CN108711636B - Combined electrolyte type dual-ion rocking chair type secondary battery and preparation method thereof - Google Patents

Abstract

The invention discloses a combined electrolyte type dual-ion rocking chair type secondary battery and a preparation method thereof, belonging to the technical field of electrochemical storage. The battery of the present invention includes a positive electrode, a negative electrode, a diaphragm and an electrolyte, the electrolyte includes a positive electrode electrolyte and a negative electrode electrolyte, the positive electrode electrolyte is an ionic liquid containing an alkali metal salt, and the negative electrode electrolyte is an ether organic compound containing the same alkali metal salt. Solvent; the positive and negative electrodes are separated by a diaphragm, and the corresponding positive electrolyte and negative electrolyte are dropped on both sides of the diaphragm respectively. The invention also provides a method for preparing the battery, which includes the following steps: processing the positive electrode material, the negative electrode material and the diaphragm into a sheet shape; adding the positive electrode electrolyte and the negative electrode electrolyte dropwise on both sides of the diaphragm to obtain a combined electrolyte type dual Ion rocking chair type secondary battery. The combined electrolyte type dual-ion rocking-chair type secondary battery of the present invention can simultaneously exert the advantages of the positive electrode electrolyte and the negative electrode electrolyte, thereby greatly improving the cycle stability of the battery.

Description

A combined electrolyte type dual ion rocking chair type secondary battery and preparation method thereof

technical field

The invention relates to a combined electrolyte type dual-ion rocking chair type secondary battery and a preparation method thereof, belonging to the technical field of electrochemical storage.

Background technique

Lithium-ion battery is one of the most important energy storage devices in the world today. It deintercalates lithium ions as a carrier for charge transport between positive and negative materials, so as to achieve electrical energy storage and release. It has high energy density and high power density. As well as the advantages of high working voltage, it has broad application prospects in large-scale energy storage and transportation industries. Lithium, the key raw material for lithium-ion batteries, has only 0.065% reserves in the earth's crust and is unevenly distributed, mainly concentrated in South America. With the development of the world economy, the demand for lithium resources in human life and production will continue to increase. It is foreseeable that the price of lithium resources will continue to rise, which will lead to difficult and expensive applications of various lithium electronic equipment. Therefore, it is very urgent to develop new energy storage devices to replace lithium-ion battery energy storage devices. Compared with lithium-ion batteries, yin-yang dual-ion rocking-chair batteries are considered to be the most promising due to the advantages of high output voltage, environmental friendliness, and low price through de-intercalation between positive and negative electrode materials through the use of anion and anion ions as carriers. One of the next generation of new energy storage devices. However, during the de-intercalation process of the positive reactive anion in the yin-yang dual-ion rocking-chair battery, the reaction potential is about 5V. At such a high potential, the traditional organic electrolyte will undergo severe oxidative decomposition, which will lead to the stability of the battery. Efficiency drops sharply. Therefore, some scientists have recently tried to use ionic liquids with good antioxidant properties as battery electrolytes. The research results show that the use of ionic liquids can effectively inhibit the decomposition of electrolytes and improve the positive performance of batteries. Although this move can well ensure the positive electrode reaction of the battery, it also brings some series of problems, especially the use of ionic liquid electrolyte, which will affect the production of unstable solid electrolyte film on the surface of the negative electrode material, resulting in serious side reactions of the negative electrode, which greatly Reduce battery coulombic efficiency and affect battery cycle stability. How to effectively design the positive and negative reactions of the yin-yang dual-ion rocker battery to ensure the advantages of high output voltage, environmental friendliness and low cost of the yin-yang dual-ion rocker battery, and promote its commercialization has always been a difficult problem for scientists.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned technical problems, the purpose of the present invention is to provide a combined electrolyte type dual ion rocking chair type secondary battery and a preparation method thereof. The combined electrolyte type dual ion rocking chair type secondary battery of the present invention uses ions in the positive electrode reaction. The liquid is the electrolyte to ensure that the electrolyte is not decomposed under high working voltage. In the negative electrode reaction, ether organic solvent is used as the electrolyte to ensure the coulombic efficiency of the negative electrode, and the advantages of the positive electrode electrolyte and the negative electrode electrolyte can be exerted at the same time. Improve the cycle stability of the battery.

The first object of the present invention is to provide a dual-ion rocking chair type secondary battery, comprising a positive electrode material, a negative electrode material, a diaphragm and an electrolyte, and the electrolyte is a combined electrolyte, including a positive electrolyte and a negative electrolyte, The positive electrode electrolyte is an ionic liquid containing an alkali metal salt, and the negative electrode electrolyte is an ether organic solvent containing the same alkali metal salt.

In one embodiment of the present invention, the anions in the ionic liquid are the same as the anions in the alkali metal salt.

In one embodiment of the present invention, the cation in the alkali metal salt is selected from Li ⁺ , Na ⁺ or K ⁺ , and the anion in the alkali metal salt is selected from bis(trifluoromethane)sulfonimide , bis(fluorosulfonyl)imide, trifluoromethanesulfonate or hexafluorophosphate.

In one embodiment of the present invention, the cation in the ionic liquid is selected from 1-methyl-1-propylpyrrolidine ion, 1-ethyl-3-methylimidazolium ion, N-trimethoxysilicon ion propylpropyl-N,N,N-trimethylcation or N,N-dialkylpyrrolidinium ion.

In one embodiment of the present invention, the ionic liquid is 1-methyl-1-propylpyrrolidine bis(trifluoromethane)sulfonimide, 1-ethyl-3-methylimidazole bis(trifluoromethane) Fluoromethane)sulfonimide, N-trimethoxysilylpropyl-N,N,N-trimethylbis(trifluoromethane)sulfonimide, N,N-dialkylpyrrolidinium bis( trifluoromethane)sulfonimide, 1-methyl-1-propylpyrrolidine bis(fluorosulfonyl)imide, 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide, N- Trimethoxysilylpropyl-N,N,N-trimethylbis(fluorosulfonyl)imide, N,N-dialkylpyrrolidinium bis(fluorosulfonyl)imide, 1-methyl- 1-Propylpyrrolidine trifluoromethanesulfonic acid, 1-ethyl-3-methylimidazole trifluoromethanesulfonic acid, N-trimethoxysilylpropyl-N,N,N-trimethyltrifluoromethane Sulfonic acid, N,N-dialkylpyrrolidinium trifluoromethanesulfonic acid, 1-methyl-1-propylpyrrolidine hexafluorophosphoric acid, 1-ethyl-3-methylimidazolium hexafluorophosphoric acid, N- Trimethoxysilylpropyl-N,N,N-trimethylhexafluorophosphoric acid or N,N-dialkylpyrrolidinium hexafluorophosphoric acid.

In one embodiment of the present invention, the alkali metal salt is lithium bis(trifluoromethane)sulfonimide, lithium bis(fluorosulfonyl)imide, lithium trifluoromethanesulfonate, lithium hexafluorophosphate, lithium bis(trifluoromethane) Sodium fluoromethane)sulfonimide, sodium bis(fluorosulfonyl)imide, sodium trifluoromethanesulfonate, sodium hexafluorophosphate, potassium bis(trifluoromethane)sulfonimide, bis(fluorosulfonyl)idene Potassium amine, potassium triflate or potassium hexafluorophosphate.

In one embodiment of the present invention, the ether organic solvent is one of diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether and pentaethylene glycol dimethyl ether or several.

In one embodiment of the present invention, the concentration of the positive electrode electrolyte is 0.1-10 mol L ⁻¹ . Preferably, the concentration of the electrolyte solution is 1.5 mol L ⁻¹ .

In one embodiment of the present invention, the concentration of the negative electrode electrolyte is 0.1-10 mol L ⁻¹ . Preferably, the concentration of the electrolyte solution is 2.75 mol L ⁻¹ .

In an embodiment of the present invention, the positive electrode material is a carbon material.

In one embodiment of the present invention, the carbon material is graphite, mesoporous carbon, hard carbon or soft carbon.

In one embodiment of the present invention, the positive electrode material further includes a binder.

In one embodiment of the present invention, the binder is one or more of polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethyl cellulose, polyolefin, SBR rubber, fluorinated rubber and polyurethane kind.

In an embodiment of the present invention, the negative electrode material is carbon material or metallic lithium, metallic sodium, metallic potassium, silicon, tin, aluminum, phosphorus or lithium titanate.

In one embodiment of the present invention, the carbon material is graphite, mesoporous carbon, hard carbon or soft carbon.

In an embodiment of the present invention, when the negative electrode material is a carbon material, the negative electrode material further includes a binder.

In an embodiment of the present invention, the binder is one or more of polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethyl cellulose, polyolefin, SBR rubber, fluorinated rubber and polyurethane.

In one embodiment of the present invention, when the negative electrode material is silicon, tin, aluminum, phosphorus or lithium titanate, the negative electrode material further includes a conductive agent and a binder.

In one embodiment of the present invention, the conductive agent is one or more of acetylene black, SPUER P, carbon black, Ketjen black, conductive graphite, carbon fiber, carbon nanotube and graphene.

In an embodiment of the present invention, the binder is one or more of polyvinylidene fluoride, polytetrafluoroethylene, sodium carboxymethyl cellulose, polyolefin, SBR rubber, fluorinated rubber and polyurethane.

In one embodiment of the present invention, the separator is a Nafion film, a lithiated Nafion film, or a potassium-based Nafion film.

In one embodiment of the present invention, the positive electrode material and the negative electrode material of the dual-ion rocking-chair secondary battery are both carbon materials, the diaphragm is a Nafion film, and the electrolyte includes a positive electrode electrolyte and a negative electrode electrolyte. Separated by a diaphragm, the corresponding positive and negative electrolytes are added dropwise on both sides of the diaphragm.

The second object of the present invention is to provide the preparation method of the described dual-ion rocking chair type secondary battery, comprising the following steps:

(1) Process the positive electrode material, negative electrode material and separator into sheets;

(2) A separator is placed between the positive electrode material and the negative electrode material, and the positive electrode electrolyte and the negative electrode electrolyte are respectively added on both sides of the separator to obtain the dual-ion rocking chair type secondary battery.

In an embodiment of the present invention, the method further includes the step of mixing the positive electrode material and the binder and coating the aluminum foil or copper foil as a positive electrode.

In an embodiment of the present invention, the method further includes the step of mixing the negative electrode material and the binder and then coating the aluminum foil or copper foil as a negative electrode.

In one embodiment of the present invention, the positive electrode material or the negative electrode material is processed into a disc with a diameter of 6-18 mm.

In an embodiment of the present invention, the concentrations of the positive and negative electrolytes are 0.1-10 mol L ^-1 . The volume of positive and negative electrolytes is 0.01-0.5 mL.

The beneficial effects of the present invention are: (1) the combined electrolyte type dual-ion rocking chair type secondary battery of the present invention, for different positive and negative reactions, an ionic liquid with good oxidation resistance is selected as the positive electrode reaction electrolyte to ensure electrolysis under high pressure. The solution is not oxidized and decomposed, and an ether-based organic solvent that stabilizes the solid electrolyte membrane is selected as the negative electrode reaction electrolyte to ensure the high coulombic efficiency of the battery. The use of this combined electrolyte can give full play to the advantages of the positive and negative electrolytes at the same time, ensuring the electrolyte. This type of rocking-chair secondary battery can cycle stably for more than 3000 cycles at a current density of 100mA g ^-1 .

(2) The combined electrolyte type dual-ion rocking chair type secondary battery of the present invention has a working voltage of up to 4.2V, has a coulombic efficiency of up to 99.7%, and can use the same amount of positive and negative active materials, reducing the waste of active materials and reducing battery cost.

(3) The combined electrolyte type dual-ion rocking-chair secondary battery of the present invention has ultra-high cycle stability, high Coulombic efficiency and high working voltage, and has broad application prospects in the field of power batteries in the future.

Description of drawings

Fig. 1 is the model diagram of the combined electrolyte type dual ion rocking chair type secondary battery of the present invention;

Fig. 2 is the charge-discharge curve diagram of the combined electrolyte type dual-ion rocking chair type secondary battery made in Example 1 of the present invention;

3 is a cycle stability diagram of a combined electrolyte type dual-ion rocking chair type secondary battery made in Example 1 of the present invention;

Figure 4 is a double-ion rocking chair formula of 1-methyl-1-propylpyrrolidine bis(trifluoromethanesulfonyl)imide salt solution using 1.5mol L ^-1 lithium bis(trifluoromethane)sulfonimide alone The charge-discharge curve of the secondary battery;

Figure 5 is a double-ion rocking-chair formula of 1-methyl-1-propylpyrrolidine bis(trifluoromethanesulfonyl)imide salt solution using 1.5mol L ^-1 lithium bis(trifluoromethane)sulfonimide alone Cycling stability diagram of the secondary battery.

Detailed ways

The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

Example 1:

(1) Prepare battery materials according to the following formula:

Positive electrode material: all in mass fraction, it includes 90% graphite, 10% polyvinylidene fluoride binder.

Negative electrode material: all in mass fraction, it includes 90% graphite, 10% polyvinylidene fluoride binder.

Battery separator: lithiated Nafion membrane.

Positive electrolyte: 1.5 mol L ^-1 bis(trifluoromethanesulfonyl)imide salt solution of lithium bis(trifluoromethane)sulfonimide in 1-methyl-1-propylpyrrolidine bis(trifluoromethanesulfonyl)imide.

Negative Electrolyte: 2.75mol L ^-1 triethylene glycol dimethyl ether solution of lithium bis(trifluoromethane)sulfonimide.

The positive electrode material is mixed with a binder and then coated on copper foil or aluminum foil to serve as a positive electrode. The above electrodes were cut into discs with a diameter of 12 mm.

The negative electrode material is mixed with a binder and then coated on copper foil or aluminum foil to serve as a negative electrode. The above electrodes were cut into discs with a diameter of 12 mm.

The lithiated Nafion films were cut into 19 mm diameter discs.

(2) Assemble the CR2032 button battery in the argon gas glove box, and the related accessories of the battery case (negative electrode case, shrapnel, gasket, positive electrode case) are all made of stainless steel. The above battery materials are assembled in the following order: negative electrode shell, shrapnel, gasket, negative sodium sheet, diaphragm, positive electrode and positive electrode shell, and 0.05 mL of the corresponding positive and negative electrolytes are added dropwise on both sides when the diaphragm is added. The button-type battery sealing machine is pressed to form a combined electrolyte rocking chair type secondary battery. After the battery is installed, perform a charge and discharge test.

The electrochemical performance of the combined electrolyte type dual-ion rocking-chair secondary battery prepared above was tested, and the results are shown in Figure 2 and Figure 3 . It can be seen from Figure 2 that the average voltage of the battery is as high as 4.2V, with high Coulomb efficiency, and the shape of the charge-discharge curve does not change significantly after 3 cycles. It can be seen from Figure 2 that the battery has ultra-long cycle stability. At a current density of 50mA g ^-1 , the battery can cycle stably for 1200 cycles, and at a current density of 100mA g ^-1 , the battery can cycle stably for more than 3000 cycles without obvious decay, and the Coulombic efficiency is as high as 99.7%. These results indicate that the combined electrolyte type dual-ion rocking-chair secondary battery produced in Example 1 does have high working voltage and ultra-long cycle stability.

Example 2:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution is 2.75 mol L ^-1 of lithium bis(fluorosulfonyl)imide in triethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 3:

The positive electrolyte in step (1) was replaced with N-trimethoxysilylpropyl-N,N,N-trimethyltrifluoromethanesulfonic acid solution of 1.5mol L ^-1 lithium trifluoromethanesulfonate , the negative electrode solution is 2.75 mol L ^-1 lithium trifluoromethanesulfonate triethylene glycol dimethyl ether solution. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 4:

The positive electrolyte in step (1) is replaced with the N,N-dialkylpyrrolidinium hexafluorophosphoric acid solution of 1.5mol L- ¹ lithium hexafluorophosphate, and the negative electrode solution is 2.75mol L ^-1 triethylene hexafluorophosphate lithium Glycol ether solution. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 5:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 sodium bis(fluorosulfonyl)imide, negative electrode The solution was 2.75 mol L ^-1 of sodium bis(fluorosulfonyl)imide in triethylene glycol dimethyl ether, and the diaphragm in step (1) was replaced with a Nafion membrane. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was made

Example 6:

The positive electrolyte in the step (1) was replaced with the N,N-dialkylpyrrolidinium hexafluorophosphoric acid solution of 1.5mol L- ¹ of potassium hexafluorophosphate, and the negative electrode solution was 2.75mol L ^-1 of hexafluorophosphate Triethylene glycol dimethyl ether solution of potassium phosphate, replace the diaphragm of step (1) with potassium Nafion membrane. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 7:

The positive electrolyte in step (1) was replaced with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 10mol L ^-1 lithium bis(fluorosulfonyl)imide, and the negative electrode solution It is 2.75mol L ^-1 of bis(fluorosulfonyl)imide lithium solution in triethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 8:

Replace the positive electrolyte in step (1) with 0.1mol L ^-1 of 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of lithium bis(fluorosulfonyl)imide, negative electrode The solution is 2.75 mol L ^-1 of lithium bis(fluorosulfonyl)imide in triethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 9:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution was 2.75 mol L ^-1 of lithium bis(fluorosulfonyl)imide in tetraethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 10:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution was 2.75 mol L ^-1 of lithium bis(fluorosulfonyl)imide in diethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 11:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution was 2.75 mol L ^-1 of lithium bis(fluorosulfonyl)imide in pentaethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 12:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution was 10 mol L ^-1 triethylene glycol dimethyl ether solution of lithium bis(fluorosulfonyl)imide. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 13:

Replace the positive electrolyte in step (1) with 1-ethyl-3-methylimidazole bis(fluorosulfonyl)imide solution of 1.5mol L ^-1 lithium bis(fluorosulfonyl)imide, negative electrode The solution is 0.1 mol L ^-1 of lithium bis(fluorosulfonyl)imide in triethylene glycol dimethyl ether. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 14:

Replace the positive electrode material in step (1) with hard carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 15:

Replace the positive electrode material in step (1) with soft carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 16:

Replace the cathode material in step (1) with mesoporous carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 17:

Replace the negative electrode material in step (1) with hard carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 18:

Replace the negative electrode material in step (1) with soft carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 19:

Replace the cathode material in step (1) with mesoporous carbon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 20:

Replace the negative electrode material in step (1) with silicon. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 21:

Replace the negative electrode material in step (1) with tin. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 22:

Replace the negative electrode material in step (1) with aluminum. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 23:

Replace the negative electrode material in step (1) with phosphorus. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Example 24:

Replace the negative electrode material in step (1) with lithium titanate. According to the method of steps (1)-(2) in Example 1, a combined electrolyte type dual-ion rocking-chair secondary battery was fabricated.

Comparative ratio:

The negative electrolyte in step (1) in Example 1 was replaced with 1-methyl-1-propylpyrrolidine bis(trifluoromethanesulfonic acid) of 1.5mol L ^-1 bis(trifluoromethane) sulfonimide lithium The acyl)imide salt solution adopts the same electrolyte as the positive electrode electrolyte, and then according to the method of steps (1)-(2) in Example 1, a dual-ion rocking chair type secondary battery is produced.

The electrochemical performance test of the combined electrolyte type dual-ion rocking-chair secondary battery made above is carried out. The results are shown in Figure 4 and Figure 5. As can be seen from Figure 5, the first cycle specific capacity in the comparative example is only 11mAh/g, and in After 20 cycles of battery cycle, the specific capacity is close to 0mAh/g. The main reason is that the Coulomb efficiency of the first cycle in the comparative example is only 20%, resulting in a rapid decay of its specific capacity.

The above-mentioned embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. The protection scope of the present invention is subject to the claims.

Claims (8)

1. A dual-ion rocking chair type secondary battery comprises a positive electrode material, a negative electrode material, a diaphragm and electrolyte, and is characterized in that the electrolyte comprises positive electrode electrolyte and negative electrode electrolyte, the positive electrode electrolyte is ionic liquid containing alkali metal salt, and the negative electrode electrolyte is an ether organic solvent containing the same alkali metal salt as that in the positive electrode electrolyte;

the ether organic solvent is one or more of diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether and pentaethylene glycol dimethyl ether;

the diaphragm is a Nafion film, a lithiated Nafion film or a potassified Nafion film.

2. The bi-ion rocking chair type secondary battery according to claim 1, wherein the anion in the ionic liquid is the same as the anion in the alkali metal salt.

3. The bi-ion rocking chair type secondary battery according to claim 1, wherein the cation in the alkali metal salt is selected from Li⁺、Na⁺Or K⁺Wherein the anion in the alkali metal salt is selected from bis (trifluoromethane) sulfonimide, bis (fluorosulfonyl) imide, trifluoromethanesulfonate or hexafluorophosphate.

4. The bi-ion rocking chair type secondary battery according to claim 1, wherein the cation in the ionic liquid is selected from 1-methyl-1-propyl pyrrolidine ion, 1-ethyl-3-methylimidazole ion, N-trimethoxysilylpropyl-N, N-trimethyl cation or N, N-dialkylpyrrolidinium ion.

5. The bi-ion rocking chair type secondary battery according to claim 1, wherein the positive electrode material is a carbon material.

6. The bi-ion rocking chair type secondary battery according to claim 1, wherein the negative electrode material is a carbon material, metallic lithium, metallic sodium, metallic potassium, silicon, tin, aluminum, phosphorus, or lithium titanate.

7. The bi-ion rocking chair type secondary battery according to claim 5 or 6, wherein the carbon material is graphite, mesoporous carbon, hard carbon or soft carbon.

8. A method for manufacturing the bi-ion rocking chair type secondary battery of claim 1, comprising the steps of:

(1) processing the positive electrode material, the negative electrode material and the diaphragm into sheets;

(2) and (3) placing a diaphragm between the anode material and the cathode material, and adding the anode electrolyte and the cathode electrolyte on two sides of the diaphragm respectively to obtain the dual-ion rocking chair type secondary battery.

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