CN110931867A

CN110931867A - Novel battery and preparation method thereof

Info

Publication number: CN110931867A
Application number: CN201911172263.XA
Authority: CN
Inventors: 唐永炳; 向立; 欧学武
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2019-11-26
Filing date: 2019-11-26
Publication date: 2020-03-27
Also published as: WO2021104059A1

Abstract

The invention provides a novel battery which comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, wherein the molar concentration of the electrolyte is 3 mol/L-saturated concentration. Compare with the traditional electrolyte that adopts molar concentration to be 1mol/L, this application novel battery adopt electrolyte concentration higher or even be close to the saturated condition novel battery that high concentration's electrolyte equipment obtained, at the in-process of charge-discharge, the SEI that high concentration electrolyte formed is favorable to alleviating the volume expansion of metal, can improve metal negative pole material's life to improve the specific capacity and the cycling stability of this novel battery, and the novel battery that enables to prepare simultaneously and obtain has the electrochemistry window of broad.

Description

Novel battery and preparation method thereof

Technical Field

The invention relates to the field of batteries, in particular to a novel battery and a preparation method thereof.

Background

The lithium ion battery has the advantages of high energy density, high coulombic efficiency, long cycle life, no memory effect, quick charge and discharge and the like, so that the lithium ion battery has great market demands in the fields of consumer electronics products, electric vehicles, power grid peak shaving, energy storage power supplies, aerospace and the like. The negative electrode material, which is a critical part of the battery, has a decisive influence on the performance of the battery. The battery negative electrode materials which are commercialized or have a commercial prospect currently include graphite negative electrodes, silicon negative electrodes, lithium metal negative electrodes, metal foils and the like. At present, a metal foil material, such as aluminum, tin, antimony and the like, is adopted as a battery cathode, a cathode active material and a cathode current collector are integrally designed, the battery is a novel and efficient battery system, the cathode current collector is omitted, the dead weight and the volume of the battery can be effectively reduced, the quality and the volume energy density of the battery are obviously improved, the production and manufacturing cost of the battery is greatly reduced, and the battery has wide universality.

However, the inexpensive metal foil as the negative electrode has the following problems: (1) in the charging and discharging process, the alloying/dealloying process of the metal foil negative electrode causes volume expansion and pulverization phenomena, thereby causing the attenuation of battery capacity and poor cycle performance; (2) because the volume of the metal negative electrode is continuously changed in the charging and discharging processes, and an SEI film formed on the surface of the metal negative electrode is unstable, the SEI film can be continuously generated, cracked and regenerated in the process of lithium, sodium, potassium and the like, a large amount of ions and electrolyte are consumed, and the coulombic efficiency of the battery is low; (3) burrs generated during the expansion and pulverization of the metal negative electrode may pierce the separator, resulting in a safety problem.

In view of the above problems, although a great deal of research has been carried out to improve the performance of the metal foil negative electrode in the early days, the current methods and means still have problems and certain limitations. In the prior art, an electrolyte additive is introduced to form a compact and stable SEI film on the surface of a negative electrode, so that the interface properties of the electrode and the electrolyte can be improved to a certain extent. However, the method has high requirements on the selection of additives, more factors need to be considered, and the effect is limited. The problem of expansion and pulverization of the aluminum foil cathode can be solved to a certain extent by adopting a carbon coating method. However, the carbon coating is an inorganic compound protective layer, which is also cracked to a certain extent in the volume expansion process of the aluminum negative electrode, so that the problems of volume expansion and capacity attenuation caused by an unstable solid electrolyte membrane cannot be effectively solved, and the process is complicated. Although the polymer coating can effectively isolate the electrolyte from the aluminum cathode and plays a certain role in inhibiting pulverization in the volume expansion process of the aluminum cathode, the operation process is more complex and the effect is limited. The adoption of the porous metal foil can play a role in relieving the volume expansion of the negative electrode in the charging and discharging processes to a certain extent, but the capacity attenuation problem caused by an unstable solid electrolyte membrane cannot be effectively improved, and the design process of the porous structure is complex.

Disclosure of Invention

The invention aims to provide a novel battery and a preparation method thereof, and aims to solve the problems of poor capacity and unstable cycle performance of the novel battery which adopts metal as a negative electrode.

In order to achieve the purpose, the invention adopts the following technical scheme:

a novel battery comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, wherein the molar concentration of the electrolyte is 3 mol/L-saturated concentration; the negative electrode is a metal negative electrode integrating a negative electrode current collector and a negative electrode material.

And, a method of making a novel battery, the method comprising the steps of:

preparing electrolyte with the molar concentration of 3 mol/L-saturated concentration;

and assembling the anode, the cathode, the diaphragm and the electrolyte to obtain the novel battery.

The novel battery comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, wherein the molar concentration of the electrolyte is 3 mol/L-saturated concentration; compare with the traditional electrolyte that adopts molar concentration to be 1mol/L, this application the higher or even close saturated state of electrolyte concentration that novel battery adopted, at the in-process of charge-discharge, the SEI that high concentration electrolyte formed is favorable to alleviating the volume expansion of metal, can improve metal negative pole material's life to improve the specific capacity and the cycling stability of this novel battery, and the novel battery that enables to prepare simultaneously and obtain has the electrochemistry window of broad.

The preparation method of the novel battery is simple and convenient, only high-concentration electrolyte needs to be prepared and then assembled with the anode, the cathode and the diaphragm, the preparation method is convenient to operate, simple in process and obvious in effect, and can be widely applied to battery systems based on metal cathodes, such as lithium, sodium, potassium and the like, and the application is wide.

Drawings

Fig. 1 is a schematic structural diagram of a novel battery provided in an embodiment of the present invention.

Fig. 2 is a charge-discharge curve diagram of the novel battery prepared in example 1 of the present invention.

Fig. 3 is a graph showing the charge and discharge performance of the novel battery prepared in example 1 of the present invention.

Fig. 4 is a charge-discharge curve diagram of the novel battery prepared in example 5 of the present invention.

Fig. 5 is a graph of the charge and discharge performance of the novel battery prepared in example 5 of the present invention.

Fig. 6 is a charge-discharge curve diagram of the novel battery prepared in example 9 of the present invention.

Fig. 7 is a graph showing the charge and discharge performance of the novel battery prepared in example 9 of the present invention.

Fig. 8 is a charge-discharge curve diagram of the novel battery prepared in example 13 of the present invention.

Fig. 9 is a graph showing the charge and discharge performance of the novel battery prepared in example 13 of the present invention.

Detailed Description

In order to make the objects, technical solutions and technical effects of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive step in connection with the embodiments of the present invention shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The embodiment of the invention provides a novel battery, as shown in fig. 1, the novel battery comprises a positive electrode 4, a negative electrode 1, a diaphragm 2 and an electrolyte 3, wherein the molar concentration of the electrolyte is 3 mol/L-saturated concentration; the negative electrode is a metal negative electrode integrating a negative electrode current collector and a negative electrode material.

Compared with the traditional electrolyte with the molar concentration of 1mol/L, the novel battery protected by the invention comprises a positive electrode, a negative electrode, a diaphragm and the electrolyte, wherein the molar concentration of the electrolyte is 3 mol/L-saturated concentration; compare with the traditional electrolyte that adopts molar concentration to be 1mol/L, this application novel battery adopt electrolyte concentration higher or even be close to the saturated condition, by the novel battery that high concentration's electrolyte equipment obtained, at the in-process of charging and discharging, the SEI that high concentration electrolyte formed is favorable to alleviating the volume expansion of metal, can improve metal negative pole material's life to improve the specific capacity and the cycling stability of this novel battery, and the novel battery that enables to prepare simultaneously and obtain has the electrochemistry window of broad.

In the embodiment of the invention, the negative electrode is selected from a metal negative electrode integrating a negative electrode current collector and a negative electrode material, and refers to a metal as the negative electrode, and simultaneously serves as the negative electrode current collector and the negative electrode material. Preferably, the material of the negative electrode is selected from any one of aluminum, magnesium, zinc, iron, cobalt, nickel, antimony, tin, bismuth, germanium and alloys thereof. . The novel battery system which adopts the metal foil as the negative electrode and integrally designs the negative electrode active material and the current collector can effectively reduce the dead weight and the volume of the battery, obviously improve the quality and the volume energy density of the battery and greatly reduce the production and manufacturing cost of the battery. In an embodiment of the present invention, the electrolyte includes an electrolyte salt and a solvent. Further, the electrolyte salt is selected from any one of lithium salt, sodium salt, potassium salt and calcium salt, and different electrolyte types can be selected according to the types and performances of different batteries.

Further preferably, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroarsenate, lithium perchlorate, lithium nitrate, lithium trifluoromethanesulfonate, lithium bis (trifluoromethanesulfonate) imide, lithium bis (fluorosulfonyl) imide and its derivatives, lithium perfluoroalkyl phosphate, lithium tetrafluorooxalate phosphate, lithium bis (oxalato) borate, lithium tris (catechol) phosphate and sulfonated polysulfonamide lithium salts. In a preferred embodiment of the present invention, when the material of the negative electrode is lithium metal, the electrolyte is lithium bis (fluorosulfonyl) imide (LiFSI).

Further preferably, the sodium salt is selected from at least one of sodium hexafluorophosphate, sodium fluoroborate, sodium hexafluoroarsenate, sodium high aluminate, sodium nitrate, sodium trifluoromethanesulfonate, sodium bis (trifluoromethanesulfonate) imide, sodium bis (fluorosulfonyl) imide and derivatives thereof, sodium bis (oxalato), sodium perfluoroalkyl phosphate, sodium tetrafluorooxalato, sodium tris (catechol) phosphate, and sodium sulfonated polysulfonamide. In the preferred embodiment of the present invention, when the cathode material is tin metal, the electrolyte may be sodium bis (fluorosulfonyl) imide (NaFSI).

Further preferably, the potassium salt is selected from at least one of potassium hexafluorophosphate, potassium fluoroborate, potassium hexafluoroarsenate, potassium aluminate, potassium nitrate, potassium sulfate, potassium chloride, potassium trifluoromethanesulfonate, potassium bis (trifluoromethanesulfonate) imide, potassium bis (fluorosulfonyl) imide and derivatives thereof, potassium dodecylbenzenesulfonate, potassium dodecylsulfate, potassium perfluoroalkyl phosphate, potassium tetrafluorooxalate, potassium tris (catechol) phosphate, sulfonated potassium polysulfonamide, potassium bis-oxalate, potassium difluorooxalate, potassium pyrophosphate, and potassium citrate. In the preferred embodiment of the present invention, when antimony metal is used as the negative electrode material, potassium bis (fluorosulfonyl) imide (KFSI) may be used as the electrolyte.

Further preferably, the calcium salt is selected from at least one of calcium hexafluorophosphate, calcium borate, calcium metaborate, calcium hexafluoroarsenate, calcium perchlorate, calcium tetrafluoroborate, calcium phosphate, calcium nitrate, calcium difluorooxalato borate, calcium pyrophosphate, calcium dodecylbenzenesulfonate, calcium dodecylsulfate, calcium molybdate, calcium tungstate, calcium bromide, calcium oxalate, calcium aluminate, calcium acetate, calcium lignosulfonate, calcium methanesulfonate, calcium trifluoromethanesulfonimide, and calcium trifluoromethanesulfonate.

Preferably, the solvent is selected from any one of an ester organic solvent, a sulfone organic solvent, an ether organic solvent and a nitrile organic solvent. Different kinds of solvents are selected to be dissolved with the above electrolyte salt to prepare an electrolytic solution, as long as the solvents can dissociate the electrolyte salt into metal cations and anions, and the cations and anions can freely migrate. Further preferably, the solvent is selected from at least one of ethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, propylene carbonate, diethyl carbonate, methyl formate, methyl acetate, N-dimethylacetamide, fluoroethylene carbonate, methyl propionate, ethyl acetate, γ -butyrolactone, tetrahydrofuran, 2-methyltetrahydrofuran, 1, 2-dimethoxypropane 1, 3-dioxolane, 4-methyl-1, 3-dioxolane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dimethyl sulfone, sulfolane, dimethyl ether, dimethoxymethane, ethylene sulfite, propylene sulfite, and diethyl sulfite. In a preferred embodiment of the present invention, the solvent is a mixture of ethylene carbonate and dimethyl carbonate, wherein the addition mass of ethylene carbonate and dimethyl carbonate is 1: 1.

in an embodiment of the present invention, the positive electrode includes a positive electrode current collector and a positive electrode material bonded to the positive electrode current collector.

Preferably, the positive electrode material is selected from any one of lithium cobaltate, lithium iron phosphate, nickel-cobalt-manganese ternary materials, crystalline flake graphite, mesocarbon microbeads, molybdenum disulfide, activated carbon, porous graphene and array carbon nanotubes. In a preferred embodiment of the invention, the positive electrode material is selected from expanded graphite or nickel cobalt manganese ternary material.

Preferably, the positive electrode current collector is selected from any one of aluminum foil, tin foil, magnesium foil, zinc foil, copper foil, iron foil, nickel foil, titanium foil, manganese foil, antimony foil and bismuth foil. More preferably, the positive electrode current collector is selected from alloy materials containing any one metal element of aluminum, tin, magnesium, zinc, copper, iron, nickel, titanium, manganese, antimony, and bismuth. Preferably, the performance of the prepared novel battery is influenced by the fact that the thickness of the positive electrode current collector is 10-1000 mu m, and the thickness of the positive electrode current collector is too thin or too thick.

Preferably, the separator is selected from any one of a plurality of glass fibers, a porous polyethylene film, a porous polypropylene film, a porous composite polymer film, a non-woven fabric and a porous ceramic separator.

Preferably, the current density of charge and discharge of the novel battery is 0.01mA/cm²～5mA/cm². Novel battery electrolyte concentration is big, and when electrolyte concentration is great, mobilizable ion concentration is great in the electrolyte, so this novel battery can use less current density can accomplish the charge-discharge, and the battery of less current density can not produce too much heat at the formation in-process, improves its life.

The novel battery provided by the embodiment of the invention can be prepared by the following method.

Correspondingly, the embodiment of the invention also provides a preparation method of the novel battery, which comprises the following steps:

s01, preparing electrolyte with the molar concentration of 3 mol/L-saturated concentration;

and S02, assembling the anode, the cathode, the diaphragm and the electrolyte to obtain the novel battery.

Specifically, in step S01, the electrolyte solution having a molar concentration of 3mol/L to a saturation concentration is disposed. The selection of the specific electrolyte and solvent is described above and will not be described herein for brevity.

Specifically, in step S02, a positive electrode is prepared first, and the positive electrode is prepared by the following method: grinding the positive active substance, the adhesive and the conductive carbon black into slurry according to a certain proportion, coating the slurry on a metal foil current collector and drying the current collector, and cutting the dried pole piece to obtain the positive pole with the required size.

Preparing a negative electrode, selecting a proper negative electrode material, cutting the negative electrode material, and drying for later use.

Preparing a diaphragm, selecting a proper diaphragm material, cutting the diaphragm material, and drying for later use.

The preparation method of the novel battery is simple and convenient, only high-concentration electrolyte needs to be prepared, and then the novel battery is assembled with the anode, the cathode and the diaphragm, and the preparation method is convenient to operate, simple in process and obvious in effect.

The following specific examples are further illustrative.

Example 1

A battery is assembled by taking LiFSI/EC: DMC (1:1) as an electrolyte, graphite as a positive electrode, a metal lithium foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

(1) preparing a positive electrode: adding 0.8g of expanded graphite, 0.1g of conductive carbon black and 0.1g of polyvinylidene fluoride into 2mL of N-methylpyrrolidone, and fully grinding to obtain uniform slurry; and then coating the slurry on the surface of an aluminum foil, carrying out vacuum drying at 80 ℃ for 12 hours, cutting into a circular sheet with the diameter of 10mm, and placing the circular sheet in a glove box to serve as a battery anode for standby.

(2) Preparing a negative electrode: cutting a metal foil with the diameter of 12mm, and drying to be used as a negative electrode for later use.

(3) Electrolyte solution: and taking 1ml of EC and 1ml of DMC as solvents, continuously adding the electrolyte LiFSI into the solvents, stirring to fully dissolve the electrolyte to prepare the electrolyte with saturated concentration, and then adding a lithium type molecular sieve to remove water.

(4) Preparing a diaphragm: cutting the glass fiber paper into round pieces with the diameter of 19mm, drying in vacuum at 80 ℃ for 12h, and placing in a glove box to be used as a diaphragm for standby.

(5) Assembling the battery: and (3) in a glove box in an argon atmosphere, tightly stacking the prepared positive electrode, the diaphragm and the negative electrode in sequence, dripping electrolyte to completely soak the diaphragm, and packaging the stacked part into a shell to prepare the novel battery.

Example 2

Compared with the embodiment 1, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 5mol/L prepared'; other steps were the same as in example 1, and a battery was manufactured.

Example 3

Compared with the embodiment 1, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 3.5mol/L prepared'; other steps were the same as in example 1, and a battery was manufactured.

Example 4

Compared with the embodiment 1, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 1mol/L prepared'; other steps were the same as in example 1, and a battery was manufactured.

Example 5

A battery is assembled by taking LiFSI/EC: DMC (1:1) as an electrolyte, graphite as a positive electrode, a metal aluminum foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 6

Compared with the embodiment 5, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 5mol/L prepared'; other steps were the same as in example 5, and a battery was manufactured.

Example 7

Compared with the embodiment 5, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 3.5mol/L prepared'; other steps were the same as in example 5, and a battery was manufactured.

Example 8

Compared with the embodiment 5, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 1mol/L prepared'; other steps were the same as in example 5, and a battery was manufactured.

Example 9

A battery is assembled by taking LiFSI/EC: DMC (1:1) as an electrolyte, a ternary material as a positive electrode, a metal lithium foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 10

Compared with the example 9, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 5mol/L prepared'; other steps were the same as in example 9, and a battery was manufactured.

Example 11

Compared with the example 9, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 3.5mol/L prepared'; other steps were the same as in example 9, and a battery was manufactured.

Example 12

Compared with the example 9, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 1mol/L prepared'; other steps were the same as in example 9, and a battery was manufactured.

Example 13

A battery is assembled by taking LiFSI/EC: DMC (1:1) as an electrolyte, a ternary material as a positive electrode, a metal aluminum foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 14

Compared with the example 13, the 'electrolyte prepared to obtain the saturated concentration' is replaced by the 'electrolyte prepared to obtain the concentration of 5 mol/L'; other steps were the same as in example 13, and a battery was manufactured.

Example 15

Compared with the example 13, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 3.5mol/L prepared'; other steps were the same as in example 13, and a battery was manufactured.

Example 16

Compared with the example 13, the 'electrolyte prepared to obtain the saturated concentration' is replaced by the 'electrolyte prepared to obtain the concentration of 1 mol/L'; other steps were the same as in example 13, and a battery was manufactured.

Example 17

The battery is assembled by taking NaFSI/EC: DMC (1:1) as electrolyte, expanded graphite as a positive electrode, metal tin foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

(3) Electrolyte solution: and taking 1ml of EC and 1ml of DMC as solvents, continuously adding the electrolyte NaFSI into the solvents, stirring to fully dissolve the electrolyte to prepare the electrolyte with saturated concentration, and then adding a lithium type molecular sieve to remove water.

Example 18

Compared with the example 17, the 'electrolyte solution with the saturation concentration prepared' is replaced by the 'electrolyte solution with the concentration of 1mol/L prepared'; other steps were the same as in example 17, and a battery was produced.

Example 19

The battery is assembled by taking NaFSI/EC: DMC (1:1) as electrolyte, expanded graphite as a positive electrode, metal antimony foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 20

Compared with the example 19, the 'electrolyte prepared to obtain the saturated concentration' is replaced by the 'electrolyte prepared to obtain the concentration of 1 mol/L'; other steps were the same as in example 19, and a battery was produced.

Example 21

A battery is assembled by taking KFSI/EC: DMC (1:1) as electrolyte, expanded graphite as a positive electrode, metal tin foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 22

Compared with the embodiment 21, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 1mol/L prepared'; other steps were the same as in example 21, and a battery was produced.

Example 23

A battery is assembled by taking KFSI/EC: DMC (1:1) as electrolyte, expanded graphite as a positive electrode, metal antimony foil as a negative electrode and glass fiber as a diaphragm, and the process is as follows:

Example 24

Compared with the embodiment 23, the 'electrolyte with the saturation concentration prepared' is replaced by 'the electrolyte with the concentration of 1mol/L prepared'; other steps were the same as in example 23 to manufacture a battery.

The results of the measurements of the batteries prepared in the above examples 1 to 24 on the cycle number, capacity retention rate, coulombic efficiency and other properties are shown in table 1 below, and the results are analyzed from table 1, in examples 1 to 4, when the concentration of the electrolyte reaches a saturation state, the cycle number reaches 110 times, the capacity retention rate is 93%, and the coulombic efficiency is 83% in the batteries using LiFSI/EC: DMC (1:1) as the electrolyte, expanded graphite as the positive electrode, and a metal lithium foil as the negative electrode; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 30 times, the capacity retention rate is 47%, and the coulombic efficiency is 30%. Further, the battery prepared in example 1 was analyzed for charge and discharge, and as shown in fig. 2, which is a charge and discharge graph, and fig. 3, which is a charge and discharge performance graph, it can be analyzed that the battery prepared in example 1 has a voltage window of 3-5.2v and a current density of 0.4A/g; during the charging and discharging processes, the anion FSI-can be reversibly intercalated and deintercalated in the graphite, and the discharge specific capacity of 100 cycles is maintained at 72mAh/g under the current density of 0.4A/g.

In examples 5 to 8, in a battery using LiFSI/EC: DMC (1:1) as an electrolyte, expanded graphite as a positive electrode, and a metal aluminum foil as a negative electrode, when the concentration of the electrolyte reaches a saturation state, the cycle number reaches 370 times, the capacity retention rate is 92%, and the coulombic efficiency is 80%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 160 times, the capacity retention rate is 48%, and the coulombic efficiency is 30%. Further, when the battery prepared in example 5 was analyzed for charge and discharge, as shown in fig. 4, which is a charge and discharge graph, and fig. 5, which is a charge and discharge performance graph, it was analyzed that the battery prepared in example 5 had a voltage window of 3 to 5.1v and a current density of 0.200A/g. During the charging and discharging process, the negative ions FSI-are reversibly intercalated and deintercalated in the graphite, Li + and the negative electrode are reversibly alloyed and dealloyed, and the discharge specific capacity of 200 cycles is maintained at 60mAh/g under the current density of 0.2A/g.

In examples 9 to 12, when the concentration of the electrolyte reaches a saturation state in a battery using LiFSI/EC: DMC (1:1) as the electrolyte, a ternary material as the positive electrode, and a metal lithium foil as the negative electrode, the cycle number reaches 95 times, the capacity retention rate is 93%, and the coulombic efficiency is 70%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 35 times, the capacity retention rate is 47%, and the coulombic efficiency is 10%. Further, when the battery prepared in example 9 was analyzed for charge and discharge, as shown in fig. 6, which is a charge and discharge graph, and fig. 7, which is a charge and discharge performance graph, it was analyzed that the battery prepared in example 9 had a voltage window of 2.3 to 4.2v and a current density of 0.4 mA/g. In the process of charging and discharging, the anion FSI-is reversibly intercalated and deintercalated in the traditional LiNi0.5Co0.2Mn0.3O2 ternary material, and the discharge specific capacity of about 100 circles of circulation is maintained at about 100mAh/g under the current density of 0.4A/g.

In examples 13 to 16, when the concentration of the electrolyte reaches a saturation state in a battery using LiFSI/EC: DMC (1:1) as the electrolyte, a ternary material as the positive electrode, and a metal aluminum foil as the negative electrode, the cycle number reaches 200 times, the capacity retention rate is 93%, and the coulombic efficiency is 80%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 40 times, the capacity retention rate is 47%, and the coulombic efficiency is 30%. Further, when the battery prepared in example 13 was analyzed for charge and discharge, as shown in fig. 8, which is a charge and discharge graph, and fig. 9, which is a charge and discharge performance graph, it was analyzed that the battery prepared in example 13 had a voltage window of 2.3 to 4.2v and a current density of 50 mA/g. During the charging and discharging processes, the anion FSI-is reversibly intercalated and deintercalated in the traditional LiNi0.5Co0.2Mn0.3O2 ternary material, Li + and the cathode are reversibly alloyed and dealloyed, and the specific discharge capacity can reach 150mAh/g under the current density of 50 mA/g.

In examples 17 to 18, in a battery using NaFSI/EC DMC (1:1) as an electrolyte, expanded graphite as a positive electrode, and a metal tin foil as a negative electrode, when the concentration of the electrolyte reaches a saturation state, the cycle number reaches 320 times, the capacity retention rate is 90%, and the coulombic efficiency is 89%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 50 times, the capacity retention rate is 45%, and the coulombic efficiency is 20%.

In examples 19 to 20, in a battery using NaFSI/EC DMC (1:1) as an electrolyte, expanded graphite as a positive electrode, and a metal antimony foil as a negative electrode, when the concentration of the electrolyte reaches a saturation state, the cycle number reaches 300 times, the capacity retention rate is 92%, and the coulombic efficiency is 87%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 55 times, the capacity retention rate is 44%, and the coulombic efficiency is 26%.

In examples 21 to 22, in a battery using KFSI/EC: DMC (1:1) as an electrolyte, expanded graphite as a positive electrode, and a metal tin foil as a negative electrode, when the concentration of the electrolyte reached a saturated state, the cycle number reached 150 times, the capacity retention rate was 92%, and the coulombic efficiency was 89%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 20 times, the capacity retention rate is 46%, and the coulombic efficiency is 23%.

In examples 23 to 24, in a battery using KFSI/EC: DMC (1:1) as an electrolyte, expanded graphite as a positive electrode, and a metal antimony foil as a negative electrode, when the concentration of the electrolyte reaches a saturation state, the cycle number reaches 140 times, the capacity retention rate is 91%, and the coulombic efficiency is 90%; when the concentration of the electrolyte is only 1mol/L, the cycle frequency is only 15 times, the capacity retention rate is 45%, and the coulombic efficiency is 30%.

TABLE 1

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A novel battery comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, and is characterized in that the molar concentration of the electrolyte is 3 mol/L-saturated concentration; the negative electrode is a metal negative electrode integrating a negative electrode current collector and a negative electrode material.

2. The novel battery according to claim 1, wherein the material of the negative electrode is selected from any one of aluminum, magnesium, zinc, iron, cobalt, nickel, antimony, tin, bismuth, germanium, and alloys thereof.

3. The novel battery of claim 1, wherein the electrolyte comprises an electrolyte salt and a solvent.

4. The novel battery according to claim 3, wherein the electrolyte salt is selected from any one of lithium salt, sodium salt, potassium salt, calcium salt; and/or the presence of a gas in the gas,

the solvent is selected from any one of ester organic solvents, sulfone organic solvents, ether organic solvents and nitrile organic solvents.

5. The novel battery according to claim 4,

the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroarsenate, lithium perchlorate, lithium nitrate, lithium trifluoromethanesulfonate, lithium bis (trifluoromethanesulfonate) imide, lithium bis (fluorosulfonyl) imide and derivatives thereof, lithium perfluoroalkyl phosphate, lithium tetrafluoro oxalate phosphate, lithium bis (oxalato) borate, lithium tris (catechol) phosphate and sulfonated polysulfonamide lithium salt; and/or the presence of a gas in the gas,

the sodium salt is selected from at least one of sodium hexafluorophosphate, sodium fluoborate, sodium hexafluoroarsenate, sodium high aluminate, sodium nitrate, sodium trifluoromethanesulfonate, sodium bis (trifluoromethanesulfonate) imide, sodium bis (fluorosulfonyl) imide and derivatives thereof, sodium bis (oxalato) phosphate, sodium perfluoroalkyl phosphate, sodium tetrafluorooxalato phosphate, sodium tris (catechol) phosphate and sulfonated polysulfonamide lithium; and/or the presence of a gas in the gas,

the potassium salt is at least one selected from potassium hexafluorophosphate, potassium fluoroborate, potassium hexafluoroarsenate, potassium aluminate, potassium nitrate, potassium sulfate, potassium chloride, potassium trifluoromethanesulfonate, potassium bis (trifluoromethanesulfonate) imide, potassium bis (fluorosulfonate) imide and derivatives thereof, potassium dodecylbenzenesulfonate, potassium dodecylsulfate, potassium perfluoroalkyl phosphate, potassium tetrafluorooxalate, potassium tris (catechol) phosphate, sulfonated lithium polysulfonamide, potassium bis (oxalato) borate, potassium difluoro (oxalato) borate, potassium pyrophosphate and potassium citrate; and/or the presence of a gas in the gas,

the calcium salt is selected from at least one of calcium hexafluorophosphate, calcium borate, calcium metaborate, calcium hexafluoroarsenate, calcium perchlorate, calcium tetrafluoroborate, calcium phosphate, calcium nitrate, calcium difluoroborate, calcium pyrophosphate, calcium dodecylbenzenesulfonate, calcium dodecylsulfate, calcium molybdate, calcium tungstate, calcium bromide, calcium oxalate, calcium aluminate, calcium acetate, calcium lignosulfonate, calcium methylsulfonate, calcium trifluoromethanesulfonylimide and calcium trifluoromethanesulfonate.

6. The novel battery according to claim 4, wherein the solvent is selected from at least one of ethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, propylene carbonate, diethyl carbonate, methyl formate, methyl acetate, N-dimethylacetamide, fluoroethylene carbonate, methyl propionate, ethyl acetate, γ -butyrolactone, tetrahydrofuran, 2-methyltetrahydrofuran, 1, 2-dimethoxypropane 1, 3-dioxolane, 4-methyl-1, 3-dioxolane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dimethyl sulfone, sulfolane, dimethyl ether, dimethoxymethane, ethylene sulfite, propylene sulfite, and diethyl sulfite.

7. The novel battery according to any one of claims 1 to 6, wherein the positive electrode comprises a positive electrode current collector and a positive electrode material bonded on the positive electrode current collector, wherein the positive electrode material is selected from any one of lithium cobaltate, lithium iron phosphate, nickel-cobalt-manganese ternary material, flake graphite, mesocarbon microbeads, molybdenum disulfide, activated carbon, porous graphene and array carbon nanotubes; and/or the presence of a gas in the gas,

the positive electrode comprises a positive current collector and a positive material combined on the positive current collector, wherein the positive current collector is selected from any one of aluminum foil, tin foil, magnesium foil, zinc foil, copper foil, iron foil, nickel foil, titanium foil, manganese foil, antimony foil and bismuth foil.

8. The novel battery according to any one of claims 1 to 6, wherein the separator is selected from any one of a multi-glass fiber, a porous polyethylene film, a porous polypropylene film, a porous composite polymer film, a non-woven fabric, and a porous ceramic separator.

9. The novel battery according to any one of claims 1 to 6, wherein the current density for charging and discharging the novel battery is 0.01mA/cm²～5mA/cm²。

10. The preparation method of the novel battery is characterized by comprising the following steps: