CN102903917B - Aqueous electrolyte rechargeable zinc ion battery - Google Patents

Abstract

The invention discloses an aqueous electrolyte rechargeable zinc ion battery, belonging to the technical field of battery preparation. The battery disclosed herein is characterized in that: the cathode active material mainly comprises zinc ions (Zn<2+>)- intercalated and -removed copper (nickel) ferricyanide, the anode active material mainly comprises zinc, and the electrolyte which is liquid or gel comprises soluble salts of zinc as the solute and water as the solvent. According to the invention, the zinc ions can be intercalated in the copper (nickel) ferricyanide cathode material lattices or be removed from the copper (nickel) ferricyanide cathode material lattices, simultaneously the anode material mainly comprising zinc is subject to oxidation or reduction, thus the battery has the characteristics of high specific capacity and rapid charging, and the battery can be widely applied in the fields of portable mobile terminal, equipment, miniature electric vehicle and automobile starting battery, etc.

Description

An aqueous electrolyte rechargeable zinc-ion battery

technical field

The invention belongs to the technical field of battery preparation, and in particular relates to a rechargeable zinc-ion battery with aqueous electrolyte.

Background technique

With the rapid development of the global economy, the supply of fossil fuels and environmental issues have become increasingly prominent. Therefore, the comprehensive and efficient development and utilization of new green energy has become a key link to ensure the security of national energy resources and implement the national energy sustainable development strategy. Compared with primary batteries, secondary batteries can repeat charge and discharge cycles many times and can make full use of raw materials, so they are more economical and practical. The most widely used rechargeable battery is the lithium-ion battery. Lithium-ion batteries use lithium ions as an energy storage medium to store electrical energy, and the charging and discharging of the battery is realized through the intercalation and extraction of lithium ions between the positive and negative electrode materials. With the development of human society and the advancement of science and technology, the types and quantities of mobile electronic products and electric vehicles will continue to increase, and the demand for secondary batteries will also increase. Therefore, it is very necessary and valuable to develop new rechargeable batteries. significant.

Zinc is an active metal, which is cheap, easy to obtain, and safe to process. Therefore, secondary batteries using zinc metal as anode materials have received more and more attention. Chinese invention patent application CN101540417A disclosed for the first time a rechargeable zinc-ion battery with manganese dioxide as the positive electrode, zinc as the negative electrode, and a solution containing zinc ions as the electrolyte. The liquid is then deposited on the negative electrode, where a reversible reaction occurs when discharged. Since zinc and zinc ions are used as active materials, the electrode reaction is a two-electron reaction, and this battery has a high specific capacity. However, due to the small lattice constant of manganese dioxide, the intercalation and deintercalation of zinc ions is relatively difficult, resulting in a slow rate of intercalation and deintercalation of zinc ions in the battery during charging/discharging, so that the performance of zinc ion batteries needs to be further improved.

Therefore, in order to further improve the performance of rechargeable zinc-ion batteries, it is an important technical direction to further improve the performance of rechargeable zinc-ion batteries to find new positive electrode materials that have good intercalation/extraction performance for zinc ions, are inexpensive, and have a wide range of sources.

Contents of the invention

The object of the present invention is to provide an aqueous electrolyte rechargeable zinc ion battery.

An aqueous electrolyte rechargeable zinc-ion battery, the battery is composed of a positive electrode, a negative electrode, a diaphragm material between the former two, and an electrolyte with ion conductivity; wherein the positive electrode includes a current collector and a positive electrode active material on the current collector , the negative electrode includes a current collector and the negative active material on the current collector; the positive active material is KMFe (CN) ₆ film material made of powder, electronic conductive agent and binder; the negative active material is zinc powder, corrosion inhibitor, A film-like material made of electronic conductive agent and binder; the electrolyte is an ion-conductive liquid or gel-state material with zinc soluble salt as the solute and water as the solvent, and its pH value is between 4 and 7.

M in KMFe(CN) ₆ is Cu or Ni element.

The addition amounts of the electronic conductive agent and the binder in the positive electrode active material are respectively less than 10% of the mass of the positive electrode active material.

The addition amount of the corrosion inhibitor in the negative electrode active material is less than 1% of the mass of the negative electrode active material, and the addition amounts of the electronic conductive agent and the binder are respectively less than 10% of the mass of the negative electrode active material.

The above-mentioned electrode conductive agent is graphite, carbon black, acetylene black, carbon nanofiber or carbon nanotube.

The above-mentioned corrosion inhibitor is oxide or hydroxide of indium or copper.

The above binder is polytetrafluoroethylene, polytetrafluoroethylene or cellulose.

The above-mentioned soluble salt of zinc is zinc nitrate, zinc sulfate or zinc chloride.

The battery structure of the rechargeable zinc ion battery proposed by the present invention can be a button type, a cylindrical type or a square structure.

The beneficial effects of the invention are as follows: 1) Zinc metal is used as the negative electrode of the battery, which has high activity, low cost, easy availability and no pollution; 2) The use of insoluble ferricyanide as the positive electrode material is cheap and the preparation process is simple; 3) The use of The aqueous solution of zinc ions is used as the electrolyte, which is easy to prepare, non-flammable, and non-toxic; 4) The rechargeable zinc ion battery of the present invention utilizes the reversible insertion or extraction of zinc ions in the lattice of the positive electrode material, and at the same time, the negative electrode mainly composed of zinc element The energy storage mechanism of material oxidation or zinc ion reduction on the surface of the negative electrode, and the use of a special electrolyte, the battery has the characteristics of high specific capacity and fast charging, and it has the advantages of simple manufacturing process, low cost, and long cycle life. .

Description of drawings

Figure 1 is the cyclic voltammogram of copper ferricyanide electrode in 1mol L ^-1 ZnSO ₄ electrolyte.

Figure 2 is the first charge-discharge curve of the rechargeable Zn-ion battery at a current density of 200 mAg ^-1 .

Figure 3 is the cycle charge and discharge curves of the rechargeable zinc-ion battery at a current density of 200 mAg ^-1 .

Figure 4 is the charge-discharge curve of the rechargeable zinc-ion battery at a current density of 150 mAg ^-1 .

Detailed ways

Example 1

Preparation of Copper Ferricyanide KCuFe(CN) ₆

Add a certain concentration of copper sulfate (copper chloride, zinc sulfate, zinc chloride, nickel sulfate, nickel chloride, etc.) solution and the same concentration of potassium ferricyanide solution drop by drop into continuously stirring deionized water, and wait After completion, ultrasonically shake the suspension mixed with brown precipitate for 30 minutes, then let it stand for 8 hours, then filter out the precipitate, wash it repeatedly with deionized water, and dry it in an oven to obtain ferricyanide copper powder.

Copper ferricyanide, electronic conductive graphite powder and binder polyvinylidene fluoride are evenly mixed in a mass ratio of 18:1:1, and then coated on the carbon current collector, cut into a certain size, and dried in an oven A copper ferricyanide electrode sheet was prepared. The single-electrode test uses copper ferricyanide electrode as the working electrode, a metal platinum electrode as the auxiliary electrode, and a saturated calomel electrode as the reference electrode for detection. The cyclic voltammogram of copper ferricyanide electrode in 1mol L ^-1 ZnSO ₄ aqueous solution is shown in Figure 1. The scan rate is 10mV s ^-1 . It can be seen that there is an oxidation peak and a reduction peak, corresponding to the zinc ion Extraction and intercalation in copper ferricyanide lattice.

Example 2

Mix zinc powder, electronic conductive agent graphite powder and binder polyvinylidene fluoride in a mass ratio of 18:1:1, coat it on the carbon current collector, cut it into a certain size, and dry it in an oven. Zinc electrode. The copper ferricyanide electrode prepared in Example 1 is used as the positive electrode, the zinc electrode is used as the negative electrode, and the electrolyte solution is 1mol L ⁻¹ ZnSO ₄ aqueous solution to assemble a rechargeable zinc-ion battery in soft packaging.

The first charge and discharge curve of the prepared zinc ion battery at a constant current of 200 mAg ^-1 is shown in Figure 2 (calculated based on the mass of the positive electrode active material). As shown in the figure, a voltage appears between 2.0 and 2.2V. The charging platform has an obvious discharge platform at around 0.75V, and the Coulomb efficiency is 81%. The charge-discharge cycle curve of the prepared zinc-ion battery at a constant current of 200 mAg ^-1 (calculated by the mass of the positive electrode active material) is shown in Figure 3. It can be seen from the figure that the prepared zinc-ion battery has good cycle characteristics. If the structure is optimized, the battery charge and discharge characteristics and cycle stability will be significantly improved.

Example 3

Mix zinc powder, conductive agent graphite powder, binder polyvinylidene fluoride, and corrosion inhibitor copper powder in a mass ratio of 83:8:8:1, coat them on the carbon collector, and dry them in an oven. Cut it into a certain size to make a zinc electrode. The copper ferricyanide electrode prepared in Example 1 is used as the positive electrode, the zinc electrode is used as the negative electrode, and the electrolyte solution is 1mol L ⁻¹ ZnSO ₄ aqueous solution to assemble a rechargeable zinc-ion battery in soft packaging. The charge-discharge curve (calculated by the mass of the positive electrode active material) of the prepared zinc-ion battery at a constant current of 150mA g ^-1 is shown in Figure 4. As shown in the figure, a charging platform appears between the voltage range of 2.1~2.2V. There is an obvious discharge plateau at around 0.75V, and the Coulombic efficiency is 78%. If the structure is optimized, the battery charge and discharge characteristics and cycle stability will be significantly improved.

Claims (7)

1. An aqueous electrolyte rechargeable zinc ion battery, this battery is made up of positive pole, negative pole, diaphragm material between the former two and electrolyte; Wherein positive pole comprises the positive electrode active material on current collector and current collector, negative pole Including the current collector and the negative active material on the current collector, it is characterized in that the positive active material is a film material made of KMFe (CN) ₆ powder, electronic conductive agent and binder; the negative active material is zinc powder, corrosion inhibitor The film-like material that is made of agent, electron conduction agent and binding agent; Electrolytic solution is the liquid state with ion conductivity that takes the soluble salt of zinc as solute, water as solvent, and its pH value is 4～7; The KMFe ( CN) M in ₆ is Cu or Ni element. 2. The electrolyte rechargeable zinc-ion battery according to claim 1, characterized in that, in the positive electrode active material, the addition amount of the electron conducting agent and the binding agent is respectively less than 10% of the positive electrode active material mass. 3. electrolyte rechargeable zinc-ion battery according to claim 1, is characterized in that, the addition of corrosion inhibitor in the negative electrode active material is below 1% of the negative electrode active material quality, the addition of electronic conductive agent, binding agent The amounts are respectively less than 10% of the mass of the negative electrode active material. 4. The electrolyte rechargeable zinc-ion battery according to claim 1, characterized in that the electronic conductive agent is graphite, carbon black, carbon nanofibers or carbon nanotubes. 5. The electrolytic solution rechargeable zinc-ion battery according to claim 1, wherein the corrosion inhibitor is an oxide of indium or a hydroxide of indium or copper. 6. The electrolyte rechargeable zinc-ion battery according to claim 1, wherein the binding agent is polytetrafluoroethylene, polyvinylidene fluoride or cellulose. 7. The electrolyte rechargeable zinc-ion battery according to claim 1, wherein the soluble salt of zinc is zinc nitrate, zinc sulfate or zinc chloride.