CN111916816B

CN111916816B - Laminated composite battery

Info

Publication number: CN111916816B
Application number: CN202010617009.2A
Authority: CN
Inventors: 伍鹏; 李素丽
Original assignee: Zhuhai Cosmx Battery Co Ltd
Current assignee: Zhuhai Cosmx Battery Co Ltd
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2022-03-01
Anticipated expiration: 2040-06-30
Also published as: CN111916816A

Abstract

The embodiment of the invention provides a laminated composite battery, which comprises a lithium ion battery laminated unit and a super capacitor laminated unit, wherein the lithium ion battery laminated unit comprises a positive plate, a negative plate and a diaphragm which can be used for a lithium ion battery; the two outermost layers of the composite battery are selected from one of a positive plate with one side coated with a positive material and a negative plate with one side coated with a negative material; in each super capacitor lamination unit, the active material of the super capacitor positive electrode material is the same as that of the super capacitor negative electrode material. The composite battery has the advantages of both a lithium ion battery and a super capacitor, and has high power density.

Description

Laminated composite battery

Technical Field

The invention relates to the technical field of lithium ion batteries, in particular to a laminated composite battery.

Background

In recent years, with the rise and development of the fields of electric automobiles, electric bicycles, high-power starting and stopping equipment and the like, the demand for a power supply with high energy density and high power density is increasing. The lithium ion battery has the advantages of large specific energy, high working voltage, environmental friendliness, no memory effect and the like, but the power density of the lithium ion battery is usually only a fraction or even less than a tenth of that of a super capacitor battery, and the capacity utilization rate is lower at lower temperature.

On the contrary, the super capacitor battery has short charging and discharging time, and the charging time is 1 second to 10 minutes to reach more than 95 percent of the rated capacity; the ultralow temperature property is good, and the normal use temperature range is wide from minus 40 ℃ to plus 70 ℃; the high-current discharge capacity is strong, and the power density is as high as 300-10000W/Kg, which is equivalent to several times or even tens of times of that of a lithium ion battery. At present, the super capacitor is widely applied to the fields of large current, data backup, hybrid electric vehicles and the like. But at the same time, the energy density is not high, and is only a fraction or even a tenth of that of the lithium ion battery, which severely limits the application of the lithium ion battery in a plurality of fields with higher requirements on the energy density.

Therefore, a composite battery which has the advantages of a lithium ion battery and a super capacitor and has the advantages of high power and energy density, good rate characteristic, high cycle efficiency, long service life, low unit power cost and the like is developed, and the composite battery plays a vital role in the application and development of industry.

Disclosure of Invention

The invention aims to prepare a novel battery with the advantages of a lithium ion battery and a super capacitor.

The inventors have discovered through research that a combination of a positive electrode sheet for a lithium ion battery and a positive electrode sheet for a supercapacitor is used in combination with a negative electrode sheet to form a composite battery that can provide predetermined combinations of different lithium ion battery properties and supercapacitor properties. The combination of the positive plate for the lithium ion battery and the positive plate for the super capacitor can be adjusted through the simple quantity conversion of the positive plates for the lithium ion battery and the super capacitor, so that different mass energy densities (Wh/kg) and mass power densities (W/kg) can be generated in the composite battery, the composite battery can better adapt to different environments, the characteristics of high energy density of the lithium ion battery and high power density of the super capacitor are achieved, meanwhile, when the positive plate or the negative plate coated with the electrode material on one side is adopted as the outermost layer positive plate or the negative plate of the composite battery, the energy density can be improved, and when the symmetrical super capacitor is adopted, when the energy densities are the same, the power density is higher.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a laminated composite battery comprises a lithium ion battery lamination unit and a super capacitor lamination unit, wherein the lithium ion battery lamination unit comprises a positive plate, a negative plate and a diaphragm which can be used for a lithium ion battery; the two outermost layers of the composite battery are selected from one of a positive plate with one side coated with a positive material and a negative plate with one side coated with a negative material; in each super capacitor lamination unit, the active material of the super capacitor positive electrode material is the same as that of the super capacitor negative electrode material.

Further, the positive electrode sheet capable of being used for the supercapacitor is selected from the following positive electrode sheets:

the first positive plate comprises a first positive current collector and a super capacitor positive material arranged on the two side surfaces of the first positive current collector;

the third positive plate comprises a third positive current collector, a lithium ion battery positive electrode material arranged on a first surface of the third positive current collector, and a super capacitor positive electrode material arranged on a second surface, opposite to the first surface, of the third positive current collector;

and the fourth positive plate comprises a fourth positive current collector and a super capacitor positive material arranged on one side surface of the fourth positive current collector.

Further, the negative electrode sheet capable of being used for the supercapacitor is selected from the following negative electrode sheets:

the third negative plate comprises a third negative current collector and a supercapacitor negative material arranged on the two side surfaces of the third negative current collector;

the fourth negative plate comprises a fourth negative current collector and a supercapacitor negative material arranged on one side surface of the fourth negative current collector;

the eighth negative plate comprises an eighth negative current collector and a first negative material arranged on the first surface of the eighth negative current collector, and a second negative material arranged on the second surface, opposite to the first surface, of the eighth negative current collector, wherein the first negative material is selected from one of a bifunctional negative material and a lithium ion battery negative material, the second negative material is a super capacitor negative material, and the first negative material is different from the second negative material, and can adsorb/desorb lithium ions and can be used for embedding/desorbing lithium ions of the lithium ion battery.

Further, the positive electrode sheet coated with the positive electrode material on one side is selected from the following positive electrode sheets:

a fourth positive plate comprising a fourth positive current collector and a supercapacitor positive material disposed on a surface of one side of the fourth positive current collector;

and the fifth positive plate comprises a fifth positive current collector and a lithium ion battery positive electrode material arranged on the surface of one side of the fifth positive current collector.

Further, the negative electrode sheet having one side coated with the negative electrode material is selected from the following negative electrode sheets;

a second negative electrode tab including a second negative electrode current collector and a bifunctional negative electrode material provided on one side surface of the second negative electrode current collector, the bifunctional negative electrode material being capable of adsorbing/desorbing lithium ions and of inserting/extracting lithium ions of the lithium ion battery;

and the sixth negative plate comprises a sixth negative current collector and a lithium ion battery negative electrode material arranged on one side surface of the sixth negative current collector.

Further, the positive electrode sheet that can be used for a lithium ion battery is selected from the following positive electrode sheets:

the second positive plate comprises a second positive current collector and lithium ion battery positive materials arranged on two surfaces of the second positive current collector;

Further, the negative electrode sheet capable of being used in the lithium ion battery is selected from the following negative electrode sheets:

a first negative electrode tab including a first negative electrode current collector and a bifunctional negative electrode material disposed on both side surfaces of the first negative electrode current collector, the bifunctional negative electrode material being capable of adsorbing/desorbing lithium ions and of inserting/extracting lithium ions of the lithium ion battery;

the fifth negative plate comprises a fifth negative current collector and lithium ion battery negative materials arranged on the surfaces of the two sides of the fifth negative current collector;

the sixth negative plate comprises a sixth negative current collector and a lithium ion battery negative electrode material arranged on one side surface of the sixth negative current collector;

the first negative electrode material and the second negative electrode material are respectively selected from one of a bifunctional negative electrode material, a super capacitor negative electrode material and a lithium ion battery negative electrode material, and the first negative electrode material is different from the second negative electrode material, and the bifunctional negative electrode material can adsorb/desorb lithium ions and can be used for embedding/desorbing the lithium ions of the lithium ion battery.

Further, the composite battery comprises a first positive electrode tab, a second positive electrode tab and a negative electrode tab which are mutually independent; the positive plate capable of being used for the super capacitor lamination unit is connected with a first positive electrode tab; the positive plate which can be used for the lithium ion battery lamination unit is connected with a second positive electrode tab, and the negative plates of the super capacitor lamination unit and the lithium ion battery lamination unit are both connected with a negative electrode tab; when the composite battery comprises a third positive plate, the third positive plate is connected with the first positive electrode lug or the second positive electrode lug, and the third positive plate comprises a third positive current collector, a lithium ion battery positive electrode material arranged on the first surface of the third positive current collector and a super capacitor positive electrode material arranged on the second surface, opposite to the first surface, of the third positive current collector.

Further, first positive pole utmost point ear and the setting of the anodal utmost point ear of second are in compound battery's relative both sides, perhaps, first positive pole utmost point ear and the setting of the anodal utmost point ear of second are in the adjacent both sides of battery.

The laminated composite battery provided by the embodiment of the invention at least has the following beneficial effects:

(1) the composite battery provided by the embodiment of the invention has the advantages of high energy density, high average output voltage, high charging efficiency, low self-discharge efficiency, good safety performance, long cycle and service life and the like of the lithium ion battery, and also has the advantages of stable performance, short charging and discharging time, long cycle life, high power density and the like of the super capacitor.

(2) When the positive plate or the negative plate with the electrode material coated on one side is used as the outermost positive plate or the outermost negative plate of the composite battery, the energy density can be improved.

(3) Furthermore, when the symmetrical super capacitor is adopted, the power density is higher when the energy density is the same.

(4) Further, when the anode of the lithium ion battery and the anode of the super capacitor are respectively and independently connected with two anode tabs, the self-discharge effect of the composite battery in the prior art can be reduced. The composite battery in the prior art only has one positive electrode lug, and because of the serious self-discharge defect of the super capacitor, when the electric energy stored by the super capacitor is consumed due to self-discharge, because only one positive electrode lug is directly connected with the positive electrode of the lithium ion battery, at the moment, the electric energy stored by the lithium ion battery is continuously and weakly discharged through the super capacitor, and finally, the self-discharge effect of the whole composite battery is overlarge to influence normal use. And two mutually independent positive pole lugs are adopted, different charging systems and voltages can be selected for a positive pole for lithium ions of the composite battery and a positive pole for the super capacitor, so that the energy density and the power density of the composite battery can reach the compatibility which is difficult to realize in the prior art, the battery can reach the optimal performance, and different modes can be adopted to carry out power supply management on the lithium ion battery and the super capacitor according to actual needs, so that respective advantages can be better exerted, and the function can not be realized by the traditional single positive pole lug.

Drawings

Fig. 1 is a schematic structural diagram of a positive electrode tab for a supercapacitor according to an embodiment of the present invention, where (a) is a front view of the positive electrode tab for the supercapacitor, (b) and (c) are side views, 11 is a first positive electrode current collector, 12 is a fourth positive electrode current collector, and a positive electrode material of the supercapacitor is coated on a surface of the positive electrode current collector (hatched portion in the drawing).

Fig. 2 is a schematic structural diagram of a positive electrode sheet for a lithium ion battery according to an embodiment of the present invention, where (a) is a front view of the positive electrode sheet for a lithium ion battery, and (b) and (c) are side views, 21 is a second positive electrode current collector, 22 is a fifth positive electrode current collector, and a positive electrode material (shaded in the drawing) of the lithium ion battery is coated on a surface of the positive electrode current collector.

Fig. 3 is a schematic structural diagram of a positive electrode sheet for a lithium ion battery and a supercapacitor according to an embodiment of the present invention, where (a) is a first-direction front view of the positive electrode sheet, (b) is a side view, and (c) is a front view of the positive electrode sheet opposite to the first direction, 30 is a third positive current collector, a first surface 31 of the third positive current collector is coated with a lithium ion battery positive electrode material (hatched in the figure), and a second surface 32 of the third positive current collector is coated with a supercapacitor positive electrode material (hatched in the figure).

Fig. 4 is a schematic structural diagram of a compatible negative electrode sheet according to an embodiment of the present invention, where (a) is a front view of the compatible negative electrode sheet, (b) and (c) are side views, 41 is a first negative electrode collector, 42 is a second negative electrode collector, and the surface of the negative electrode collector is coated with a bifunctional negative electrode material (shaded in the drawing).

Fig. 5 is a schematic structural diagram of a negative electrode sheet for a supercapacitor according to an embodiment of the present invention, where (a) is a front view of the negative electrode sheet for a supercapacitor, and (b) and (c) are side views, 51 is a third negative electrode current collector, 52 is a fourth negative electrode current collector, and a negative electrode material for a supercapacitor is coated on a surface of the negative electrode current collector (hatched portion in the drawing).

Fig. 6 is a schematic structural diagram of a transition negative electrode sheet according to an embodiment of the present invention, where (a) is a first-direction front view of the negative electrode sheet, (b) is a side view, and (c) is a front view opposite to the first direction of the negative electrode sheet, 70 is a seventh negative electrode collector, a first surface 71 of the seventh negative electrode collector is coated with a negative electrode material of a lithium ion battery (shaded in the drawing), and a second surface 72 of the seventh negative electrode collector is coated with a negative electrode material of a supercapacitor (shaded in the drawing).

Fig. 7 is a schematic structural view of a composite battery containing a symmetrical supercapacitor according to an embodiment of the present invention, and (a) is a front view of the battery.

Fig. 8 is a schematic structural diagram of a composite battery containing an asymmetric supercapacitor according to an embodiment of the present invention, where (a) is a front view of the battery.

Fig. 9 is a schematic structural diagram of a hybrid battery including both asymmetric supercapacitors and symmetric supercapacitors according to an embodiment of the invention, where (a) is a front view of the battery.

Fig. 10 is a schematic view of a tab structure of a composite battery according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings. Those skilled in the art will appreciate that the present invention is not limited to the figures and examples described below. As used herein, the term "include" and its various variants are to be understood as open-ended terms, which mean "including, but not limited to. The terms "first", "second" and the like are used merely to indicate different technical features, and have no essential meaning.

< composite type Battery >

In one aspect of the present invention, a laminated composite battery according to an embodiment of the present invention includes a lithium ion battery lamination unit and a super capacitor lamination unit, where the lithium ion battery lamination unit includes a positive plate, a negative plate and a diaphragm that can be used for a lithium ion battery, and the super capacitor lamination unit includes a positive plate, a negative plate and a diaphragm that can be used for a super capacitor; the two outermost layers of the composite battery are selected from one of a positive plate with one side coated with a positive material and a negative plate with one side coated with a negative material; in each super capacitor lamination unit, the active material of the super capacitor positive electrode material is the same as that of the super capacitor negative electrode material.

In one aspect of the present invention, the positive electrode sheet that can be used for a supercapacitor is selected from the following positive electrode sheets:

In one aspect of the present invention, the negative electrode sheet capable of being used in a supercapacitor is selected from the following negative electrode sheets:

In one aspect of the present invention, the positive electrode sheet having one side coated with the positive electrode material is selected from the group consisting of:

In one aspect of the present invention, the negative electrode sheet having one side coated with the negative electrode material is selected from the group consisting of a negative electrode sheet;

In one aspect of the present invention, the positive electrode sheet that can be used in a lithium ion battery is selected from the following positive electrode sheets:

In one aspect of the present invention, the negative electrode sheet that can be used in a lithium ion battery is selected from the following negative electrode sheets:

In one aspect of the present invention, the composite battery includes a first positive electrode tab and a second positive electrode tab, which are independent of each other, and a negative electrode tab; the positive plate capable of being used for the super capacitor lamination unit is connected with a first positive electrode tab; the positive plate which can be used for the lithium ion battery lamination unit is connected with a second positive electrode tab, and the negative plates of the super capacitor lamination unit and the lithium ion battery lamination unit are both connected with a negative electrode tab; when the composite battery comprises a third positive plate, the third positive plate is connected with the first positive electrode lug or the second positive electrode lug, and the third positive plate comprises a third positive current collector, a lithium ion battery positive electrode material arranged on the first surface of the third positive current collector and a super capacitor positive electrode material arranged on the second surface, opposite to the first surface, of the third positive current collector.

In one aspect of the present invention, the first positive electrode tab and the second positive electrode tab are disposed on opposite sides of the composite battery, or the first positive electrode tab and the second positive electrode tab are disposed on adjacent sides of the battery.

< Positive electrode sheet for supercapacitor >

In one aspect of the invention, the laminated composite battery of the embodiment of the invention comprises a positive plate, wherein the positive plate comprises a first positive plate C1, the first positive plate C1 is a positive plate for a super capacitor, and the first positive plate C1 comprises a first positive current collector for the super capacitor and a super capacitor positive material arranged on two side surfaces of the first positive current collector.

Preferably, the positive electrode sheet according to the embodiment of the present invention further includes a fourth positive electrode sheet C2, the fourth positive electrode sheet C2 is a positive electrode sheet for a supercapacitor, and the fourth positive electrode sheet C2 includes a fourth positive electrode current collector for a supercapacitor and a supercapacitor positive electrode material disposed on one side surface of the fourth positive electrode current collector. Only one side of the fourth positive electrode tab C2 is provided with the positive electrode material of the supercapacitor, and the fourth positive electrode tab C2 may be used as the outermost positive electrode tab of the composite type battery.

As shown in fig. 1, a fourth positive electrode tab C2 for a supercapacitor, which is coated with a positive electrode material for a supercapacitor on one side surface of the fourth positive electrode current collector, is defined as C-mono (fig. 1 (b)); the first positive electrode tab C1 for a supercapacitor, which is coated with a supercapacitor positive electrode material on both side surfaces of the first positive electrode current collector for the supercapacitor, is defined as C-bis ((C) of fig. 1). The purpose of the arrangement of the first positive plate C1 and the fourth positive plate C2 for the super capacitor is to form a super capacitor positive and negative electrode pair with the adaptive negative plate F1, F2 or F3, so that the super capacitor lamination unit can store electric energy. Furthermore, C-mono and C-bis are primarily used to maximize the utilization of active materials in different configurations, with C-mono being primarily used in lamination units of outermost supercapacitors and C-bis being primarily used in lamination units of non-outermost supercapacitors.

In one embodiment, the first positive current collector and the fourth positive current collector for the supercapacitor are both selected from aluminum foil.

The super capacitor positive electrode material comprises a super capacitor positive electrode active material, a super capacitor positive electrode binder and a super capacitor positive electrode conductive agent.

In some embodiments, the compacted density of the first positive electrode tab and the fourth positive electrode tab for the supercapacitor is 0.5-4.3g/cm³。

In some embodiments, the positive active material for the supercapacitor accounts for 70-99% of the total mass of the positive material of the supercapacitor, the positive conductive agent for the supercapacitor accounts for 0.5-15% of the total mass of the positive material of the supercapacitor, and the positive binder for the supercapacitor accounts for 0.5-15% of the total mass of the positive material of the supercapacitor.

In some embodiments, the supercapacitor is positiveThe polar active substance is selected from active porous carbon material (one or more of active carbon powder, active carbon fiber, carbon aerogel, carbon nanotube, carbide derived carbon, graphite ring, graphene oxide, and graphene); metal oxides (e.g. RuO)₂、MnO₂、ZnO、PbO₂、WO₃、NiO、Co₃O₄、MoO₂Etc.); metal sulfides (e.g. MnS)₂、PbO₂、WS₃、NiS、MoS₂、TiS₂、FeS、FeS₂Etc.); mixed metal oxides (e.g. NiCo)₂O₄、ZnCo₂O₄、FeCo₂O₄、MnCo₂O₄、CoNi₂O₄、ZnNi₂O₄Etc.); mixed metal sulfides (e.g. NiCo)₂S₄、ZnCo₂S₄、FeCo₂S₄、MnCo₂S₄、CoNi₂S₄、ZnNi₂S₄Etc.); conductive polymers (e.g., poly (3-methyl-thiophene), polyaniline, polypyrrole, polyparaphenylene, polyacene, polythiophene, polyacetylene, and the like).

In some embodiments, the positive electrode binder for the supercapacitor may be a polymer material including, but not limited to, polyvinylidene fluoride and polyimide.

In some embodiments, the positive electrode conductive agent for a supercapacitor may be at least one of conductive carbon black, acetylene black, ketjen black, carbon nanotubes, and graphene.

< Positive electrode sheet for lithium ion Battery >

In an aspect of the present invention, the positive plate of the composite battery according to the embodiment of the present invention further includes a second positive plate L1, the second positive plate L1 is a positive plate for a lithium ion battery, and the second positive plate L1 includes a second positive current collector for a lithium ion battery and a lithium ion battery positive material disposed on two side surfaces of the second positive current collector for a lithium ion battery.

Preferably, the positive electrode sheet according to the embodiment of the present invention further includes a fifth positive electrode sheet L2, the fifth positive electrode sheet L2 is a positive electrode sheet for a lithium ion battery, and the fifth positive electrode sheet L2 includes a fifth positive electrode current collector for a lithium ion battery and a positive electrode material of the lithium ion battery disposed on one side surface of the fifth positive electrode current collector. Only one side of the fifth positive electrode sheet L2 is provided with a positive electrode material of the lithium ion battery, and the fifth positive electrode sheet L2 can be used as the outermost positive electrode sheet of the composite battery.

As shown in fig. 2, a fifth positive electrode sheet L2 for a lithium ion battery, which is coated with a positive electrode material for a lithium ion battery on a side surface of the fifth positive electrode current collector for a lithium ion battery, is defined as L-mono ((b) in fig. 2); the second positive electrode sheet L1 for a lithium ion battery, which is coated with a positive electrode material for a lithium ion battery on both side surfaces of the second positive electrode current collector for a lithium ion battery, is defined as L-bis ((c) in fig. 2). The second positive plate L1 and the fifth positive plate L2 for the lithium ion battery are arranged to form a positive and negative electrode pair of the lithium ion battery with the adaptive negative plates F1 and F2, so that lithium ions are inserted and removed in the charging and discharging processes of the lithium ion battery, and a lamination unit of the lithium ion battery is formed. Furthermore, L-mono and L-bis are primarily used to the greatest extent in different configurations, with L-mono being primarily used in lamination units of outermost lithium ion batteries and L-bis being primarily used in lamination units of non-outermost lithium ion batteries.

In one embodiment, the second positive electrode current collector and the fifth positive electrode current collector for a lithium ion battery are selected from aluminum foils.

The lithium ion battery positive electrode material comprises a positive electrode active material for a lithium ion battery, a positive electrode binder for the lithium ion battery and a positive electrode conductive agent for the lithium ion battery.

In some embodiments, the second positive electrode sheet and the fifth positive electrode sheet for the lithium ion battery each have a compacted density of 2 to 4.3g/cm³。

In some embodiments, the positive electrode active material for the lithium ion battery accounts for 75-99% of the total mass of the positive electrode material for the lithium ion battery, the positive electrode conductive agent for the lithium ion battery accounts for 0.5-15% of the total mass of the positive electrode material for the lithium ion battery, and the positive electrode binder for the lithium ion battery accounts for 0.5-10% of the total mass of the positive electrode material for the lithium ion battery.

In some embodiments, the lithium ion battery is usedThe positive electrode active material is selected from lithium iron phosphate (LiFePO)₄) Lithium nickel cobalt manganese oxide (Li)_zNi_xCo_yMn_1-x-yO₂Wherein z is more than or equal to 0.95 and less than or equal to 1.05, x>0，y>0，x+y<1) Lithium nickel cobalt aluminate (Li)_zNi_xCo_yAl_1-x-yO₂Wherein z is more than or equal to 0.95 and less than or equal to 1.05, x>0，y>0，0.8≤x+y<1) Lithium nickel cobalt oxide (LiNi)_xCo_yO₂Wherein x is>0，y>0, x + y ═ 1), lithium nickel titanium magnesium oxide (LiNi)_xTi_yMg_zO₂Wherein x is>0，y>0，z>0, x + y + z ═ 1), lithium nickel cobalt manganese aluminate (Li)_zNi_xCo_yMn_wAl_1-x-y-wO₂Wherein z is more than or equal to 0.95 and less than or equal to 1.05, x>0，y>0，w>0，0.8≤x+y+w<1) Lithium titanate (LiTiO)₂) Layered lithium manganate (LiMnO)₂) Lithium nickelate (Li)₂NiO₂) Spinel lithium manganate (LiMn)₂O₄) Lithium-rich manganese-based solid solution cathode material xLi₂MnO₃·(1-x)LiMO₂Wherein M is Ni/Co/Mn.

Illustratively, the nickel-cobalt-manganese ternary composite positive electrode material is LiNi_1/3Co_1/3Mn_1/3、LiNi_0.5Co_0.2Mn_0.3、LiNi_0.4Co_0.2Mn_0.4、LiNi_0.6Co_0.2Mn_0.2、LiNi_0.8Co_0.1Mn_0.1、LiNi_0.7Co_0.2Mn_0.1、LiNi_0.7Co_0.15Mn_0.15、LiNi_xCo_yMn_1-x-yO₂(wherein z is more than or equal to 0.95 and less than or equal to 1.05, x is more than or equal to 0.8 and less than or equal to 0.95, x is more than or equal to 0.03 and less than or equal to 0.2, and x + y<1) At least one of (1).

In some embodiments, the positive electrode binder for lithium ion batteries may be a polymeric material including, but not limited to, polyvinylidene fluoride and polyimide.

In some embodiments, the positive electrode conductive agent for a lithium ion battery may be at least one of conductive carbon black, acetylene black, ketjen black, carbon nanotubes, graphene oxide, and graphene.

< Positive electrode sheet for lithium ion Battery and supercapacitor >

In one aspect of the present invention, the positive electrode sheet further includes a third positive electrode sheet H, where the third positive electrode sheet H is a positive electrode sheet for a lithium ion battery and a supercapacitor, and includes a third positive electrode current collector for a lithium ion battery and a supercapacitor, a lithium ion battery positive electrode material disposed on a first surface of the third positive electrode current collector for the lithium ion battery and the supercapacitor, and a supercapacitor positive electrode material disposed on a second surface of the third positive electrode current collector for the lithium ion battery and the supercapacitor, the second surface being opposite to the first surface.

As shown in fig. 3, a third positive electrode sheet H for a lithium ion battery and a supercapacitor is formed by coating a lithium ion battery positive electrode material on a first surface of a third positive electrode current collector for a lithium ion battery and a supercapacitor, and coating a supercapacitor positive electrode material on a second surface opposite to the first surface; the third positive plate H for the lithium ion battery and the super capacitor can be used as a transition positive plate, one side of the third positive plate H for the lithium ion battery and the super capacitor can form a lithium ion battery lamination unit, and the other side of the third positive plate H for the lithium ion battery and the super capacitor can form a super capacitor lamination unit, so that transition of the lithium ion battery and the super capacitor is realized. The third positive plate can be connected with the first positive pole lug and the second positive pole lug, and when a plurality of third positive plates are arranged in the composite battery, the same positive pole lug can be connected, and different positive pole lugs can also be connected.

In one embodiment, the third current collector for the lithium ion battery and the supercapacitor is selected from aluminum foil.

Wherein, the definition of the lithium ion battery anode material is the same as above.

Wherein, the definition of the super capacitor anode material is the same as above.

< compatible negative electrode sheet >

In one aspect of the present invention, the negative electrode sheet of the composite type battery includes a first negative electrode sheet F1, and the first negative electrode sheet F1 includes a first negative electrode collector and a bifunctional negative electrode material disposed on both side surfaces of the first negative electrode collector. The difunctional cathode material can adsorb/desorb lithium ions and can be used for inserting/extracting lithium ions of a lithium ion battery. The bifunctional negative electrode material has dual characteristics, so that the first negative electrode piece can be used as a negative electrode piece of a supercapacitor and also can be used as a negative electrode piece of a lithium ion battery, namely the first negative electrode piece is a compatible negative electrode piece.

Preferably, the negative electrode sheet further comprises a second negative electrode sheet F2, and the second negative electrode sheet F2 comprises a second negative electrode collector and a bifunctional negative electrode material disposed on one side surface of the second negative electrode collector. Only one side of the second negative electrode sheet F2 is provided with the bifunctional negative electrode material, and the second negative electrode sheet F2 can be used as the outermost negative electrode sheet of the composite type battery. The second negative plate is also a compatible negative plate.

As shown in fig. 4, the second negative electrode tab F2 coated with the bifunctional negative electrode material on one side surface of the second negative electrode collector is defined as F2-mono ((b) in fig. 4) and the first negative electrode tab F1 coated with the bifunctional negative electrode material on both side surfaces of the first negative electrode collector is defined as F1-bis ((c) in fig. 4). The first negative plate F1 and the second negative plate F2 can be matched with the positive plates L1 and L2 for the lithium ion battery, the positive plates C1 and C2 for the super capacitor, or the positive plates H for the lithium ion battery and the super capacitor, and form a lithium ion battery lamination unit or a super capacitor lamination unit, so that when the composite battery is charged and discharged, the two modes of physical energy storage of the super capacitor and chemical energy storage of the lithium ion battery are realized.

In one embodiment, the first negative current collector and the second negative current collector are each selected from copper foils, such as electrolytic copper foils or rolled copper foils.

Wherein the bifunctional anode material comprises a first anode active material, a first anode binder, and a first anode conductive agent.

In some embodiments, the first negative electrode active material comprises 70-99% of the total mass of the bifunctional negative electrode material, the first negative electrode conductive agent comprises 0.5-15% of the total mass of the bifunctional negative electrode material, and the first negative electrode binder comprises 0.5-15% of the total mass of the bifunctional negative electrode material.

In some embodiments, the first negative electrode active material is any material capable of deintercalating metal ions such as lithium ions, for example, the first negative electrode active material may be one or more of graphite, a silicon material, a silicon-carbon composite material, a silicon-oxygen material, an alloy material, and a lithium-containing metal composite oxide material.

In some embodiments, the first negative electrode binder includes, but is not limited to, one or more of styrene-butadiene rubber, fluorine-based rubber, and ethylene propylene diene, hydroxymethyl cellulose.

In some embodiments, the first negative electrode conductive agent may be at least one of conductive carbon black, acetylene black, ketjen black, carbon nanotubes, and graphene.

< negative electrode sheet for supercapacitor >

In one aspect of the present invention, the negative electrode sheet includes a third negative electrode sheet F3, the third negative electrode sheet is a negative electrode sheet for a supercapacitor, and the third negative electrode sheet F3 includes a third negative electrode current collector and a supercapacitor negative electrode material disposed on both side surfaces of the third negative electrode current collector.

Preferably, the negative electrode sheet further comprises a fourth negative electrode sheet F4, the fourth negative electrode sheet is a negative electrode sheet for a supercapacitor, and the fourth negative electrode sheet F4 comprises a fourth negative electrode current collector and a supercapacitor negative electrode material arranged on one side surface of the fourth negative electrode current collector. Only one side of the fourth negative electrode sheet F4 is provided with the supercapacitor negative electrode material, and the fourth negative electrode sheet F4 can be used as the outermost negative electrode sheet of the composite type battery.

As shown in fig. 5, a fourth negative electrode tab F4 for a supercapacitor, which is coated with a supercapacitor negative electrode material on one side surface of the fourth negative electrode current collector, is defined as F4-mono (fig. 5 (b)); the third negative electrode tab F3 for the supercapacitor, which is coated with the supercapacitor negative electrode material on both side surfaces of the third negative electrode current collector, is defined as F3-bis ((c) of fig. 5). The third negative plate F3 and the fourth negative plate F4 can be matched with the positive plates C1 and C2 for the supercapacitor or the positive plates H for the lithium ion battery and the supercapacitor to form a supercapacitor laminated unit, and particularly, when the cathode materials of the supercapacitor of the third negative plate F3 and the fourth negative plate F4 and the cathode material of the supercapacitor of the positive plate for the supercapacitor are the same, a symmetrical supercapacitor laminated unit can be formed, and when the cathode materials of the supercapacitor of the third negative plate F3 and the fourth negative plate F4 and the cathode material of the supercapacitor of the positive plate for the supercapacitor are different but are all supercapacitor active materials, an asymmetrical supercapacitor laminated unit can be formed.

In one embodiment, the third and fourth negative current collectors are selected from copper foils, such as electrolytic copper foils or rolled copper foils.

In some embodiments, the supercapacitor negative electrode material includes a supercapacitor negative active material, a supercapacitor negative binder, and a supercapacitor negative conductive agent.

In some embodiments, the negative electrode active material for the supercapacitor accounts for 70-99% of the total mass of the negative electrode material for the supercapacitor, the negative electrode conductive agent for the supercapacitor accounts for 0.5-15% of the total mass of the negative electrode material for the supercapacitor, and the negative electrode binder for the supercapacitor accounts for 0.5-15% of the total mass of the negative electrode material for the supercapacitor.

In some embodiments, the negative active material for the supercapacitor is selected from activated porous carbon materials (one or more of activated carbon powder, activated carbon fiber, carbon aerogel, carbon nanotube, carbide-derived carbon, graphite ring, graphene oxide, graphene, etc.); metal oxides (e.g. RuO)₂、MnO₂、ZnO、PbO₂、WO₃、NiO、Co₃O₄、MoO₂Etc.); metal sulfides (e.g. MnS)₂、PbO₂、WS₃、NiS、MoS₂、TiS₂、FeS、FeS₂Etc.); mixed metal oxides (e.g. NiCo)₂O₄、ZnCo₂O₄、FeCo₂O₄、MnCo₂O₄、CoNi₂O₄、ZnNi₂O₄Etc.); mixed metal sulfides (e.g. NiCo)₂S₄、ZnCo₂S₄、FeCo₂S₄、MnCo₂S₄、CoNi₂S₄、ZnNi₂S₄Etc.); conductive polymers (e.g., poly (3-methyl-thiophene), polyaniline, polypyrrole, polyparaphenylene, polyacene, polythiophene, polyacetylene, and the like).

In some embodiments, the negative binder for the supercapacitor may be a polymeric material including, but not limited to, polyvinylidene fluoride and polyimide.

In some embodiments, the negative electrode conductive agent for a supercapacitor may be at least one of graphite, carbon black, acetylene black, ketjen black, carbon nanotubes, and graphene.

< negative electrode sheet for lithium ion Battery >

In one aspect of the present invention, the negative electrode sheet includes a fifth negative electrode sheet, the fifth negative electrode sheet is a negative electrode sheet for a lithium ion battery, and the fifth negative electrode sheet includes a fifth negative electrode current collector and lithium ion negative electrode materials disposed on two side surfaces of the fifth negative electrode current collector.

Preferably, the negative plate further comprises a sixth negative plate, the sixth negative plate is a negative plate for a lithium ion battery, and the sixth negative plate comprises a sixth negative current collector and a supercapacitor negative material arranged on the surface of one side of the sixth negative current collector. Only one side of the sixth negative plate is provided with the negative electrode material of the lithium ion battery, and the sixth negative plate can be used as the outermost negative plate of the composite battery.

The fifth negative plate and the sixth negative plate are respectively the same in structure as the third negative plate and the fourth negative plate, and only the negative electrode materials are different. The fifth negative plate and the sixth negative plate can be matched with the positive plates L1 and L2 for the lithium ion battery or the positive plates H for the lithium ion battery and the super capacitor to form a lithium ion battery structural unit. The lithium ion battery negative electrode material has various types, and a person skilled in the art can select a suitable lithium ion battery negative electrode material in the prior art according to actual needs.

In one embodiment, the fifth negative electrode current collector and the sixth negative electrode current collector are each selected from copper foils, for example, electrolytic copper foils or rolled copper foils.

< negative electrode sheet for transition >

In an aspect of the present invention, the negative electrode sheet further includes a seventh negative electrode sheet F5, the seventh negative electrode sheet is a transition negative electrode sheet, the seventh negative electrode sheet F5 includes a seventh negative electrode current collector and a first negative electrode material disposed on a first surface of the seventh negative electrode current collector, and a second negative electrode material disposed on a second surface of the seventh negative electrode current collector opposite to the first surface, the first negative electrode material and the second negative electrode material are both selected from one of the above-mentioned bifunctional negative electrode material, a supercapacitor negative electrode material, and a lithium ion battery negative electrode material, and the first negative electrode material is different from the second negative electrode material.

Illustratively, as shown in fig. 6, a lithium ion battery negative electrode material is coated on a first surface of the fifth negative electrode current collector, and a supercapacitor negative electrode material is coated on a second surface of the fifth negative electrode current collector opposite to the first surface. The seventh negative electrode tab F5 may be fitted to the positive electrode tabs L1 and L2 for lithium ion batteries and the positive electrode tab H for lithium ion batteries and supercapacitors, respectively, on the first surface side, and may be fitted to the positive electrode tabs C1 and C2, respectively, on the second surface side. Therefore, the seventh negative plate F5 can be used as a transition negative plate, one side of the seventh negative plate F5 forms a lithium ion battery lamination unit, and the other side of the seventh negative plate F5 forms a super capacitor lamination unit, so that when the composite battery is charged and discharged, two modes of physical energy storage of the super capacitor and chemical energy storage of the lithium ion battery are realized.

Wherein, the seventh negative current collector is selected from copper foil, such as electrolytic copper foil or rolled copper foil.

Wherein the bifunctional negative electrode material, the supercapacitor negative electrode material and the lithium ion battery negative electrode material are defined as above.

In another aspect of the present invention, the negative electrode sheet further includes an eighth negative electrode sheet, the eighth negative electrode sheet is another transition negative electrode sheet, the eighth negative electrode sheet includes an eighth negative electrode current collector and a first negative electrode material disposed on a first surface of the eighth negative electrode current collector, and a second negative electrode material on a second surface of the eighth negative electrode current collector opposite to the first surface, the first negative electrode material is selected from one of a bifunctional negative electrode material and a negative electrode material of a lithium ion battery, the second negative electrode material is a supercapacitor negative electrode material, the first negative electrode material is different from the second negative electrode material, and the bifunctional negative electrode material is capable of adsorbing/desorbing lithium ions and is capable of inserting/extracting lithium ions from the lithium ion battery.

< lithium ion Battery lamination Unit >

Illustratively, in an aspect of the present invention, the positive electrode sheet L1 for a lithium ion battery, the separator and the compatible negative electrode sheet F1 may form a lithium ion battery lamination unit a1, and the lithium ion battery lamination unit a1 includes a lithium ion battery cell structure Y1 formed by a positive electrode material for a lithium ion battery, the separator and a negative electrode material for a lithium ion battery. The compatible negative electrode tab F1 may also be replaced with a negative electrode tab for a lithium ion battery.

< laminated Unit of supercapacitor >

Illustratively, in one aspect of the present invention, the positive electrode tab C1, the separator and the compatible negative electrode tab F1 for the supercapacitor may form a supercapacitor lamination unit B1; the super capacitor lamination unit B1 comprises a super capacitor elementary structure Y2 formed by a positive electrode material for a super capacitor, a diaphragm and a negative electrode material for the super capacitor; meanwhile, when the materials of the positive plate for the supercapacitor and the compatible negative plate F1 are the same, the supercapacitor lamination unit contains a symmetrical supercapacitor elementary structure Y2-D; when the materials of the positive plate C and the compatible negative plate F1 are different supercapacitor active materials, the supercapacitor lamination unit contains an asymmetric supercapacitor elementary structure Y2-F. The compatibility negative electrode tab F1 may also be replaced by a negative electrode tab for a supercapacitor.

Illustratively, in one aspect of the present invention, the positive electrode tab for the supercapacitor, the separator, and the negative electrode tab F3 for the supercapacitor may form a supercapacitor laminated unit B2; the super capacitor lamination unit B2 comprises a super capacitor elementary structure Y2 formed by a positive electrode material for a super capacitor, a diaphragm and a negative electrode material for the super capacitor;

meanwhile, when the materials of the positive plate for the super capacitor and the negative plate F3 for the super capacitor are the same, the laminated unit of the super capacitor contains a symmetrical super capacitor element structure Y2-D; when the materials of the positive plate for the super capacitor and the negative plate F3 for the super capacitor are different super capacitor active materials, the super capacitor lamination unit contains an asymmetric super capacitor element structure Y2-F.

Those skilled in the art will appreciate that the above-described battery cells are merely exemplary and that those skilled in the art will know how to select the respective positive and negative electrode sheets to constitute a lithium ion battery lamination unit or a supercapacitor lamination unit in light of the present disclosure.

< transition Unit >

Illustratively, in one aspect of the present invention, the positive electrode sheet L1, the separator and the seventh negative electrode sheet F5 for a lithium ion battery may form a transition unit G1; the transition unit G1 comprises a lithium ion battery cell structure Y1 formed by a positive electrode material for a lithium ion battery, a diaphragm and a negative electrode material for the lithium ion battery.

Illustratively, in one aspect of the present invention, the positive electrode tab H, the separator and the compatibility negative electrode tab F1 for the lithium ion battery and the supercapacitor may form a transition unit G2; the transition unit G2 comprises a lithium ion battery cell structure Y1 formed by a positive electrode material for a lithium ion battery, a diaphragm and a negative electrode material for the lithium ion battery, or comprises a super capacitor cell structure Y2 formed by the positive electrode material for a super capacitor, the diaphragm and the negative electrode material for the super capacitor.

Illustratively, in one aspect of the present invention, the positive electrode tab H, the separator and the seventh negative electrode tab F5 for the lithium ion battery and the supercapacitor may form a transition unit G3; the transition unit G3 comprises a lithium ion battery cell structure Y1 formed by a positive electrode material for a lithium ion battery, a diaphragm and a negative electrode material for the lithium ion battery, or comprises a super capacitor cell structure Y2 formed by the positive electrode material for a super capacitor, the diaphragm and the negative electrode material for the super capacitor.

Illustratively, in one aspect of the present invention, the positive electrode tab C1, the separator and the seventh negative electrode tab F5 for the supercapacitor may form a transition unit G4; the transition unit G4 comprises a super capacitor elementary structure Y2 formed by a positive electrode material for a super capacitor, a diaphragm and a negative electrode material for the super capacitor.

Illustratively, in one aspect of the present invention, the positive electrode tab H for lithium ion batteries and supercapacitors, the separator, and the negative electrode tab F3 for supercapacitors may form a transition unit G5; the transition unit G5 comprises a super capacitor elementary structure Y2 formed by a positive electrode material for a super capacitor, a diaphragm and a negative electrode material for the super capacitor.

In the above scheme, the lithium ion battery anode material needs to correspond to a compatible cathode material; the super capacitor anode material needs to correspond to a super capacitor cathode material or a compatible cathode material.

In one scheme of the invention, a diaphragm is arranged among the lithium ion battery lamination unit, the supercapacitor lamination unit and the transition unit, so that the short circuit caused by direct contact of a positive electrode material and a negative electrode material is avoided.

For example, in an aspect of the present invention, the separator disposed between the lithium ion battery lamination unit, the supercapacitor lamination unit and the transition unit disposed adjacently may further form a lithium ion battery cell structure Y1 or a supercapacitor cell structure Y2, and specifically, when a positive electrode material for a lithium ion battery and a negative electrode material for a lithium ion battery are respectively disposed on both sides of the separator, a lithium ion battery cell structure Y1 may be formed; when the positive electrode material for the supercapacitor and the negative electrode material for the supercapacitor are respectively arranged on two sides of the separator, the supercapacitor elementary structure Y2 can be formed.

In an aspect of the present invention, in the composite battery according to the embodiment of the present invention, the number of the lithium ion battery cell structures Y1 is equal to or greater than the number of the supercapacitor cell structures Y2.

< Stacking of Positive and negative electrodes in composite type Battery >

In one aspect of the present invention, the hybrid battery includes at least one of a lithium ion battery lamination unit a1, an ultracapacitor lamination unit B1, an ultracapacitor lamination unit B2, and transition units G1, G2, G3, G4, G5; and simultaneously ensuring that the composite battery comprises at least one positive plate for the lithium ion battery and at least one positive plate for the super capacitor; and/or at least one positive plate H for the lithium ion battery and the super capacitor.

In one aspect of the present invention, the lithium ion battery lamination unit a1, the supercapacitor lamination unit B1, and the supercapacitor lamination unit B2 may be transitionally connected by a separator and optionally a transition unit to form a laminated composite battery.

In the scheme, the transitional connection is required to meet the condition that the lithium ion battery anode material corresponds to the compatible cathode material; the super capacitor anode material corresponds to a super capacitor cathode material or a compatible cathode material.

In an exemplary aspect, the composite battery comprises a transition unit m lithium ion battery lamination units a1-a transition unit; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, and m is an integer of 1 or more;

in an exemplary aspect, the hybrid battery comprises a transition cell-n supercapacitor lamination cells B1-a transition cell; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, and n is an integer of 1 or more;

in an exemplary aspect, the hybrid battery comprises a transition cell-n supercapacitor lamination cells B2-a transition cell; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, and n is an integer of 1 or more;

illustratively, the hybrid battery includes a transition cell-n 1 ultracapacitor laminate cells B1-n2 ultracapacitor laminate cells B2-transition cells; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, n1 is an integer of 1 or more, and n2 is an integer of 1 or more;

in an exemplary aspect, the composite battery comprises a transition cell-m lithium ion battery lamination cells a1-a transition cell-n supercapacitor lamination cells B1-a transition cell; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, n is an integer of 1 or more, and m is an integer of 1 or more;

in an exemplary aspect, the composite battery comprises a transition cell-m lithium ion battery lamination cells a1-a transition cell-n supercapacitor lamination cells B2-a transition cell; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, n is an integer of 1 or more, and m is an integer of 1 or more;

in an exemplary aspect, the hybrid battery comprises transition units-n 1 supercapacitor lamination units B1-transition units-m lithium ion battery lamination units a 1-transition units-n 2 supercapacitor lamination units B2-transition units; wherein the transition units are the same or different and are independently selected from the transition units G1-G5, n1+ n2 is an integer of 1 or more, and m is an integer of 1 or more;

in the above exemplary scheme, the transition unit may select a suitable transition unit from the transition units G1-G5 according to the difference between adjacent repeating units, so as to ensure that the lithium ion battery positive electrode material needs to correspond to a compatible negative electrode material; the super capacitor anode material needs to correspond to a super capacitor cathode material or a compatible cathode material.

In the above exemplary embodiment, if x lithium ion battery cell structures Y1 and Y supercapacitor cell structures Y2 are included, the application range and application of the composite battery can be adjusted by adjusting the ratio of x to Y, for example, when the ratio of x to Y is larger, the energy density of the composite battery is larger; the closer the ratio of x/y approaches 1, the greater the power density of the hybrid battery. The ratio of x to y can be adjusted according to the requirements of energy density and power density in a wide application environment to meet the application requirements, wherein x is more than or equal to y and is more than or equal to 1. Namely, the number of the supercapacitor cell structures Y2 is less than or equal to the number of the lithium ion battery cell structures Y1.

< separator >

In one aspect of the invention, the separator is selected from porous films.

The diaphragm is used for preparing an ion-conducting and electronic-insulating diaphragm material, and most of the diaphragms are porous films made of polymers.

In some embodiments, the polymers include, but are not limited to: polyethylene terephthalate, polybutylene terephthalate, polyether, polyacetal, polyamide, polycarbonate, polyimide, polyether ether ketone, polyether sulfone, polyphenylene ether, polyphenylene sulfide, polyethylene naphthalene, high density polyethylene, low density polyethylene, linear low density polyethylene, ultra high molecular weight polyethylene, and polypropylene.

In some embodiments, the separator further comprises an organic or inorganic coating disposed on one or both surfaces of the porous membrane. The organic or inorganic coating applied to the surface of the substrate is generally to enhance the electrical resistivity of the separator, prevent direct electrical contact between the opposing layers of negative electrode material and the layers of positive electrode material, and maintain an insulator material for impregnation with electrolyte and for transferring the lithium ion porous structure between the battery electrodes. The insulating separator may be in the form of a sheet adapted to the structure of the battery or in the form of a bag adapted to the structure of the battery.

In some embodiments, the inorganic substances may specifically include, but are not limited to: BaTiO 2₃、Pb(Zr，Ti)O₃(PZT)、Pb_1-xLa_xZr_1-yTi_yO₃、PB(Mg₃Nb_2/3)O₃-PbTiO₃Hafnium oxide (HfO)₂)、SrTiO₃、SnO₂、CeO₂、MgO、NiO、CaO、ZnO、ZrO₂、SiO₂、Y₂O₃、Al₂O₃、SiC、TiO₂And mixtures thereof.

In some embodiments, the organic material may specifically include, but is not limited to: cyanoethylpullulan, cyanoethylpolyvinyl alcohol, cyanoethylcellulose, cyanoethylsucrose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyimide, polyethylene oxide, cellulose acetate butyrate and cellulose acetate propionate, and mixtures thereof.

< composite type Battery >

In one aspect of the present invention, the composite battery includes a positive electrode sheet for a lithium ion battery, a positive electrode sheet for a supercapacitor, a positive electrode sheet for a lithium ion battery and a supercapacitor, and a negative electrode sheet. And assembling the positive plate and the negative plate, the tabs, the diaphragms, the electrolyte and the packaging shell into a finished product battery core.

< electrolyte solution >

In one aspect of the present invention, the electrolyte includes a lithium salt, an organic solvent, and an additive.

In some embodiments, the organic solvent is selected from at least one of a carbonate (e.g., cyclic carbonate, chain carbonate), a carboxylate (e.g., cyclic carboxylate, chain carboxylate), an ether compound (e.g., cyclic ether compound, chain ether compound), a phosphorus-containing compound, and a sulfur-containing compound.

Wherein the carbonate is at least one selected from the group consisting of dimethyl carbonate, methylethyl carbonate, diethyl carbonate, methyl-n-propyl carbonate, ethyl-n-propyl carbonate, di-n-propyl carbonate, bis (fluoromethyl) carbonate, bis (difluoromethyl) carbonate, bis (trifluoromethyl) carbonate, bis (2-fluoroethyl) carbonate, bis (2, 2-difluoroethyl) carbonate, bis (2,2, 2-trifluoroethyl) carbonate, 2-fluoroethyl methyl carbonate, 2, 2-difluoroethyl methyl carbonate and 2,2, 2-trifluoroethyl methyl carbonate.

Wherein the carboxylic ester is at least one selected from methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, sec-butyl acetate, isobutyl acetate, tert-butyl acetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, methyl isobutyrate, ethyl isobutyrate, methyl valerate, ethyl valerate, methyl pivalate and ethyl pivalate, methyl trifluoroacetate, ethyl trifluoroacetate, propyl trifluoroacetate, butyl trifluoroacetate, trifluoroacetic acid and 2,2, 2-trifluoroethyl ester.

Wherein the ether compound is at least one selected from tetrahydrofuran, 2-methyltetrahydrofuran, 1, 3-dioxolane, 2-methyl-1, 3-dioxolane, 4-methyl-1, 3-dioxolane, 1, 3-dioxane, 1, 4-dioxane, dimethoxypropane, dimethoxymethane, 1-dimethoxyethane, 1, 2-dimethoxyethane, diethoxymethane, 1-diethoxyethane, 1, 2-diethoxyethane, ethoxymethoxymethane, 1-ethoxymethoxyethane and 1, 2-ethoxymethoxyethane.

Wherein the phosphorus-containing compound is selected from at least one of trimethyl phosphate, triethyl phosphate, dimethyl ethyl phosphate, methyl diethyl phosphate, ethylene methyl phosphate, ethylene ethyl phosphate, triphenyl phosphate, trimethyl phosphite, triethyl phosphite, triphenyl phosphite, tris (2,2, 2-trifluoroethyl) phosphate, and tris (2,2,3,3, 3-pentafluoropropyl) phosphate.

Wherein the sulfur-containing compound is at least one selected from sulfolane, 2-methylsulfolane, 3-methylsulfolane, dimethylsulfone, diethylsulfone, ethylmethylsulfone, methylpropylsulfone, dimethylsulfoxide, methyl methanesulfonate, ethyl methanesulfonate, methyl ethanesulfonate, ethyl ethanesulfonate, dimethyl sulfate, diethyl sulfate and dibutyl sulfate.

In some embodiments, the organic solvent comprises 82-88% of the total mass of the electrolyte.

In one embodiment of the present invention, the lithium salt is at least one selected from an inorganic lithium salt, a fluorine-containing organic lithium salt, and a dicarboxylic acid complex-containing lithium salt.

Wherein the inorganic lithium salt is selected from LiClO₄、LiAsF₆、LiPF₆、LiBF₄、LiSbF₆、LiSO₃F、LiN(FSO₂)₂At least one of (1).

Wherein the fluorine-containing organic lithium salt is selected from LiCF₃SO₃、LiN(FSO₂)(CF₃SO₂)、LiN(CF₃SO₂)₂、LiN(C₂F₅SO₂)₂Cyclic 1, 3-hexafluoropropane disulfonimide lithium, cyclic 1, 2-tetrafluoroethane disulfonimide lithium, LiN (CF)₃SO₂)(C₄F₉SO₂)、LiC(CF₃SO₂)₃、LiPF₄(CF₃)₂、LiPF₄(C₂F₅)₂、LiPF₄(CF₃SO₂)₂、LiPF₄(C₂F₅SO₂)₂、LiBF₂(CF₃)₂、LiBF₂(C₂F₅)₂、LiBF₂(CF₃SO₂)₂、LiBF₂(C₂F₅SO₂)₂And the like.

Wherein the dicarboxylic acid complex-containing lithium salt is at least one selected from the group consisting of lithium bis (oxalate) borate, lithium difluorooxalate borate, lithium tris (oxalate) phosphate, lithium difluorobis (oxalate) phosphate and lithium tetrafluoro (oxalate) phosphate.

In some embodiments, the lithium salt comprises 13 to 18 wt% of the total mass of the electrolyte.

In one embodiment of the present invention, the additive is a conventional additive known in the art.

< method for producing composite Battery >

Illustratively, the invention also provides a preparation method of the composite battery, which comprises the following steps:

(1) preparing a positive plate for a lithium ion battery and a positive plate for a super capacitor; and/or preparing positive plates for lithium ion batteries and super capacitors;

(2) preparing a negative plate;

(3) respectively leading out two independent positive pole lugs in a positive plate for the lithium ion battery and a positive plate for the super capacitor, or respectively leading out two independent positive pole lugs in the positive plates for the lithium ion battery and the super capacitor; a negative pole tab is led out of the negative pole piece to form a three-pole tab type structure with two mutually independent positive pole tabs and a shared negative pole tab;

(4) and alternately stacking the negative plate, the diaphragm, the positive plate, the diaphragm and the negative plate according to a mode to form the composite battery.

In one embodiment of the invention, the positive plate for the supercapacitor can be prepared by the following method:

preparing positive electrode slurry for the super capacitor, and coating the positive electrode slurry on the surface of one side or two sides of a positive current collector for the super capacitor to prepare the positive electrode plate for the super capacitor.

In one aspect of the present invention, the positive electrode sheet for a lithium ion battery may be prepared by the following method:

preparing positive electrode slurry for the lithium ion battery, and coating the positive electrode slurry on the surface of one side or two sides of a positive electrode current collector for the lithium ion battery to prepare the positive plate for the lithium ion battery.

In one aspect of the present invention, the positive electrode sheet for lithium ion batteries and supercapacitors can be prepared by the following method:

preparing positive electrode slurry for a lithium ion battery and positive electrode slurry for a super capacitor, and respectively coating the positive electrode slurry and the positive electrode slurry on one side surface of a positive current collector for the lithium ion battery and the positive current collector for the super capacitor to prepare the positive electrode plate for the lithium ion battery and the positive electrode plate for the super capacitor.

In one aspect of the present invention, the negative electrode sheet, the separator G, the positive electrode sheet, the separator G, and the negative electrode sheet are alternately stacked in a pattern to form a composite type battery, as shown in fig. 7, 8, and 9, for example.

FIG. 7 is a schematic diagram of a composite capacitor including a symmetrical supercapacitor according to an embodiment of the present invention, which is laminated in the form of F2-single, diaphragm, (L-double, diaphragm, F1-double,Diaphragm), (L-double, diaphragm, F5, diaphragm), (C-double, diaphragm, F3-double, diaphragm), (C-double, diaphragm, F5, diaphragm), m (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single mode alternate combination, the diaphragm adopts Z type lamination, the positive and negative poles are separately overlapped to form naked electric core, form and contain A1-G1-B2-G4- (A1)_mWherein the F2-single, diaphragm, and L-double comprise a lithium ion battery cell structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and G1; the transition unit G1 comprises a lithium ion battery cell structure Y1; a supercapacitor cell structure Y2 is formed between G1-B2; the supercapacitor lamination unit B2 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B2 and G4; the transition unit G4 comprises a super capacitor cell structure Y2; a lithium ion battery elementary structure Y1 is formed between G4-A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and A1; the L-double, the diaphragm and the F2-single cell comprise a lithium ion battery elementary structure Y1.

FIG. 8 is a schematic structural diagram of a composite capacitor including an asymmetric supercapacitor according to an embodiment of the present invention, in which the lamination mode is F2-single, diaphragm, (L-double, diaphragm, F1-double, diaphragm), (C-double, diaphragm, F1-double, diaphragm), m (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single, and the diaphragms are alternately combined in a Z-type lamination mode, and positive and negative electrodes are separately stacked to form a bare cell, so as to form a composite capacitor including A1-B1- (A1)_mThe stacking structure of (1); wherein, the F2-single, the diaphragm and the L-double comprise a lithium ion battery elementary structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a supercapacitor cell structure Y2 is formed between A1 and B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a lithium ion battery elementary structure Y1 is formed between B1 and A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and A1; the L-double, the diaphragm and the F2-single cell comprise a lithium ion battery elementary structure Y1.

FIG. 9 is the present inventionIn an embodiment of the invention, the composite capacitor including the asymmetric supercapacitor and the symmetric supercapacitor has a lamination mode that F2-single, diaphragm, (L-double, diaphragm, F1-double, diaphragm), (L-double, diaphragm, F5, diaphragm), (C-double, diaphragm, F1-double, diaphragm), (C-double, diaphragm, F5, diaphragm), m (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single are combined alternately, the diaphragm adopts Z-type lamination, positive and negative electrodes are laminated to form a bare cell, and a structure containing A1-G1-B1-G4- (A1)_mWherein the F2-single, diaphragm, and L-double comprise a lithium ion battery cell structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and G1; the transition unit G1 comprises a lithium ion battery cell structure Y1; a supercapacitor cell structure Y2 is formed between G1-B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B1 and G4; the transition unit G4 comprises a super capacitor cell structure Y2; a lithium ion battery elementary structure Y1 is formed between G4-A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and A1; the L-double, the diaphragm and the F2-single cell comprise a lithium ion battery elementary structure Y1.

In one scheme of the invention, two independent positive pole tabs are respectively led out from a positive plate for a lithium ion battery and a positive plate for a super capacitor, or two independent positive pole tabs are respectively led out from the positive plates for the lithium ion battery and the super capacitor; a negative pole tab is led out of the negative pole piece to form a three-pole tab type structure with two mutually independent positive pole tabs and a shared negative pole tab; the problem of fast self-discharge of the super capacitor battery can be effectively solved, and the purpose of optimally using the hybrid electrochemical battery is achieved.

In one aspect of the invention, a first positive electrode tab is led out of a positive electrode sheet for a super capacitor; leading out a second positive electrode tab in the positive plate for the lithium ion battery; when a plurality of positive plates for the lithium ion batteries and the super capacitors are used, some positive plates can be led out of the first positive electrode tabs, and other positive plates can be led out of the second positive electrode tabs.

In one scheme of the invention, independent or cross-connected negative pole tabs are led out from the negative pole pieces.

The positions where the three tabs are arranged are not particularly limited, as shown in fig. 10, for example, a first positive tab connecting the positive plate of the super capacitor and a second positive tab connecting the positive plate of the lithium ion battery are arranged on the same side of the battery (as shown by a in fig. 10), or the first positive tab and the second positive tab are arranged on opposite sides of the battery (as shown by b in fig. 10), or the first positive tab and the second positive tab are arranged on adjacent sides of the battery (as shown by c and d in fig. 10). Two anodal utmost point ears set up when the adjacent both sides of battery, can suitably increase anodal utmost point ear's width according to the service environment of difference, and anodal utmost point ear can regard as good heat-conduction medium, can improve battery radiating effect.

The preparation method of the present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.

The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.

Preparation example 1 Positive electrode sheet for supercapacitor

Porous carbon active carbon powder (specific surface area is more than or equal to 1000 m) as positive electrode active substance for super capacitor²And/g), a binder PVDF, conductive carbon black and carbon nanotubes are mixed and dispersed in NMP (N-methyl pyrrolidone), and the mixture is mixed and stirred in vacuum to obtain the anode slurry for the super capacitor, which is uniformly dispersed. Wherein the solid component comprises 93 wt% of positive electrode active material, 4 wt% of binder PVDF,2 wt% of conductive carbon black and 1 wt% of carbon nanotubes. The total solid content in the positive electrode slurry for a supercapacitor was 40 wt%.

Uniformly coating the positive electrode slurry for the supercapacitor on two surfaces of an aluminum foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and rolling to compact the positive electrode slurry to 1.0-2.1g/cm³A positive electrode tab C1 for several supercapacitors was obtained and was denoted as C-bis (as shown in fig. 1 (C)).

Uniformly coating the positive electrode slurry for the supercapacitor on one surface of an aluminum foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and rolling to compact the positive electrode slurry to 0.9-2.1g/cm³Thus, several positive electrode sheets C2 for a supercapacitor were obtained and were denoted as C-sheet (see (b) in fig. 1).

Preparation example 2 Positive electrode sheet for lithium ion Battery

A positive electrode active material (LiNi) for a lithium ion battery_0.8Co_0.1Mn_0.1O₂) And the binder PVDF, the conductive carbon black and the carbon nano tubes are mixed and dispersed in NMP, and the mixture is mixed and then stirred in vacuum to obtain the anode slurry for the lithium ion battery, which is uniformly dispersed. Wherein the solid component comprises 94 wt% of the positive electrode active material, 3 wt% of the binder PVDF, 2 wt% of the conductive carbon black and 1 wt% of the carbon nanotube. The total solid content in the positive electrode slurry for a lithium ion battery was 70 wt%.

Uniformly coating the anode slurry for the lithium ion battery on two surfaces of an aluminum foil, vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, rolling to compact the anode slurry to 2-4.8g/cm³The lithium ion battery positive electrode sheet L1 was obtained and designated as L-bis (as shown in fig. 2 (c)).

Uniformly coating the anode slurry for the lithium ion battery on one surface of an aluminum foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and rolling to compact the anode slurry to 2-4.8g/cm³The lithium ion battery positive electrode sheet L2 was obtained and designated as L-sheet (see fig. 2 (b)).

Preparation example 3 Positive electrode sheet H for lithium ion batteries and supercapacitors

Respectively and uniformly coating the positive electrode slurry for the supercapacitor in preparation example 1 and the positive electrode slurry for the lithium ion battery in preparation example 2 on two sides of an aluminum foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and compacting to 0.9-3.8g/cm by using a roller press³To obtain a positive electrode sheet H for a lithium ion battery and a supercapacitor (as shown in fig. 3).

Preparation example 4 compatible negative electrode sheet

Mixing 95 wt% of artificial graphite, 2 wt% of binder SBR (polystyrene butadiene copolymer) and 3 wt% of conductive agent conductive carbon black in deionized water, and uniformly stirring and dispersing to prepare compatible negative electrode slurry, wherein the solid content in the compatible negative electrode slurry is 45-55 wt%.

Uniformly coating the compatible cathode slurry on two sides of the copper foil, vacuum drying at 100-120 ℃ for 10-24h, and compacting to 0.9-2.1g/cm by a roller press³Several compatibility negative electrode sheets F1 were obtained and were designated as F1-bis (as shown in fig. 4 (c)).

Uniformly coating the compatible cathode slurry on one surface of a copper foil, vacuum drying at 100-120 ℃ for 10-24h, and compacting to 0.9-2.1g/cm by a roller press³And a plurality of compatible negative electrode sheets F2 (shown as (b) in fig. 4) are obtained and are marked as F2-sheet.

Preparation example 5 seventh negative electrode sheet

Porous carbon active carbon powder (specific surface area is more than or equal to 1000 m) as negative active material for super capacitor²And/g), a binder PVDF, conductive carbon black and carbon nanotubes are mixed and dispersed in NMP (N-methyl pyrrolidone), and the mixture is mixed and stirred in vacuum to obtain the cathode slurry for the super capacitor, which is uniformly dispersed. Wherein the solid component contained 93 wt% of the negative electrode active material, 4 wt% of the binder PVDF, 2 wt% of the conductive carbon black, and 1 wt% of the carbon nanotube. The total solid content in the anode slurry for a supercapacitor was 40 wt%.

Respectively and uniformly coating the negative electrode slurry for the supercapacitor and the compatible negative electrode slurry prepared in the preparation example 4 on two sides of a copper foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and compacting to 0.9-2.1g/cm by using a roller press³And a plurality of seventh negative electrode tabs F5 (shown in fig. 5) are obtained.

Preparation example 6 negative electrode sheet for supercapacitor

Uniformly coating the cathode slurry for the supercapacitor in preparation example 5 on two surfaces of a copper foil, performing vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and compacting to 0.9-2.1g/cm by a roller press³Obtaining a plurality of negative electrode sheets F3 for the super capacitor and marking as F3Double (as shown in fig. 6 (c)).

Uniformly coating the cathode slurry for the supercapacitor of the preparation example 5 on one surface of a copper foil, carrying out vacuum drying at the temperature of 100 ℃ and 120 ℃ for 10-24h, and compacting to 0.9-2.1g/cm by a roller press³Several negative electrode sheets F4 for supercapacitors were obtained and were denoted as F4-sheet (as shown in fig. 6 (b)).

Example 1 combination of a symmetrical supercapacitor containing a lithium ion battery

The positive electrode sheets of the above preparation examples 1 to 3 were punched out into sheets of 60mm × 45 mm; the negative electrode sheets of the above preparation examples 4 to 6 were die-cut into sheets of 62mm × 47 mm;

the anode and cathode pole pieces are as follows: f2-single, diaphragm, (L-double, diaphragm, F1-double, diaphragm), (L-double, diaphragm, F5, diaphragm), 2 (C-double, diaphragm, F3-double, diaphragm), (C-double, diaphragm, F5, diaphragm), (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single mode alternate combination, wherein, one surface of the transitional negative electrode F5 is provided with a super capacitor negative electrode material, and the other surface is provided with a lithium ion battery negative electrode material, thereby forming the composite material containing A1-G1- (B2)₂-G4-a1, the active material of the supercapacitor positive electrode material being the same as the active material of the supercapacitor negative electrode material. Wherein, the F2-single, the diaphragm and the L-double comprise a lithium ion battery elementary structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and G1; the transition unit G1 comprises a lithium ion battery cell structure Y1; a supercapacitor cell structure Y2 is formed between G1-B2; the supercapacitor lamination unit B2 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B2 and B2; the supercapacitor lamination unit B2 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B2 and G4; the transition unit G4 comprises a super capacitor cell structure Y2; a lithium ion battery elementary structure Y1 is formed between G4-A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; f1-double, diaphragm, L-double including lithium ion battery elementary structure Y1; the L-double, the diaphragm and the F2-single cell comprise a lithium ion battery elementary structure Y1.

The diaphragm prepared by polypropylene (PP) or Polyethylene (PE) adopts Z-shaped lamination, and the positive electrode and the negative electrode are separately laminated to form a naked electric core C-1. And respectively transferring the positive plate L for the lithium ion battery and the positive plate C for the super capacitor in the bare cell C-1 out of two independent aluminum pole lugs and transferring the negative plate out of a copper nickel plating pole lug or a nickel pole lug to form a three-pole-lug bare cell C-1 with two independent positive pole lugs and a shared negative pole lug.

Then, the naked electric core is clamped tightly by a glass clamp, and the strength of the glass clamp is 100MPa/m²Vacuum baking at 85 deg.C for 24 hr, packaging with aluminum-plastic film, adding electrolyte, packaging, and aging to obtain the final product with length, width and thickness of 70mm × 50mm × 7 mm. The electrolyte adopts 1M lithium hexafluorophosphate electrolyte, and the solvent of the electrolyte is ethylene carbonate with the volume ratio of 1:1: 1: dimethyl carbonate: 1,2 propylene glycol carbonate.

Example 2 combination of lithium ion battery and asymmetric supercapacitor

The other operations are the same as example 1, except that:

the anode and cathode pole pieces are as follows: is formed by the mode alternate combination of F2-single, diaphragm, 2 (L-double, diaphragm, F1-double, diaphragm), 3 (C-double, diaphragm, F1-double, diaphragm), 1 (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm and F2-single, and comprises (A1)₂-(B1)₃-(A1)₁In a stacked configuration. Wherein, the F2-single, the diaphragm and the L-double comprise a lithium ion battery elementary structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a supercapacitor cell structure Y2 is formed between A1 and B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B1 and B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B1 and B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; B1-A1Forming a super capacitor cell structure Y2; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; f1-double, diaphragm, L-double including lithium ion battery elementary structure Y1; the L-double, the diaphragm and the F2-single cell comprise a lithium ion battery elementary structure Y1.

The diaphragm prepared by polypropylene (PP) or Polyethylene (PE) adopts Z-shaped lamination, and the positive electrode and the negative electrode are separately laminated to form a naked electric core C-2. And respectively transferring the positive plate L for the lithium ion battery and the positive plate C for the super capacitor in the bare cell C-2 out of two independent aluminum pole lugs and transferring the negative plate out of a copper nickel plating pole lug or a nickel pole lug to form a three-pole-lug bare cell C-2 with two independent positive pole lugs and a shared negative pole lug.

Example 3 combination of lithium ion batteries, symmetrical supercapacitors and asymmetrical supercapacitors

The other operations are the same as example 1, except that:

the anode and cathode pole pieces are as follows: f2-single, diaphragm, (L-double, diaphragm, F1-double, diaphragm), (L-double, diaphragm, F5, diaphragm), 2 (C-double, diaphragm, F1-double, diaphragm), (C-double, diaphragm, F5, diaphragm), (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single mode alternate combination, form containing A1-G1- (B1)₂-a stacked structure of G4-a1, wherein F2-mono-, separator, L-bis comprises a lithium ion battery cell structure Y1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; a lithium ion battery elementary structure Y1 is formed between A1 and G1; the transition unit G1 comprises a lithium ion battery cell structure Y1; a supercapacitor cell structure Y2 is formed between G1-B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B1 and B1; the supercapacitor lamination unit B1 comprises a supercapacitor cell structure Y2; a supercapacitor cell structure Y2 is formed between B1 and G4; the transition unit G4 comprises a super capacitor cell structure Y2; a lithium ion battery elementary structure Y1 is formed between G4-A1; the lithium ion battery lamination unit A1 comprises a lithium ion battery elementary structure Y1; f1-double, diaphragm, L-double including lithium ion battery elementary structure Y1; l-bisThe diaphragm and the F2-unit comprise a lithium ion battery elementary structure Y1.

The diaphragm prepared from polypropylene (PP) or Polyethylene (PE) adopts Z-shaped lamination, and the positive electrode and the negative electrode are separately laminated to form a naked electric core C-3. And respectively transferring the positive plate L for the lithium ion battery and the positive plate C for the super capacitor in the bare cell C-3 out of two independent aluminum pole lugs and transferring the negative plate out of a copper nickel plating pole lug or a nickel pole lug to form a three-pole-lug bare cell C-3 with two independent positive pole lugs and a shared negative pole lug.

Comparative example 1 symmetrical supercapacitor

The other operations are the same as example 1, except that:

the anode and cathode pole pieces are as follows: f4-single, diaphragm, 7 (C-double, diaphragm, F3, diaphragm), C-double, diaphragm, F4-single, forming containing- (B2)₇-a stacked structure of 16 supercapacitor cell structures Y2.

A diaphragm prepared from polypropylene (PP) or Polyethylene (PE) adopts a Z-shaped lamination, and a positive electrode and a negative electrode are separately laminated to form a symmetrical supercapacitor-containing naked cell DBL-1. And then, transferring an aluminum tab from the positive plate C for the super capacitor in the bare cell DBL-1, and transferring a copper nickel-plated tab or a nickel tab from the negative plate to form a two-tab bare cell DBL-1.

Comparative example 2 asymmetric supercapacitor

The other operations are the same as example 1, except that:

the anode and cathode pole pieces are as follows: f2-single, diaphragm, 7 (C-double, diaphragm, F1-double, diaphragm), C-double, diaphragm, F2-single mode alternate combination, form contains- (B1)₇-a stacked structure of 16 supercapacitor cell structures Y2.

A diaphragm prepared from polypropylene (PP) or Polyethylene (PE) adopts a Z-shaped lamination, and a positive electrode and a negative electrode are separately laminated to form a symmetrical supercapacitor-containing naked cell DBL-2. And then, transferring an aluminum tab from the positive plate C for the super capacitor in the bare cell DBL-2, and transferring a copper nickel-plated tab or a nickel tab from the negative plate to form a two-tab bare cell DBL-2.

Comparative example 3 lithium ion battery

The other operations are the same as example 1, except that:

the anode and cathode pole pieces are as follows: f2-single, diaphragm, 7 (L-double, diaphragm, F1-double, diaphragm), L-double, diaphragm, F2-single mode alternate combination, form containing- (A1)₇-a stacked structure of 16 lithium ion battery cell structures Y1.

A diaphragm prepared from polypropylene (PP) or Polyethylene (PE) adopts a Z-shaped lamination, and a positive electrode and a negative electrode are separately laminated to form a symmetrical supercapacitor-containing naked cell DBL-3. And then, transferring the positive plate L for the lithium ion battery in the bare cell DBL-2 to form an aluminum tab, and transferring the negative plate to form a copper nickel-plated tab or a nickel tab to form a two-tab bare cell DBL-3.

Comparative example 4 lithium ion battery and asymmetric supercapacitor two-tab battery

The other operations are the same as those of example 2, except that:

the diaphragm prepared by polypropylene (PP) or Polyethylene (PE) adopts Z-shaped lamination, the positive electrode and the negative electrode are separately overlapped to form a naked cell DBL-4, all the positive electrode sheets L for the lithium ion battery and the aluminum electrode tabs rolled out by the positive electrode sheet C for the super capacitor are welded together to form a common leading-out end positive electrode tab, and the negative electrode sheet is rolled out to form a copper nickel plating tab or a nickel electrode tab to form a two-tab naked cell DBL-4.

Table 1 results of performance test of capacitors prepared in examples and comparative examples

As is apparent from table 1, the "capacity retention (%) at 4.2V at full electricity storage for 60 days" of the laminated composite batteries of examples 1 to 3 of the present invention is significantly superior to that of the two-tab laminated composite battery (comparative example 4). When the super capacitor is a symmetrical super capacitor (example 1), the power density is significantly higher than that when the super capacitor is an asymmetrical super capacitor (examples 2 and 3).

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-lug laminated composite battery is characterized by comprising a lithium ion battery laminated unit and a super capacitor laminated unit, wherein the lithium ion battery laminated unit comprises a positive plate, a negative plate and a diaphragm which can be used for a lithium ion battery, and the super capacitor laminated unit comprises a positive plate, a negative plate and a diaphragm which can be used for a super capacitor; the two outermost layers of the composite battery are selected from one of a positive plate with one side coated with a positive material and a negative plate with one side coated with a negative material; in each super capacitor lamination unit, the active material of the super capacitor positive electrode material is the same as that of the super capacitor negative electrode material;

the composite battery comprises a first positive electrode lug, a second positive electrode lug and a negative electrode lug which are mutually independent; the positive plate capable of being used for the super capacitor lamination unit is connected with a first positive electrode tab; the positive plate which can be used for the lithium ion battery lamination unit is connected with a second positive electrode lug, and the negative plates of the super capacitor lamination unit and the lithium ion battery lamination unit are connected with a negative electrode lug.

2. The composite type battery according to claim 1, wherein the positive electrode sheet that can be used for a supercapacitor is selected from the following positive electrode sheets:

3. The composite battery according to claim 1, wherein the negative electrode tab usable for a supercapacitor is selected from the following negative electrode tabs:

4. The composite battery according to claim 1, wherein the positive electrode sheet having one side coated with the positive electrode material is selected from the group consisting of:

5. The composite type battery according to claim 1, wherein the negative electrode sheet having one side coated with the negative electrode material is selected from the group consisting of the following negative electrode sheets;

6. The composite battery according to claim 1, wherein the positive electrode sheet that can be used in a lithium ion battery is selected from the group consisting of:

7. The composite battery according to claim 1, wherein the negative electrode sheet that can be used in a lithium ion battery is selected from the following negative electrode sheets:

8. The composite battery according to any one of claims 1 to 7, wherein when the composite battery comprises a third positive electrode tab, the third positive electrode tab is connected to the first positive electrode tab or the second positive electrode tab, the third positive electrode tab comprises a third positive electrode current collector, the lithium ion battery positive electrode material is disposed on a first surface of the third positive electrode current collector, and the supercapacitor positive electrode material is disposed on a second surface of the third positive electrode current collector opposite to the first surface.

9. The composite type battery according to claim 8, wherein the first and second positive electrode tabs are disposed at opposite sides of the composite type battery, or the first and second positive electrode tabs are disposed at adjacent sides of the battery.