WO2021017345A1

WO2021017345A1 - Method for preventing zinc deposition of zinc ion flow battery, and zinc ion flow battery

Info

Publication number: WO2021017345A1
Application number: PCT/CN2019/121141
Authority: WO
Inventors: 陈忠伟; 张益宁; 侯腾腾; 朱明华
Original assignee: 苏州沃泰丰能电池科技有限公司
Priority date: 2019-07-30
Filing date: 2019-11-27
Publication date: 2021-02-04
Also published as: CN110459791A

Abstract

Disclosed are a method for preventing the zinc deposition of a zinc ion flow battery, and a zinc ion flow battery. The zinc ion flow battery comprises a positive electrode and a negative electrode, wherein a porous sponge is attached to a surface of the negative electrode, and the porous sponge is attached to a side, near the positive electrode, of the negative electrode. Since the porous sponge is attached to the side, near the positive electrode, of the negative electrode, zinc generated by the negative electrode in a zinc deposition process is supported by the porous sponge, such that the zinc will not fall to the bottom if same falls. If the zinc falls off and becomes non-conductive zinc particles, the zinc particles are trapped inside the porous sponge, and the zinc particles are turned on during continued deposition when charging is performed the next time, such that the zinc particles are made to be live and continue to discharge.

Description

Method for preventing zinc deposition of zinc ion flow battery and zinc ion flow battery

Technical field

The invention relates to the field of zinc ion batteries, in particular to a method for preventing zinc deposition in a zinc ion flow battery and a zinc ion flow battery.

Background technique

Flow battery is an electrochemical energy storage technology proposed by Thaller (NASA Lewis Research Center, Cleveland, United States) in 1974. The flow energy storage battery system is composed of a stack unit, an electrolyte solution and an electrolyte solution storage and supply unit, and a control management unit. The core of the flow battery system is composed of a stack and (a stack is composed of dozens of sections for oxidation-reduction reactions) and a single cell for charging and discharging processes in series according to specific requirements. The structure is similar to a fuel cell stack.

Flow battery is a new type of storage battery. Flow battery is a high-performance storage battery that uses positive and negative electrolytes to separate and circulates separately. It has the characteristics of high capacity, wide use field (environment), and long cycle life. Of a new energy product. Redox flow battery is a new type of large-capacity electrochemical energy storage device that is being actively developed. It is different from batteries that usually use solid material electrodes or gas electrodes. Its active material is a flowing electrolyte solution. Its most significant feature is Large-scale storage of electricity, in the context of widespread use of renewable energy, it can be foreseen that flow batteries will usher in a period of rapid development.

Chinese patent document CN102544563A discloses a zinc deposition type flow energy storage battery system and its operation mode. It includes a storage tank containing positive and negative electrolytes and a battery. The storage tank of the positive electrolyte is connected to the positive electrode of the battery through a pipeline. The material inlet and outlet are connected separately, and a liquid pump is installed on the battery anode material inlet pipeline; the negative electrolyte storage tank is connected to the battery anode material inlet and outlet through the pipeline, and a liquid pump is installed on the battery anode material inlet pipeline; There are two storage tanks for the negative electrolyte solution, or one storage tank with two independent storage spaces. The two storage tanks or the two independent storage spaces of the storage tank respectively pass through the pipeline and the battery negative electrode material inlet and The outlets are connected separately; that is, the pipelines between the two liquid storage tanks or the two independent storage spaces of the liquid storage tank between the battery negative electrode material inlet and the outlet are connected in parallel, and are connected to the two liquid storage tanks or two independent storage tanks. The storage space is respectively filled with charged electrolyte and discharged electrolyte.

The battery system disclosed in the above patent documents improves the zinc negative electrode side to increase the battery voltage efficiency and energy density; however, it does not propose an effective solution for preventing zinc deposition, so it is necessary to propose a new method for preventing zinc deposition. Program.

Summary of the invention

The technical problem to be solved by the present invention is to provide a method for preventing zinc deposition in a zinc ion flow battery.

In order to solve the above technical problems, the present invention adopts a technical solution: a method for preventing zinc deposition in a zinc ion flow battery. The zinc ion flow battery includes a positive electrode and a negative electrode. A porous sponge is attached to the surface of the negative electrode. The porous sponge is attached to the side of the negative electrode close to the positive electrode.

The charging and discharging process of zinc ion flow battery is a process of mutual transformation of zinc and zinc oxide. During the charging process, the zinc ions become zinc solids and deposit on the surface of the negative electrode. During the discharge process, the zinc solids become zinc ions and dissolve on the surface of the electrolyte. The whole process is designed to transform between solid and liquid. During this transformation process, there will be problems of not dense and uneven zinc deposition. Then, if the surface is not tight enough, zinc will fall off and precipitate in the electrolyte. Then it deposits on the bottom of the battery, causing a loss of capacity and a short circuit between the positive and negative electrodes.

By adopting the above technical solution of the present invention, the porous sponge is attached to the side of the negative electrode close to the positive electrode, and the zinc generated during the zinc deposition process of the negative electrode is supported by the porous sponge, and will not fall to the bottom if it falls. If it falls off and becomes non-conductive zinc particles and is trapped in the porous sponge, it will be turned on during the next charging process (this is because the deposited metal will fall off and become invalid capacity. When recharging, the new The zinc will grow up and will directly contact the zinc surface that fell off last time, so that the original ineffective zinc particles can be turned on during the discharge, so that it becomes active and continues to discharge.

Preferably, the porous sponge is attached to the surface of the negative electrode by pressing on four sides with a pressing plate; in this way, the porous sponge is closely attached to the negative electrode.

Preferably, the porous sponge is a foam material made of polypropylene, polylactic acid, polyurethane or EPDM rubber.

Preferably, the zinc ion flow battery has the following components from left to right: metal end plate, plastic end plate, gasket one, negative electrode deflector one, gasket two, negative electrode, gasket three, porous sponge, negative electrode Flow deflector two, gasket four, gasket five, diaphragm, gasket six, positive splint, gasket seven, gasket eight, positive electrode, gasket nine, positive splint, gasket ten, positive diversion groove, gasket 11. Plastic partitions and metal partitions;

Through the holes arranged around the above-mentioned components, the screw is used to apply pressure to tightly seal, the electrolyte enters from one end, and flows out from the other end after passing through all the cavities.

The technical problem to be solved by the present invention Another technical problem is to provide a zinc ion flow battery.

In order to solve the above technical problems, the technical solution adopted by the present invention is that the zinc ion flow battery includes at least a positive electrode and a negative electrode, and a porous sponge is attached to the surface of the negative electrode between the positive electrode and the negative electrode. The porous sponge is attached to the side of the negative electrode close to the positive electrode.

As mentioned above, the porous sponge is attached to the side of the negative electrode close to the positive electrode. The zinc produced during the zinc deposition process of the negative electrode is supported by the porous sponge and will not fall to the bottom if it falls. If it falls off and becomes non-conductive zinc particles and is trapped in the porous sponge, it will be turned on during the next charging process (this is because the deposited metal will fall off and become invalid capacity. When recharging, the new The zinc will grow up and will directly contact the zinc surface that fell off last time, so that the original ineffective zinc particles can be turned on during the discharge, so that it becomes active and continues to discharge.

Research and testing show that the zinc ion flow battery with porous sponge as a filter can double the cycle times to 3000-5000 cycles, and the porous sponge as a filter has little effect on the energy efficiency of the battery, which can improve the battery Cycle performance; after the battery is disassembled, it can be seen that there is no obvious zinc deposition on the bottom of the negative electrode battery from the charging electrode. The porous sponge can be used as a filter to prevent zinc from depositing to the bottom; the porous sponge can be used as a filter to significantly improve the large amount of zinc deposition Phenomenon, reducing the probability of zinc contact with the positive electrode.

Preferably, a separator is arranged between the porous sponge and the positive electrode.

Preferably, the porous sponge is attached to the surface of the negative electrode by pressing a plate on four sides.

Preferably, the pore size of the porous sponge is 30 PPI and the thickness is 5 mm.

Preferably, from left to right, the zinc ion flow battery is: positive electrode one, separator one, porous sponge one, negative electrode, porous sponge two, separator two and positive electrode two.

Preferably, from left to right, the zinc ion flow battery is: metal end plate, plastic end plate, gasket one, negative electrode deflector one, gasket two, negative electrode, gasket three, porous sponge, negative electrode conductor Flow plate two, gasket four, gasket five, diaphragm, gasket six, positive splint, gasket seven, gasket eight, positive electrode, gasket nine, positive splint, gasket ten, positive diversion groove, gasket ten 1. Plastic partition and metal partition.

The technical scheme of the present invention can be mainly used in the field of zinc-ion batteries (batteries and flow batteries), including zinc-air batteries, zinc-iodine batteries, zinc-nickel batteries, zinc-iron batteries and other batteries that use zinc as the negative electrode material.

Description of the drawings

The following is a further detailed description in conjunction with the drawings and the embodiments of the present invention:

Fig. 1 is a simplified schematic diagram of the first battery structure obtained by the method for preventing zinc deposition in a zinc ion flow battery of the present invention;

2 is a simplified schematic diagram of the second battery structure obtained by the method for preventing zinc deposition in the zinc ion flow battery of the present invention;

3 is a schematic diagram of the structure of the zinc ion flow battery of the present invention;

4 is an effect diagram of the zinc ion flow battery obtained in Example 3 and the existing battery without a filter after use;

Among them: 1-positive electrode; 2-negative electrode; 3-porous sponge; 4-diaphragm; 5-positive electrode one; 6-diaphragm one; 7-porous sponge one; 8-porous sponge two; 9-diaphragm two; 10-positive electrode two 11-metal end plate; 12-plastic end plate; 13-seal one; 14-negative air deflector one; 15-seal two; 16-seal three; 17-negative air deflector two; 18-seal Pad four; 19-seal five; 20-seal six; 21-positive splint; 22-seal seven; 23-seal eight; 24 seal nine; 25-seal ten; 26-seal ten; 27 positive lead Launder; 28-seal eleven; 29-plastic partition; 30-metal partition.

Detailed ways

Example 1: The method for preventing zinc deposition in a zinc ion flow battery of the present invention. The zinc ion flow battery includes a positive electrode 1 and a negative electrode 2, and a porous sponge 3 is attached to the surface of the negative electrode 2. 3 is attached to the side of the negative electrode 2 close to the positive electrode 1, and the porous sponge 3 is attached to the surface of the negative electrode 2 by pressing on four sides with a press plate.

The porous sponge 3 is a foam material made of polypropylene, polylactic acid, polyurethane or EPDM rubber.

The obtained zinc ion flow battery is shown in Fig. 1, the porous sponge 3 has a pore size of 30 PPI and a thickness of 5 mm.

Example 2: Different from Example 1, the zinc ion flow battery obtained from left to right is: positive electrode one 5, separator one 6, porous sponge one 7, negative electrode 2, porous sponge two 8, and separator two 9. And positive electrode two 10, as shown in Figure 2.

Example 3: The method for preventing zinc deposition in a zinc ion flow battery of the present invention. The zinc ion flow battery includes a positive electrode 1 and a negative electrode 2, and a porous sponge 3 is attached to the surface of the negative electrode 2. 3 is attached to the side of the negative electrode 2 close to the positive electrode 1, the porous sponge 3 is attached to the surface of the negative electrode 2 by pressing on four sides with a pressing plate; between the porous sponge 3 and the positive electrode 1 A diaphragm 4 is provided.

The obtained zinc ion flow battery is shown in Figure 3, the porous sponge 3 has a pore size of 30PPI and a thickness of 5mm; the zinc ion flow battery obtained in this example has the following components from left to right: metal end plate 11, plastic End plate 12, gasket one 13, negative electrode deflector one 14, gasket two 15, negative electrode 2, gasket three 16, porous sponge 3, negative electrode deflector two 17, gasket four 18, gasket five 19, Separator 4, gasket six 20, positive splint 21, gasket seven 22, gasket eight 23, positive electrode 1, gasket nine 24, positive splint 25, gasket ten 26, positive diversion groove 27, gasket eleven 28 , Plastic partition 29 and metal partition 30.

As shown in Figure 4, it is the effect diagram of the battery of this embodiment after use. It can be clearly seen from the figure that the battery without the porous sponge as a filter screen has a large amount of zinc deposition; and the porous sponge is added as a filter. The filter does not.

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the foregoing embodiments. The foregoing embodiments and descriptions only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and improvements, such as larger or smaller sizes, or changes in materials, all fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

A method for preventing zinc deposition in a zinc ion flow battery, the zinc ion flow battery comprising a positive electrode and a negative electrode, characterized in that a porous sponge is attached to the surface of the negative electrode, and the porous sponge is attached to the The side of the negative electrode near the positive electrode.
The method for preventing zinc deposition in a zinc ion flow battery according to claim 1, wherein the porous sponge is adhered to the surface of the negative electrode by pressing a plate on all sides.
The method for preventing zinc deposition in a zinc ion flow battery according to claim 1, wherein the porous sponge is a foam material made of polypropylene, polylactic acid, polyurethane or EPDM.
The method for preventing zinc deposition in a zinc ion flow battery according to any one of claims 1 to 3, wherein the zinc ion flow battery has the following components from left to right: metal end plates, plastic end plates, Seal one, negative pole deflector one, seal two, negative pole, seal three, porous sponge, negative pole deflector two, seal four, seal five, diaphragm, seal six, positive splint, seal seven, Sealing gasket eight, positive electrode, sealing gasket nine, positive splint, sealing gasket ten, positive electrode diversion groove, sealing gasket 11, plastic separator and metal separator;

Through the holes arranged around the above-mentioned components, the screw is used to apply pressure to tightly seal, the electrolyte enters from one end, and flows out from the other end after passing through all the cavities.
A zinc ion flow battery, comprising at least a positive electrode and a negative electrode, characterized in that a porous sponge is attached to the surface of the negative electrode between the positive electrode and the negative electrode, and the porous sponge is attached to the The side of the negative electrode close to the positive electrode.
The zinc ion flow battery according to claim 5, wherein a separator is provided between the porous sponge and the positive electrode.
The zinc ion flow battery according to claim 6, wherein the porous sponge is attached to the surface of the negative electrode by pressing on four sides with a pressing plate.
The zinc ion flow battery according to claim 7, wherein the porous sponge has a pore size of 30 PPI and a thickness of 5 mm.
The zinc ion flow battery according to claim 8, wherein the zinc ion flow battery is in order from left to right: positive electrode one, separator one, porous sponge one, negative electrode, porous sponge two, separator two and Positive two.
The zinc ion flow battery according to claim 8, wherein the zinc ion flow battery is, from left to right, respectively: metal end plate, plastic end plate, sealing gasket one, negative flow deflector one, sealing Pad two, negative electrode, gasket three, porous sponge, negative electrode deflector two, gasket four, gasket five, diaphragm, gasket six, positive splint, gasket seven, gasket eight, positive electrode, gasket nine, positive electrode Plywood, gasket ten, positive diversion groove, gasket eleven, plastic separator and metal separator.