CN218448041U - Battery and electronic equipment - Google Patents

Abstract

The utility model provides a battery and electronic equipment, the battery includes electric core, compound utmost point ear and plastic-aluminum membrane, and electric core setting is in the plastic-aluminum membrane, and one end setting in compound utmost point ear's the relative both ends is on electric core, and the other end is located outside the plastic-aluminum membrane, including compound heat-conducting layer between compound utmost point ear and the plastic-aluminum membrane. Like this, buckle the plastic-aluminum membrane and form a casing that has the holding chamber to carry out the banding in the junction of casing, with the leakproofness that promotes the plastic-aluminum membrane, electric core setting is in the holding chamber, and compound utmost point ear one end sets up on electric core, and the other end passes the banding and extends to the holding extraluminal. Through being provided with compound heat-conducting layer in the banding position to absorb the inside heat of electric core and shift the heat to between compound utmost point ear and the plastic-aluminum membrane when the battery is unusual fast, the pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature, thereby realizes the opening, and electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery.

Description

Battery and electronic equipment

Technical Field

The utility model relates to a battery technology field especially relates to a battery and electronic equipment.

Background

Lithium ion batteries are rapidly developed and applied in large scale, and the safety of the batteries is more and more concerned by people. At present, the thermal safety of the battery cell is generally improved by optimizing a chemical system, such as an anode, a cathode, a separator or an electrolyte, but the electrochemical performance of the battery cell is greatly influenced or the energy density is greatly sacrificed, so that the performance of the battery is reduced. Particularly in the quick-charging battery, the amorphous carbon coating amount of the quick-charging battery is large, so that the thermal stability of graphite is reduced, and the thermal stability of the battery is further reduced.

It can be seen that the battery in the prior art has the problem of low safety.

SUMMERY OF THE UTILITY MODEL

An embodiment of the utility model provides a battery and electronic equipment to solve the lower problem of battery security among the prior art.

The embodiment of the utility model provides a battery, including electric core, compound utmost point ear and plastic-aluminum membrane, electric core sets up in the plastic-aluminum membrane, one end in the relative both ends of compound utmost point ear sets up on the electric core, the other end is located outside the plastic-aluminum membrane;

the composite tab comprises a tab body, and a composite heat conduction layer is arranged between the tab body and the aluminum plastic film.

Optionally, the composite heat conducting layer comprises silicon carbide, expanded graphite and paraffin wax which are mixed.

Optionally, the composite heat conduction layer is disposed on two opposite side surfaces of the tab body.

Optionally, the composite tab further comprises polypropylene layers, and the polypropylene layers are arranged on two opposite side surfaces of the tab body;

the composite heat conduction layer is arranged between the tab body and the polypropylene layer, and/or the composite heat conduction layer is arranged on one side of the polypropylene layer, which is far away from the tab body;

or the polypropylene layer and the composite heat conduction layer are arranged on two side faces, back to back, of the tab body in a mixed mode.

Optionally, the composite heat conductive layer comprises a first sub-composite heat conductive layer and a second sub-composite heat conductive layer;

the aluminum-plastic film comprises an upper film shell and a lower film shell, and the upper film shell, the polypropylene layer on the first side of the tab body, the polypropylene layer on the second side of the tab body and the lower film shell are matched to form a sealed edge;

at least one of the upper film shell and the polypropylene layer on the first side of the tab body and the tab body is provided with the first sub-composite heat conduction layer; and/or

At least one of the lower membrane shell and the polypropylene layer on the second side of the tab body, and the polypropylene layer on the second side of the tab body and the tab body is provided with the second sub-composite heat conduction layer.

Optionally, the upper film shell comprises a first substrate layer, a first barrier layer and a first sealing layer which are sequentially arranged from outside to inside, the lower film shell comprises a second substrate layer, a second barrier layer and a second sealing layer which are sequentially arranged from outside to inside, and the first sealing layer and the second sealing layer are oppositely arranged on two opposite sides of the composite tab;

at least one of the first substrate layer and the first barrier layer, the first barrier layer and the first sealing layer and the tab body is provided with the first sub-composite heat conduction layer; and/or

At least one of the second substrate layer and the second barrier layer, the second barrier layer and the second sealing layer, and the second sealing layer and the tab body is provided with the second sub-composite heat conduction layer.

Optionally, the composite heat conduction layer further includes a third sub-composite heat conduction layer, and the third sub-composite heat conduction layer is disposed on one side of the first substrate layer and/or the second substrate layer, which is far away from the composite tab.

Optionally, the first substrate layer, the first barrier layer and the first sealing layer are fixed through a first bonding layer;

the second substrate layer, the second barrier layer and the second sealing layer are fixed through a second bonding layer.

Optionally, the tensile force between the composite tab and the aluminum-plastic film is less than or equal to 7N.

The embodiment of the utility model provides an electronic equipment is still provided, including foretell battery.

The embodiment of the utility model provides an in, buckle the plastic-aluminum membrane and form a casing that has the holding chamber to carry out the banding in the junction of casing, with the leakproofness that promotes the plastic-aluminum membrane, electric core sets up in the holding chamber, and compound utmost point ear one end sets up on electric core, and the other end passes the banding and extends to the holding chamber outsidely. Through being provided with compound heat-conducting layer in the banding position to absorb the inside heat of electric core and shift the heat to between compound utmost point ear and the plastic-aluminum membrane when the battery is unusual fast, pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature, thereby realizes the opening, and electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 is one of schematic structural diagrams of a composite tab of a battery according to an embodiment of the present invention;

fig. 2 is a second schematic structural view of a composite tab of a battery according to an embodiment of the present invention;

fig. 3 is one of the schematic structural diagrams of the aluminum plastic film of the battery provided by the embodiment of the present invention;

fig. 4 is a second schematic structural diagram of an aluminum plastic film of a battery according to an embodiment of the present invention;

fig. 5 is a third schematic structural diagram of an aluminum plastic film of a battery according to an embodiment of the present invention;

fig. 6 is a fourth schematic structural view of an aluminum plastic film of a battery according to an embodiment of the present invention;

fig. 7 is a fifth schematic structural view of an aluminum-plastic film of a battery according to an embodiment of the present invention;

fig. 8 is a sixth schematic structural view of an aluminum-plastic film of a battery according to an embodiment of the present invention;

fig. 9 is a seventh schematic structural view of an aluminum plastic film of a battery according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The terms "first," "second," and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be understood that the structures so used are interchangeable under appropriate circumstances such that embodiments of the invention can be practiced in sequences other than those illustrated or described herein, and the terms "first," "second," and the like are generally used herein in a generic sense without limitation to the number of terms, e.g., the first term can be one, or more than one. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

The embodiment of the utility model provides a battery, as shown in fig. 1 to 9, comprising an electric core, a composite tab and an aluminum plastic film, wherein the electric core is arranged in the aluminum plastic film, one end of the two opposite ends of the composite tab is arranged on the electric core, and the other end is positioned outside the aluminum plastic film;

the composite tab comprises a tab body 10, and a composite heat conduction layer 30 is arranged between the tab body 10 and the aluminum plastic film.

In this embodiment, buckle the plastic-aluminum membrane and form a casing that has the holding chamber to carry out the banding in the junction of casing, with the leakproofness that promotes the plastic-aluminum membrane, electric core setting is in the holding chamber, and compound utmost point ear one end sets up on electric core, and the other end passes the banding and extends to the holding extraluminal. Through being provided with compound heat-conducting layer 30 in the banding position to absorb the inside heat of electric core and shift the heat to between utmost point ear body 10 and the plastic-aluminum membrane when the battery is unusual fast, the pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature, thereby realizes the opening, and electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery.

The composite heat conducting layer 30 is formed by mixing silicon carbide, expanded graphite and paraffin.

The preparation method of the composite heat conduction layer 30 may be: firstly, stacking expanded graphite and paraffin in a beaker in layers, and drying for 2 hours at 100 ℃; followed by stirring at 80 ℃ for 30 minutes; and adding silicon carbide, stirring for 20 minutes at 80 ℃, and cooling to room temperature to obtain the composite heat conduction material. The composite heat conducting material can be formed into the composite heat conducting layer 30 by means of coating. The composite heat conduction layer 30 can be coated on the surface of the tab body 10 and/or on the aluminum-plastic film.

In some alternative embodiments, the composite heat conduction layer 30 may be disposed on two opposite sides of the tab body 10 to form a composite tab, so as to improve the effect of the tab body 10 on improving the thermal stability of the battery through the composite heat conduction layer 30.

The tab body 10 can be an aluminum metal conductor with the length, width and thickness of 18mm, 6mm and 0.1mm respectively, silicon carbide, expanded graphite and paraffin are used for obtaining a composite heat conduction material according to the above mode, and the composite heat conduction material is coated on the two side faces of the tab body 10 opposite to each other, so that the composite heat conduction layer 30 is arranged between the tab body 10 at the edge sealing position and the upper and lower aluminum plastic films. The tension between the composite tab and the aluminum plastic film at high temperature is reduced, so that the thermal stability of the battery is improved, the situations of short circuit, even explosion and the like of the battery are reduced, and the safety of the battery is improved.

The composite tab may further include a polypropylene layer 40 (i.e., a PP layer), and the polypropylene layer 40 may be disposed on two opposite sides of the tab body 10;

the composite heat conduction layer 30 can be arranged between the tab body 10 and the polypropylene layer 40, and/or the composite heat conduction layer 30 can be arranged on the side of the polypropylene layer 40 away from the tab body 10;

or the polypropylene layer 40 and the composite heat conduction layer 30 are arranged on two opposite sides of the tab body 10 in a mixed manner.

In some alternative embodiments, as shown in fig. 1, the composite heat conduction layer 30 is coated on two opposite side surfaces of the tab body 10, so that the composite heat conduction layer 30 is disposed between the tab body 10 at the edge sealing position and the upper and lower aluminum-plastic films, and then the composite heat conduction layer 30 is coated with the polypropylene layers 40 respectively to form a composite tab; and/or the presence of a gas in the atmosphere,

as shown in fig. 2, a polypropylene layer 40 may also be provided between the tab body 10 and the composite heat conductive layer 30. The polypropylene layer 40 can be a polypropylene film with the thickness, width and height of 0.08mm, 12mm and 4.5mm respectively, the polypropylene layer 40 is coated on two opposite sides of the tab body 10, and then the composite heat conduction layer 30 is coated on the polypropylene layer 40 respectively to form the composite tab. Make all be provided with compound heat-conducting layer 30 between utmost point ear body 10 and the upper and lower two-layer plastic-aluminum membrane of banding position to absorb the inside heat of electric core and shift the heat to between utmost point ear body 10 and the plastic-aluminum membrane through the compound heat-conducting layer 30 of the both sides of utmost point ear body 10 when the battery is unusual, reduced the pulling force between compound utmost point ear and the plastic-aluminum membrane.

In other alternative embodiments, the polypropylene layer 40 and the composite heat conducting layer 30 are arranged on two opposite sides of the tab body 10 in a mixed manner. In other words, the composite heat conducting layer 30 and the polypropylene layer 40 can be coated on both sides of the tab body 10 by co-extrusion to form a composite tab. Like this, through the inside heat of electric core of the quick absorption of the compound heat-conducting layer 30 of the both sides of utmost point ear body 10 when the battery is unusual and shift the heat to between utmost point ear body 10 and the plastic-aluminum membrane, the pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature to realize the opening, with higher speed electrolyte volatilizees in the holding chamber, cuts off the inside ion channel of electric core, and then promotes the security of battery.

Specifically, the composite heat conductive layer 30 may include a first sub-composite heat conductive layer 301 and a second sub-composite heat conductive layer;

the aluminum plastic film can comprise an upper film shell 21 and a lower film shell, wherein the upper film shell 21, the polypropylene layer on the first side of the tab body 10, the polypropylene layer on the second side of the tab body 10 and the lower film shell are matched to form an edge sealing;

at least one of the upper film shell 21 and the polypropylene layer on the first side of the tab body 10 and the tab body 10 is provided with a first sub-composite heat conduction layer 301; and/or

At least one of the lower membrane shell and the polypropylene layer at the second side of the tab body 10 and the tab body 10 is provided with a second sub-composite heat conduction layer.

Like this, cooperate at last membrane shell 21 and lower membrane shell and form a casing that has the holding chamber, and at the junction of last membrane shell 21 and lower membrane shell and the polypropylene layer hot melt of utmost point ear body 10 back of the body both sides mutually, in order to form the banding, the electric core sets up in the holding chamber, compound utmost point ear one end sets up on the electric core, the other end passes the banding and extends to the holding extravagant, and set up first compound heat-conducting layer 301 of son between utmost point ear body 10 and last membrane shell 21, and/or, set up the compound heat-conducting layer of second between utmost point ear body 10 and lower membrane shell, can make the banding include in proper order go up membrane shell 21, first compound heat-conducting layer 301 of son, utmost point ear body 10, the compound heat-conducting layer of second and lower membrane shell. The first sub-composite heat conduction layer 301 and the second sub-composite heat conduction layer can rapidly absorb the heat inside the battery core when the battery is abnormal, the heat is transferred to the space between the tab body 10 and the aluminum plastic film, the tension between the composite tab and the upper film shell 21 is reduced at high temperature, and the tension between the composite tab and the lower film shell is reduced, so that the opening is formed in the edge sealing position, the electrolyte is volatilized in the acceleration holding cavity, the ion channel inside the battery core is cut off, and the safety of the battery is further improved.

Optionally, as shown in fig. 3 to 9, the upper film shell 21 includes a first substrate layer 211, a first barrier layer 212, and a first sealing layer 213, which are sequentially arranged from outside to inside, and the lower film shell includes a second substrate layer, a second barrier layer, and a second sealing layer, which are sequentially arranged from outside to inside, and the first sealing layer 213 and the second sealing layer are oppositely arranged on two opposite sides of the tab body 10;

at least one of the first substrate layer 211 and the first barrier layer 212, the first barrier layer 212 and the first sealing layer 213, and the first sealing layer 213 and the tab body 10 is provided with a first sub-composite heat conduction layer 301; and/or

At least one of the second substrate layer and the second barrier layer, the second barrier layer and the second sealing layer, and the second sealing layer and the tab body 10 is provided with a second sub-composite heat conduction layer.

The first sub-composite heat conduction layer 301 may be disposed between the first sealing layer 213 and the tab body 10, and the second sub-composite heat conduction layer may be disposed between the second sealing layer and the tab body 10, so that the composite heat conduction layer 30 is disposed between the tab body 10 and the upper and lower aluminum-plastic films. The tension between the composite tab and the aluminum plastic film at high temperature is reduced, so that the thermal stability of the battery is improved, the situations of short circuit, even explosion and the like of the battery are reduced, and the safety of the battery is improved.

The first sub-composite thermal conductive layer 301 may also be disposed between the first barrier layer 212 and the first encapsulation layer 213; and/or, first sub-composite heat conduction layer 301 can also be arranged between first substrate layer 211 and first barrier layer 212 to improve the thermal stability of the battery, and the pulling force between the composite tab and upper membrane shell 21 obviously drops at high temperature, so as to realize opening, accelerate the volatilization of electrolyte in the accommodating cavity, cut off the ion channel inside the battery core, and further improve the safety of the battery. And/or the presence of a gas in the atmosphere,

the second sub-composite heat conduction layer can be further arranged between the second barrier layer and the second sealing layer; and/or, the sub-compound heat-conducting layer of second can also set up between second substrate layer and second barrier layer to improve the thermal stability of battery, compound utmost point ear and the lower tensile force between the membrane shell obviously descend under high temperature, thereby realize the opening, electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery.

The composite heat conduction layer 30 further includes a third sub-composite heat conduction layer 303, and the third sub-composite heat conduction layer 303 is disposed on one side of the first substrate layer 211 and/or the second substrate layer, which is far away from the composite tab. The thermal stability of the battery is further improved, the tension between the composite tab and the aluminum plastic film is reduced at high temperature, and the safety of the battery is improved.

The preparation of the positive electrode sheet can be described as follows:

mixing the positive active material, the first conductive agent and the first binder according to a certain proportion, adding N-methyl pyrrolidone, stirring and dispersing to prepare positive slurry. In the positive electrode slurry, the solid content contained 96.5wt% of Lithium Cobaltate (LCO), 1.5wt% of conductive carbon black, and 2wt% of polyvinylidene fluoride (PVDF). And coating the positive slurry on a positive current collector by coating equipment (double-sided coating), drying, slitting and flaking to prepare the positive pole piece.

Wherein, the positive active material can be at least one of lithium cobaltate, lithium iron phosphate, lithium nickel cobalt manganese oxide and lithium nickel cobalt aluminate;

the first conductive agent can be at least one of conductive graphite, ultrafine graphite, acetylene black, conductive carbon black SP, superconducting carbon black, carbon nano tubes and conductive carbon fibers;

the first binder is at least one selected from polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethylcellulose, styrene butadiene rubber, polyurethane, polyvinyl alcohol, polyvinylidene fluoride and vinylidene fluoride-fluorinated olefin copolymer.

The preparation of the negative electrode sheet can be described as follows:

mixing the negative electrode active material, the second conductive agent, the second binder and the thickening agent according to a certain proportion, adding deionized water, stirring and dispersing to prepare negative electrode slurry. The solid components in the negative electrode slurry comprise 96.9% of artificial graphite, 0.5% of conductive carbon black, 1.3% of sodium carboxymethylcellulose (CMC) and 1.3% of Styrene Butadiene Rubber (SBR), and then the negative electrode slurry is coated on a negative electrode current collector (double-sided coating), and the negative electrode pole piece is obtained through drying, slitting and sheet making.

Wherein, the negative active material can be at least one of artificial graphite, natural graphite, silicon and lithium titanate;

the second conductive agent can be at least one of conductive graphite, ultrafine graphite, acetylene black, conductive carbon black SP, superconducting carbon black, carbon nano tubes and conductive carbon fibers;

the second binder is at least one selected from polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethylcellulose, styrene butadiene rubber, polyurethane, polyvinyl alcohol, polyvinylidene fluoride and vinylidene fluoride-fluorinated olefin copolymer.

The preparation of the composite heat conduction layer 30 and the high-safety composite tab can be described as follows:

composite heat conductive layer 30: firstly, stacking expanded graphite and paraffin in a beaker in layers, and drying for 2 hours at 100 ℃; followed by stirring at 80 ℃ for 30 minutes; and adding silicon carbide, stirring for 20 minutes at 80 ℃, and cooling to room temperature to obtain the composite heat conduction material. The composite heat conducting material can be formed into the composite heat conducting layer 30 by means of coating.

High-safety composite tab: and coating the composite heat conduction layer 30 on two opposite side surfaces of the tab body 10, so that the composite heat conduction layers 30 are arranged between the tab body 10 at the edge sealing position and the upper and lower aluminum-plastic films, and then respectively coating the polypropylene layers 40 on the composite heat conduction layers 30 to form the composite tab. The tab body 10 may be an aluminum metal conductor with a length, a width and a thickness of 18mm, 6mm and 0.1mm, respectively, and the polypropylene layer 40 may be a polypropylene film with a thickness, a width and a height of 0.08mm, 12mm and 4.5mm, respectively.

The preparation of the battery can be described as follows:

the positive plate, the negative plate, the diaphragm, the tab body 10, the composite heat conduction layer 30 and the aluminum-plastic film are manufactured into the battery together, then the processes of liquid injection, aging, formation, sorting and the like are carried out, and finally the electrochemical performance and the safety performance (mainly needle abuse) of the battery are tested. The temperature of the preparation environment of the electrode material is kept between 20 and 30 ℃, and the humidity is less than or equal to 40 percent RH.

The preparation of the electrode material uses equipment including: the device comprises a stirrer, a coating machine, a roller press, a splitting machine, a pelleter, an ultrasonic spot welding machine, a top side sealing machine, an ink-jet printer, a film sticking machine, a liquid injection machine, a formation cabinet, a cold press, a separation cabinet, a vacuum oven and the like.

The battery produced in the above manner was designated as example 1-1, and example 1-2 and comparative example 1-1 were set simultaneously.

Embodiment 1-2 differs from embodiment 1-1 in that the composite heat conductive layer 30 is located outside the polypropylene layer 40 of the tab body 10, i.e., the polypropylene layer 40 is also disposed between the tab body 10 and the composite heat conductive layer 30.

Comparative example 1-1 differs from example 1-1 in that the composite tab of comparative example 1 was prepared by a conventional process, in other words, no composite heat conductive layer 30 was provided in comparative example 1-1.

The batteries of examples 1-1, 1-2 and 1-1 were subjected to an oven temperature test and a positive electrode sheet peel force test, respectively.

The lithium ion batteries of the above examples and comparative examples were subjected to an oven temperature test, which was as follows: firstly, charging the battery to an upper limit voltage of +30mV (0.02C cutoff) at 0.2C, and testing the initial state of the battery, including voltage, internal resistance, thickness and the like; then the battery is put into an oven and heated at the initial temperature of 25 plus or minus 3 ℃, the temperature rise rate is 5 plus or minus 2 ℃, the temperature rises to 130 plus or minus 2 ℃, and the test is finished after the temperature is kept for 60 min. The pass criteria were: the battery core does not catch fire or explode.

The results of the oven temperature test of the batteries of examples 1-1, 1-2 and comparative examples 1-1 are shown in the following table 1, respectively:

TABLE 1

As can be seen from the results in table 1, comparative example 1-1 is poor in safety and cannot satisfy the safety performance requirements of the lithium ion battery. And through being provided with compound heat-conducting layer 30 in the banding position to absorb the inside heat of electric core and shift the heat to between compound utmost point ear (positive compound utmost point ear or negative compound utmost point ear) and the plastic-aluminum membrane when the battery is unusual fast, the pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature, thereby realizes the opening, and electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery. Under the circumstances of pulling force less than or equal to 7N between compound utmost point ear and the plastic-aluminum membrane, the utility model discloses the furnace temperature through rate of embodiment 1-1 to embodiment 1-2 all is higher than comparative example 1-1 to lithium ion battery's security performance has effectively been promoted.

In the preferred embodiment 1-1, the composite heat conducting layer 30 is disposed on the surface close to the two sides of the tab body 10, so that the furnace temperature passing rate is higher under the condition that the tensile force between the composite tab and the aluminum plastic film is less than or equal to 5N, and the embodiment 1-1 can be specifically selected in practical application.

The preparation of the aluminum plastic film can be described as follows:

in the aluminum plastic film (i.e. the upper film shell 21 and the film shell), the substrate layers (the first substrate layer 211 and the second substrate layer) can be nylon casting film protective layers, and the thickness of a single layer can be 15 μm; the barrier layers (first barrier layer 212 and second barrier layer) may be aluminum layers, and the single layer thickness may be 20 μm; the sealing layers (the first sealing layer 213 and the second sealing layer) may be polypropylene PP cast film heat sealing layers, and the single layer thickness may be 20 μm, wherein at least one of between the first substrate layer 211 and the first barrier layer 212, between the first barrier layer 212 and the first sealing layer 213, and between the first sealing layer 213 and the tab body 10 is provided with the first sub-composite heat conduction layer 301; and/or at least one of the second substrate layer and the second barrier layer, the second barrier layer and the second sealing layer, and the second sealing layer and the tab body 10 is provided with a second sub-composite heat conduction layer. The thickness of each of the first sub-composite heat conductive layer 301 and the second sub-composite heat conductive layer may be 10 μm.

The first base material layer 211, the first barrier layer 212, and the first sealing layer 213 are fixed to each other by a first adhesive layer 214; the second substrate layer, the second barrier layer and the second sealing layer are fixed through a second bonding layer. The first adhesive layer 214 and the second adhesive layer may be made of the same material, may be made of acrylic resin, and may have a single-layer thickness of 1 μm. Curing for 1-4 days at the temperature of 44-80 ℃ to obtain the aluminum-plastic film so as to improve the stability of the aluminum-plastic film.

The first sub-composite heat conduction layer 301, the second sub-composite heat conduction layer and the third sub-composite heat conduction layer 303 are prepared by the same method. Firstly, stacking expanded graphite and paraffin in a beaker in layers, and drying for 2 hours at 100 ℃; followed by stirring at 80 ℃ for 30 minutes; and adding silicon carbide, stirring for 20 minutes at 80 ℃, and cooling to room temperature to obtain the composite heat conduction material. The composite heat conducting material can be formed into the composite heat conducting layer 30 by means of coating.

The first sub-composite heat conduction layer 301 is arranged at least one of between the first substrate layer 211 and the first barrier layer 212, between the first barrier layer 212 and the first sealing layer 213, and between the first sealing layer 213 and the tab body 10; the second sub-composite heat conduction layer is arranged at least one of the position between the second substrate layer and the second barrier layer, the position between the second barrier layer and the second sealing layer and the position between the second sealing layer and the tab body 10; the third sub-composite heat conduction layer 303 is arranged on one side of the first substrate layer 211 and/or the second substrate layer far away from the composite tab.

Examples 2-1 to 2-4 and comparative example 2-1 were arranged according to the difference in the arrangement positions of the composite heat conductive layer 30 (i.e., the first sub-composite heat conductive layer 301, the second sub-composite heat conductive layer, and the third sub-composite heat conductive layer 303) in the aluminum plastic film. The positions of disposing the composite heat conductive layer 30 in examples 2-1 to 2-4 are shown in fig. 3 to 6, respectively.

In example 2-1, as shown in fig. 3, the first base material layer 211 was a nylon casting film protective layer having a thickness of 15 μm; the first barrier layer 212 is an aluminum layer with a thickness of 20 μm; the first sealing layer 213 is a polypropylene PP cast film heat sealing layer, the thickness of which may be 20 μm, the thickness of the first sub-composite heat conduction layer 301 is 10 μm, the first sub-composite heat conduction layer 301 is disposed between the first sealing layer 213 and the tab body 10, the first substrate layer 211, the first barrier layer 212 and the first sealing layer 213 are fixed by the first adhesive layer 214, the first adhesive layer 214 is acrylic resin, and the thickness of which is 1 μm. Curing the mixture at the temperature of between 44 and 80 ℃ for 1 to 4 days to obtain the upper membrane shell 21. The same mode makes lower membrane shell, goes up membrane shell 21 and lower membrane shell and cooperatees and forms a casing that has the holding chamber to carry out the banding in the junction of last membrane shell 21 and lower membrane shell, electric core setting in the holding chamber, compound utmost point ear one end sets up on electric core, and the other end passes the banding and extends to the holding extramural, forms the lithium cell including compound heat-conducting layer 30.

Example 2-2 was provided, and as shown in fig. 4, example 2-2 differs from example 2-1 in that the third sub-composite heat conduction layer 303 was provided on the side of the first substrate layer 211 away from the composite tab.

Example 2-3 is provided, and as shown in fig. 5, the example 2-3 is different from the above example 2-1 in that the first sub-composite heat conduction layer 301 is arranged between the first sealing layer 213 and the tab body 10, and the third sub-composite heat conduction layer 303 is arranged on the side of the first substrate layer 211 far away from the composite tab.

Embodiment 2-4 is provided, and as shown in fig. 6, embodiment 2-4 is different from embodiment 2-1 described above in that the first sub-composite heat conduction layer 301 is provided between the first sealing layer 213 and the tab body 10, and between the first barrier layer 212 and the first sealing layer 213.

Meanwhile, a comparative example 2-1 is arranged, and the comparative example 2-1 is the same as the conventional aluminum plastic film process, namely, the composite heat conduction layer 30 is not arranged.

The batteries of examples 1-1, 1-2 and 1-1 were subjected to an oven temperature test and a positive electrode sheet peel force test, respectively.

The lithium ion batteries of the above examples and comparative examples were subjected to an oven temperature test, which was as follows: firstly, charging the battery to an upper limit voltage of +30mV (0.02C cutoff) at 0.2C, and testing the initial state of the battery, including voltage, internal resistance, thickness and the like; then the battery is put into an oven and heated at the initial temperature of 25 plus or minus 3 ℃, the temperature rise rate is 5 plus or minus 2 ℃, the temperature rises to 130 plus or minus 2 ℃, and the test is finished after the temperature is kept for 60 min. The pass criteria were: the battery core does not catch fire or explode.

The results of the oven temperature test of the batteries of examples 2-1 to 2-4 and comparative example 2-1, respectively, are shown in the following table 2:

TABLE 2

As can be seen from the results in Table 2, comparative example 2-1 is poor in safety and cannot satisfy the safety performance requirements of the lithium ion battery. And through being provided with compound heat-conducting layer 30 in banding position to absorb the inside heat of electric core and shift the heat to between compound utmost point ear (positive compound utmost point ear or negative pole) and the plastic-aluminum membrane when the battery is unusual fast, the pulling force between compound utmost point ear and the plastic-aluminum membrane obviously descends under high temperature, thereby realizes the opening, and electrolyte volatilizees in the holding chamber with higher speed, cuts off the inside ion channel of electric core, and then promotes the security of battery. Under the condition that the tension between the composite tab and the aluminum-plastic film is less than or equal to 5N, the safety performance of the lithium ion battery can be effectively improved.

Although the safety of the embodiment 2-1 is equivalent to that of the embodiment 2-3, the thickness of the aluminum-plastic film is larger in the embodiment 2-3 because the composite heat conduction layer 30 is added, according to the following energy density calculation formula:

the larger the thickness of the battery cell is, the lower the energy density of the same capacity is, and embodiment 2-1 may be specifically selected in practical application.

The embodiment of the utility model provides an electronic equipment is still provided, including foretell battery.

The electronic device may be a notebook computer, a smart phone, or the like, and is not limited herein. The implementation manner of the embodiment of the battery is also suitable for the embodiment of the electronic device, and can achieve the same technical effect, which is not described herein again.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element. Furthermore, it should be noted that the scope of the methods and apparatus of the embodiments of the present invention is not limited to performing functions in the order discussed, but may include performing functions in a substantially simultaneous manner or in a reverse order based on the recited functions, e.g., the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many forms without departing from the spirit and scope of the present invention.

Claims (9)

1. A battery is characterized by comprising an electric core, a composite tab and an aluminum plastic film, wherein the electric core is arranged in the aluminum plastic film, one end of two opposite ends of the composite tab is arranged on the electric core, and the other end of the composite tab is positioned outside the aluminum plastic film;

the composite tab comprises a tab body, and a composite heat conduction layer is arranged between the tab body and the aluminum-plastic film.

2. The battery of claim 1, wherein the composite heat conductive layer is disposed on opposite sides of the tab body.

3. The battery of claim 2 wherein the composite tab further comprises polypropylene layers disposed on opposite sides of the tab body;

the composite heat conduction layer is arranged between the tab body and the polypropylene layer, and/or the composite heat conduction layer is arranged on one side of the polypropylene layer, which is far away from the tab body;

or the polypropylene layer and the composite heat conduction layer are arranged on two side faces, back to back, of the tab body in a mixed mode.

4. The battery of claim 3, wherein the composite thermally conductive layer comprises a first sub-composite thermally conductive layer and a second sub-composite thermally conductive layer;

the aluminum-plastic film comprises an upper film shell and a lower film shell, and the upper film shell, the polypropylene layer on the first side of the tab body, the polypropylene layer on the second side of the tab body and the lower film shell are matched to form a sealed edge;

at least one of the upper film shell and the polypropylene layer on the first side of the tab body and the tab body is provided with the first sub-composite heat conduction layer; and/or

At least one of the lower membrane shell and the polypropylene layer on the second side of the tab body, and the polypropylene layer on the second side of the tab body and the tab body is provided with the second sub-composite heat conduction layer.

5. The battery of claim 4, wherein the upper film shell comprises a first substrate layer, a first barrier layer and a first sealing layer which are arranged in sequence from outside to inside, the lower film shell comprises a second substrate layer, a second barrier layer and a second sealing layer which are arranged in sequence from outside to inside, and the first sealing layer and the second sealing layer are oppositely arranged on two opposite sides of the composite tab;

at least one of the first substrate layer and the first barrier layer, the first barrier layer and the first sealing layer and the tab body is provided with the first sub-composite heat conduction layer; and/or

At least one of the second substrate layer and the second barrier layer, the second barrier layer and the second sealing layer, and the second sealing layer and the tab body is provided with the second sub-composite heat conduction layer.

6. The cell of claim 5 wherein the composite heat conductive layer further comprises a third sub-composite heat conductive layer disposed on a side of the first substrate layer and/or the second substrate layer distal from the composite tab.

7. The cell of claim 5 wherein the first substrate layer, the first barrier layer, and the first sealing layer are secured together by a first adhesive layer;

the second substrate layer, the second barrier layer and the second sealing layer are fixed through a second bonding layer.

8. The battery of claim 1, wherein the tensile force between the composite tab and the aluminum plastic film is 7N or less.

9. An electronic device characterized by comprising the battery according to any one of claims 1 to 8.

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