrode current collector assembly is correspondingly provided with a plurality of connecting members 13, and the distance between two adjacent second connecting holes may be 0.1mm to 10mm (not shown). Like this, the stacking between a plurality of utmost point ear connecting portion 11B that the negative pole current collector subassembly corresponds is inseparabler, can reduce the contact resistance between negative pole current collector subassembly and the connecting piece 13, helps reducing the internal resistance of electric core 10, improves the charge-discharge speed of electric core 10. At this time, the positive electrode collector assembly may have one corresponding connection member 13.

In some possible embodiments, a plurality of connectors 13 (not shown) may be respectively disposed on the positive electrode current collector assembly and the negative electrode current collector assembly to reduce the internal resistance of the battery cell 10 and increase the charging and discharging speed of the battery cell 10.

In some possible embodiments, the battery cell 10 further includes a separator assembly including a plurality of separators 14, the separators 14 being disposed between adjacent positive and negative current collectors 111, 112.

When the battery cell 10 is assembled, the separator 14 is inserted between any adjacent positive current collector 111 and negative current collector 112 to prevent the positive current collector 111 and the negative current collector 112 from contacting each other and causing short circuit. It is understood that the outside of the battery cell 10 is the separator 14 to achieve insulation from the casing 20 of the battery 1. The separator 14 has a microporous structure, and allows ions (e.g., lithium ions) to freely pass therethrough, but does not allow electrons to pass therethrough.

The material of the separator 14 may be resin fiber, nonwoven fabric made of polyethylene or the like, which is well known to those skilled in the art. The thickness of the membrane 14 may be 0.02mm to 0.1 mm.

In some possible embodiments, the melting point of the separator 14 may be less than 200 ℃, so that when the battery cell 10 is short-circuited, the separator 14 may be deformed by heat to block the microporous structure and block ionic conduction.

The present embodiment also provides a battery 1, which includes a casing 20 and the above-mentioned battery core 10, wherein a plurality of current collectors are disposed in the casing 20, and tabs extend to the outside of the casing 20, that is, a positive tab 121 and a negative tab 122 both extend to the outside of the casing 20. The structure, function, and working principle of the battery cell 10 have been described in the above embodiments, and are not described herein again. By adopting the battery cell 10, the battery 1 can enable the two metal layers 11b of the composite current collector to be conducted, and the internal resistance of the battery 1 can be maintained within a preset range.

The casing 20 is a container-shaped structure and is used for encapsulating the battery cell 10. The material of the case 20 may be an aluminum-plastic film. In the assembly process of the battery 1, the tab connection portions 11B of the plurality of positive electrode current collectors 111 are all connected with the positive electrode tabs 121, the other ends of the positive electrode tabs 121 extend out of the outer side of the casing 20, the tab connection portions 11B of the plurality of negative electrode current collectors 112 are all connected with the negative electrode tabs 122, and the other ends of the negative electrode tabs 122 extend out of the outer side of the casing 20.

In some possible embodiments, the outer wall surfaces of the tabs are coated with tab glue layers 21, that is, the outer wall surfaces of the positive tab 121 and the negative tab 122 are coated with tab glue layers 21, and the tab glue layers 21 are hermetically connected with the casing 20. That is, the positive electrode tab 121 and the casing 20 and the negative electrode tab 122 and the casing 20 are sealed by the tab glue layer 21, so as to prevent the casing 20 from leaking.

The tab glue layer 21 may be made of Polyvinyl chloride (PVC), polypropylene (PP), and the like, and is fixed to the positive tab 121 and the negative tab 122 by hot melting.

The width of the tab glue layer 21 is greater than that of the tab, the width of the tab glue layer 21 can be 3mm-85mm, the length of the tab glue layer 21 is less than that of the tab, the length of the tab glue layer 21 can be 2mm-40mm, and the thickness of the tab glue layer 21 can be 0.01mm-2 mm.

The present embodiment provides an electronic apparatus including the above battery 1. The structure, function, and operation principle of the battery 1 are described in the above embodiments, and are not described herein again.

The electronic device may be a mobile terminal (e.g., a mobile phone, a computer, etc.), a wearable device (e.g., a watch), a medical device, a new energy automobile, etc. By adopting the battery 1, the two metal layers 11b of the composite current collector can be conducted, the internal resistance of the battery 1 is maintained within a preset range, and the power consumption of the electronic equipment is prevented from being abnormal.

The embodiments or implementation modes in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It should be noted that in the description of the present application, the terms of direction or positional relationship indicated by the terms "inside", "outside", and the like are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or member must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present application.

It should also be noted that, in the description of the present application, unless otherwise explicitly specified or limited, the terms "connected" and "connected" should be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; there may be communication between the interiors of the two members. The specific meaning of the above terms in the present application can be understood by those skilled in the art as the case may be.

In the description of the present specification, reference to the description of the terms "one embodiment", "some embodiments", "an illustrative embodiment", "an example", "a specific example", or "some examples", etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the utility model has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A battery core is characterized by comprising a plurality of current collectors, a plurality of lugs and a connecting piece, wherein the lugs are provided with first connecting holes, and the connecting piece is a conductive piece;

every the mass flow body includes body and protrusion the utmost point ear connecting portion of body, it is a plurality of pile up the setting after utmost point ear connecting portion buckle and form the joint portion, be equipped with the second connecting hole in the joint portion, the connecting piece passes first connecting hole with the second connecting hole will the joint portion with utmost point ear links to each other.

2. The cell of claim 1, wherein the bond comprises a first connection segment, a bend segment, and a second connection segment; the first connecting section is connected with the current collector, and two ends of the bending section are respectively connected with the first connecting section and the second connecting section;

the first connecting section and the second connecting section are stacked, and the second connecting holes are formed in the first connecting section and the second connecting section.

3. The electrical core of claim 1, wherein the current collector comprises an insulating layer and two metal layers, the two metal layers being disposed on opposite sides of the insulating layer;

the inner wall surface of the first connecting hole and the inner wall surface of the second connecting hole are both in contact with the outer wall surface of the connecting piece.

4. The cell of claim 3, wherein the outer wall surface of the connector is a concave-convex wall surface.

5. The electrical core of any of claims 1 to 4, wherein the tabs comprise a positive tab and a negative tab;

the plurality of current collectors are configured as a plurality of positive current collectors configured as a positive current collector assembly coupled to the positive tab via the connector and a plurality of negative current collectors configured as a negative current collector assembly coupled to the negative tab via the connector;

and after bending, the tab connection part is arranged on the positive current collector assembly and/or the negative current collector assembly in a stacking manner.

6. The battery cell of claim 5, wherein a plurality of the connecting pieces are correspondingly arranged on the positive current collector assembly; and/or a plurality of connecting pieces are correspondingly arranged on the negative current collector assembly.

7. The cell of claim 5, further comprising a separator assembly comprising a plurality of separators disposed between adjacent positive and negative current collectors.

8. A battery comprising a cell of any of claims 1-7 and a casing, wherein the plurality of current collectors are disposed within the casing, and wherein the tabs extend outside the casing.

9. The battery of claim 8, wherein the outer wall surfaces of the tabs are coated with tab adhesive layers, and the tab adhesive layers are hermetically connected with the case.

10. An electronic device characterized by comprising the battery of claim 8 or 9.

Images