CN106887637A - Self-supporting aluminium ion battery and preparation method thereof - Google Patents

Abstract

The invention discloses a self-supporting aluminum ion battery and a preparation method thereof. The self-supporting aluminum ion battery includes a positive pole, a negative pole and an electrolyte, the positive pole has a self-supporting structure without a current collector, the self-supporting structure includes a diaphragm and a conductive carbon material attached to the diaphragm, the electrolyte Selected from non-aqueous electrolyte solutions, the negative electrode includes high-purity aluminum or aluminum alloy. The preparation method includes: depositing a conductive material with good conductivity on the diaphragm, thereby obtaining a positive electrode without a conductive agent and a binder, and further assembling into a self-supporting aluminum ion battery without a current collector. The self-supporting aluminum-ion battery of the invention can greatly reduce the weight of the battery itself, and can significantly improve the performance of the aluminum-ion battery. The preparation process is simple, controllable, economical, and environmentally friendly, and is suitable for large-scale production.

Description

Self-supporting aluminum ion battery and preparation method thereof

technical field

The invention relates to an aluminum ion battery, in particular to a self-supporting aluminum ion battery and a preparation method thereof, belonging to the technical field of energy materials.

Background technique

With the rapid development of science and technology and economy, non-renewable energy sources such as oil, natural gas and coal are increasingly depleted, and the environmental pollution and greenhouse effect caused by them are becoming more and more serious. Therefore, environmental protection and energy crisis are two major problems facing the world today. Effective development and rational use of renewable clean energy has become the focus of research. Lithium-ion batteries are widely used in electronic products, power energy and other fields due to their high energy density and high-voltage platform. Continued development of ion batteries. Therefore, it is particularly important to seek new battery systems that can replace lithium-ion batteries. Because of its abundant reserves and low cost, aluminum has quickly entered the sight of researchers. Compared with lithium ions, aluminum ions can transfer three electrons, so their specific capacity has a greater potential. At the same time, the radius of aluminum ions is smaller than that of lithium ions, which is more conducive to the deintercalation of ions on the electrode material, thereby maintaining the integrity of the electrode structure, improving the cycle stability of the battery, and prolonging the service life of the battery. However, the current manufacturing process of aluminum-ion batteries is still immature. Therefore, optimizing the structure of aluminum-ion batteries is of great significance for improving production efficiency, reducing battery costs and realizing commercial applications.

Contents of the invention

The main purpose of the present invention is to provide a self-supporting aluminum ion battery and a preparation method thereof, so as to improve the performance of the aluminum ion battery, thereby overcoming the deficiencies in the prior art.

In order to achieve the above-mentioned purpose of the invention, the technical scheme adopted in the present invention includes:

An embodiment of the present invention provides a self-supporting aluminum ion battery, including a positive electrode, a negative electrode and an electrolyte, the positive electrode has a self-supporting structure without a current collector, and the self-supporting structure includes a diaphragm and a conductive electrode attached to the diaphragm. carbon material.

Preferably, the electrolyte is selected from nonaqueous electrolytes.

Preferably, the negative electrode includes high-purity aluminum or aluminum alloy.

Preferably, the positive electrode does not contain conductive agent and binder.

Preferably, the conductive carbon material includes any one or a combination of two or more of carbon nanotubes, graphene and conductive polymers, but is not limited thereto.

Further, the electrolytic solution includes an aluminum ion electrolyte, for example, preferably an ionic liquid containing freely movable Al ³⁺ .

Further, the ionic liquid includes 1-butyl-3-methylimidazolium chloride, 1-propyl-3-methylimidazolium chloride and 1-ethyl-3-methylimidazolium chloride Composition of any one or two or more in any proportion, but not limited thereto.

In some preferred embodiments, the aluminum ion electrolyte includes aluminum halide and imidazolium chloride in a molar ratio of 1.1-1.8.

Further, the diaphragm includes any one of ion-permeable polypropylene microporous diaphragm, polyethylene microporous diaphragm and glass fiber material, but is not limited thereto.

The embodiment of the present invention provides a method for preparing the self-supporting aluminum ion battery, which includes:

providing a separator and depositing a conductive carbon material directly on said separator to form a positive electrode having a self-supporting structure;

providing a negative electrode comprising high-purity aluminum or an aluminum alloy;

Provide an ionic liquid containing freely mobile Al ³⁺ as the electrolyte;

The positive electrode, negative electrode and electrolyte are assembled to form a self-supporting aluminum ion battery.

Further, the preparation method includes: directly depositing a conductive carbon material on the separator by physical or chemical methods to form the positive electrode.

Further, the preparation method includes: completing the encapsulation of the self-supporting aluminum ion battery in an environment of H ₂ O<1ppm and O ₂ <1ppm.

In a novel aluminum ion battery structure provided by the present invention, no conductive agent, binder and current collector are needed in the positive electrode, which greatly reduces the weight of the battery, optimizes the production process, reduces the production cost, and greatly improves the performance of the battery At the same time, the positive electrode is formed by combining the conductive carbon material and the diaphragm. Due to the good conductive structure of the tubular, sheet or mesh conductive carbon material, it provides a fast channel for the insertion and deintercalation of ions, and provides conductivity itself. The diaphragm used has good insulation, good permeability to electrolyte ions, corrosion resistance, certain chemical and electrochemical stability, and sufficient mechanical properties; and the use of ionic liquids containing aluminum ions as electrolytes, It has the characteristics of high electrical conductivity, wide potential window, and good thermal and chemical stability.

In a word, compared with the prior art, the advantages of the present invention include: the self-supporting aluminum ion battery provided can greatly reduce the weight of the battery itself, and can significantly improve the performance of the aluminum ion battery, and its preparation process is simple, controllable, economical and environmentally friendly Friendly and suitable for mass production.

Description of drawings

Fig. 1 is the charge-discharge curve diagram of the self-supporting aluminum ion battery prepared in embodiment 1;

Fig. 2 is the cycle performance test curve figure of the self-supporting aluminum-ion battery prepared in embodiment 1;

FIG. 3 is a Coulombic efficiency diagram of the self-supporting aluminum ion battery prepared in Example 1. FIG.

detailed description

One aspect of the present invention provides a novel hypervalent ion battery, which is a self-supporting aluminum ion battery based on an intercalation and deintercalation mechanism, which includes a positive electrode, a negative electrode, an electrolyte, and a separator, wherein the positive electrode includes a separator and is attached to Tubular, sheet or mesh conductive carbon material on the diaphragm, the negative electrode is high-purity aluminum or aluminum alloy.

In other words, in the aluminum ion battery of the present invention, the positive electrode and the separator are of an integrated structure.

Wherein, the conductive carbon material, diaphragm, electrolyte, etc. may be selected from various types listed above, and will not be repeated here.

Wherein, the positive electrode does not need to include any current collector, for example, it does not need to use stainless steel foil or nickel foam known in the industry.

Wherein, the positive electrode does not need to contain conductive agents, binders, etc., for example, it is not necessary to use conductive agents such as acetylene black, super carbon, carbon nanotubes, and for example, it is not necessary to use non-binding agents such as polytetrafluoroethylene or polyvinylidene fluoride. .

One aspect of the present invention provides a method of preparing the self-supporting aluminum ion battery. For example, in one embodiment, the preparation method includes the following steps:

1) directly depositing the conductive carbon material on the separator as the positive electrode;

2) Cleaning high-purity aluminum (purity above 99.9%) or aluminum alloy as negative electrode;

3) Configure an aluminum-containing ionic liquid as the electrolyte;

4) Packaging the positive electrode, negative electrode and electrolyte in a glove box (H ₂ O<1ppm, O ₂ <1ppm) to form the self-supporting aluminum ion battery.

Further, in the above step 1), the deposition method of the conductive polymer and the diaphragm can be compounded by chemical or physical methods, such as suction filtration, spin coating, physical deposition, dipping, sputtering, etc., but not limited thereto.

Further, in the above step 2), the cleaning method of the negative electrode may include: first soaking in dilute hydrochloric acid for 1-5 minutes, then ultrasonically using acetone or ethanol for 30-90 minutes, and vacuum drying.

The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings and several preferred embodiments.

Example 1 1 mg of polyaniline (PAN) hydrogel was ultrasonically dispersed in deionized water, then suction-filtered on a glass fiber (GF/A, whatman) diaphragm with a diameter of 20 mm, and vacuum-dried at 100 ° C for 12 hours, as a non-current collector Self-supporting positive pole. Soak high-purity aluminum foil in hydrochloric acid for 1 to 5 minutes, and dry it after ultrasonication in acetone for 30 to 90 minutes, as a negative electrode. Aluminum chloride and 1-ethyl-3-methylimidazolium chloride were synthesized into ionic liquid at a molar ratio of 1.1:1 as the electrolyte. The 2032-type button battery was packaged in a glove box (H ₂ O<1ppm, O ₂ <1ppm). After the battery was left to stand for 12 hours, the charge and discharge test was carried out at 0.02-2.5V. The results can be seen in Figures 1-3.

Example 2 Ultrasonic dispersion of 1 mg of polyaniline airgel in absolute ethanol was then suction-filtered on a glass fiber (GF/A, whatman) diaphragm with a diameter of 20 mm, and vacuum-dried at 100°C for 12 hours as a self-supporting airgel without a current collector. positive pole. Soak the high-purity aluminum foil in hydrochloric acid for 1-5 minutes, and dry it after ultrasonication in acetone for 30-90 minutes, as the negative electrode. Aluminum chloride and 1-ethyl-3-methylimidazolium chloride were synthesized as electrolytes in a molar ratio of 1.3:1. A 2032-type button battery was packaged in a glove box (H ₂ O<1ppm, O ₂ <1ppm). After the battery was left to stand for 12 hours, a charge-discharge test was performed at 0.02-2.5V. The test results were similar to those in Example 1.

The preparation process of the self-supporting aluminum ion battery of the present invention is simple, safe and low in cost, and can be extended to the preparation of other hypervalent ion batteries, and has great value for the commercialization of the aluminum ion battery.

It should be understood that the above examples are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. a kind of self-supporting aluminium ion battery, including positive pole, negative pole and electrolyte, it is characterised in that described just to have without afflux The self supporting structure of body, the self supporting structure includes barrier film and the conductive carbon material being attached on the barrier film, the electrolysis Liquid is selected from nonaqueous electrolytic solution, and the negative pole includes high-purity aluminum or aluminum alloy.

2. self-supporting aluminium ion battery according to claim 1, it is characterised in that：The positive pole is free of conductive agent and bonding Agent.

3. self-supporting aluminium ion battery according to claim 1, it is characterised in that：The conductive carbon material includes carbon nanometer Any one in pipe, Graphene and conducting polymer or two or more combinations.

4. self-supporting aluminium ion battery according to claim 1, it is characterised in that：The barrier film includes having ion penetrating Any one in the polypropylene micropore diaphragm of property, polyethylene micropore barrier film and glass fiber material.

5. self-supporting aluminium ion battery according to claim 1, it is characterised in that：The electrolyte is electrolysed including aluminium ion Matter, the aluminium ion electrolyte can move freely Al including containing³⁺Ionic liquid.

6. self-supporting aluminium ion battery according to claim 5, it is characterised in that：The ionic liquid includes 1- butyl -3- Any one or two kinds of methylimidazole chlorate, 1- propyl group -3- methylimidazoles chlorate and 1- ethyl-3-methylimidazole chlorates with On composition in any proportion.

7. self-supporting aluminium ion battery according to claim 4, it is characterised in that：The aluminium ion electrolyte include mole Than the aluminum halide for 1.1~1.8 and imidazoles chlorate.

8. as any one of claim 1-7 self-supporting aluminium ion battery preparation method, it is characterised in that including：

Barrier film is provided, and conductive carbon material is deposited directly on the barrier film, form the positive pole with self supporting structure；

Negative pole is provided, the negative pole includes high-purity aluminum or aluminum alloy；

There is provided and contain the Al that can move freely³⁺Ionic liquid as electrolyte；

The positive pole, negative pole and electrolyte are assembled to form self-supporting aluminium ion battery.

9. preparation method as claimed in claim 8, it is characterised in that including：Using either physically or chemically by conductive carbon material It is deposited directly on the barrier film and forms the positive pole；The chemically or physically method include suction filtration, spin coating, physical deposition, Any one in dipping, sputtering mode or two or more combinations.

10. preparation method as claimed in claim 8, it is characterised in that including：In H₂O<1ppm、O₂<The environment of 1ppm The middle encapsulation for completing the self-supporting aluminium ion battery.