Alkaline zinc-manganese flow battery and manufacturing method thereof

Abstract

The invention belongs to the technical field of batteries, and particularly relates to an alkaline zinc-manganese flow battery and a manufacturing method thereof.The alkaline zinc-manganese flow battery comprises a battery module, an electrolyte storage tank, a circulating pump, a circulating pipe and a battery control system; the positive electrode electrolyte is a potassium manganate alkaline solution, the negative electrode electrolyte is a zinc oxide alkaline solution, and the alkaline zinc-manganese flow battery has the characteristics of large capacity, long cycle charge and discharge life, high charge and discharge efficiency, good stability, high safety, easiness in later maintenance and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of batteries, and in particular relates to an alkaline zinc-manganese liquid flow battery and a manufacturing method thereof. Background Art

[0002] Developing energy storage and conversion devices with high energy density, long cycle life, low cost and high safety is crucial to fully utilize intermittent renewable energy such as solar energy, wind energy and hydropower.

[0003] Lithium-ion batteries are currently the main power source for portable electronics and electric vehicles due to their good energy density and durability. However, limited lithium resources, high manufacturing costs, and safety issues caused by toxic and flammable organic solvents used in lithium batteries (which make them difficult to recycle) are some of the obstacles to lithium batteries as clean energy infrastructure. In contrast, redox flow batteries have recently become one of the most promising next-generation energy storage technologies because they have many attractive properties, including energy / power capacity decoupling (i.e., energy is stored in electroactive substances dissolved in the electrolyte, while the output power depends on the number and size of electrodes in the battery stack), ultra-long cycle life, ultra-low cost and good safety. The present invention discloses a new type of alkaline zinc-manganese flow battery. It has the advantages of good safety, low cost, high energy density, etc., greatly improves the utilization rate of renewable energy, and is in line with the concept of green development. Summary of the invention

[0004] The purpose of the present invention is to provide an alkaline zinc-manganese liquid flow battery and a method for manufacturing the same. In view of the problems mentioned in the background technology that secondary batteries such as lithium batteries have few resources, high manufacturing costs, and are prone to environmental pollution, the present invention provides a zinc-manganese liquid flow battery and a method for manufacturing the same. The flow battery has low cost, relatively high energy utilization, abundant raw material resources, high safety, and meets the requirements of large-scale energy storage for batteries.

[0005] In order to achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0006] An alkaline zinc-manganese liquid flow battery, comprising a battery module, an electrolyte storage tank, a circulation pump, a circulation pipe and a battery control system;

[0007] The battery module is composed of a sealing rubber gasket, an exchange membrane, a graphite carbon felt, and an electrode plate. There are two electrode plates and a groove is provided on the side facing the electrolyte. The groove is used to place the graphite carbon felt and the sealing rubber gasket. The graphite carbon felt fits the inner wall of the groove. The exchange membrane is arranged between the two sealing rubber gaskets and there is a gap between the graphite carbon felt and the sealing rubber gasket. The two electrode plates are fixed to each other by stainless steel clamps and screws to form a battery module.

[0008] There are two electrolyte storage tanks, which store positive electrode electrolyte and negative electrode electrolyte respectively. The positive electrode electrolyte and negative electrode electrolyte in the two electrolyte storage tanks are connected to the two circulation pump fluid paths through circulation pipes respectively. The two circulation pumps are connected to the grooves on the electrode plate sides corresponding to the battery module through circulation pipes respectively. The corresponding grooves of the electrode plates are connected to the corresponding electrolyte storage tank fluid paths through circulation pipes.

[0009] The electrode plate is made of graphite, the size of the graphite carbon felt is 2cm*2cm, and the exchange membrane is a perfluorosulfonic acid membrane.

[0010] The exchange membrane needs to be cut into a size of 3 cm*3 cm before use and soaked in 1 mol L -1 NaOH, heated in a water bath at 80 °C for 3 h, removed and immersed in 1 mol L -1 of NaOH for later use.

[0011] A method for manufacturing an alkaline zinc-manganese liquid flow battery is used to manufacture an alkaline zinc-manganese liquid flow battery, wherein the specific steps of manufacturing the electrolyte are as follows:

[0012] Step 1: dissolving ZnO powder in NaOH solution to obtain a negative electrode electrolyte;

[0013] Step 2: Dissolve K2MnO4 powder in NaOH solution to obtain a positive electrode electrolyte.

[0014] In step 1, the concentration of ZnO is 0.1 mol L -1 , NaOH concentration is 6 mol L -1 .

[0015] In step 2, the concentration of K2MnO4 is 0.1 mol L -1 , the concentration of NaOH is 6 mol L -1 .

[0016] Compared with the prior art, the present invention has at least the following advantages:

[0017] (1) Zinc and manganese are both metal elements with relatively abundant resources and relatively low raw material costs. Using potassium manganate and zinc oxide as positive and negative active materials gives liquid flow batteries certain advantages in cost and resources. The raw material resources are abundant and suitable for large-scale mass production.

[0018] (2) The zinc-manganese liquid flow battery of the present invention has high charge and discharge efficiency, long battery life, and stable charge and discharge.

[0019] (3) The zinc-manganese liquid flow battery of the present invention has high safety and is easy to maintain in the later stage. Its performance meets the requirements of large-scale energy storage of batteries and has certain commercial prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is further illustrated by means of the non-limiting examples given in the accompanying drawings.

[0021] Figure 1 The diagram is a reaction mechanism diagram of the alkaline zinc-manganese liquid flow battery prepared in Example 1-3.

[0022] Figure 2 This is a photo of the alkaline zinc-manganese liquid flow battery prepared in Example 1-3.

[0023] Figure 3 It is a schematic diagram of the structure of the present invention.

[0024] Figure 4 It is a schematic diagram of the structure of the present invention.

[0025] Figure 5 This is the charging time curve of the first cycle of the alkaline zinc-manganese liquid flow battery prepared in Example 1.

[0026] Figure 6 This is the discharge time curve of the first cycle of the alkaline zinc-manganese liquid flow battery prepared in Example 1.

[0027] Figure 7 The discharge capacity change and capacity retention rate curve of the alkaline zinc-manganese liquid flow battery prepared in Example 1 after 120 cycles.

[0028] Figure 8 This is the charge and discharge time curve of the first cycle of the alkaline zinc-manganese liquid flow battery prepared in Example 2.

[0029] Fig. 9 The coulombic efficiency change curve of the alkaline zinc-manganese liquid flow battery prepared in Example 2 after 200 cycles.

[0030] Fig.10 The voltage variation curve of the alkaline zinc-manganese liquid flow battery prepared in Example 3 during the first three cycles.

[0031] Fig.11 The energy efficiency change curve of the alkaline zinc-manganese liquid flow battery prepared in Example 3 after 200 cycles.

[0032] Sealing rubber gasket 1, exchange membrane 2, electrode plate 3, groove 31. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0034] like Figure 1-4 As shown, an alkaline zinc-manganese liquid flow battery includes a battery module, an electrolyte storage tank, a circulation pump, a circulation pipe and a battery control system;

[0035] The battery module is composed of a sealing rubber gasket, an exchange membrane, a graphite carbon felt, and an electrode plate. There are two electrode plates and a groove is provided on the side facing the electrolyte. The groove is used to place the graphite carbon felt and the sealing rubber gasket. The graphite carbon felt fits the inner wall of the groove. The exchange membrane is arranged between the two sealing rubber gaskets and there is a gap between the graphite carbon felt and the sealing rubber gasket. The two electrode plates are fixed to each other by stainless steel clamps and screws to form a battery module.

[0036] There are two electrolyte storage tanks, which store positive electrode electrolyte and negative electrode electrolyte respectively. The positive electrode electrolyte and negative electrode electrolyte in the two electrolyte storage tanks are connected to the two circulation pump fluid paths through circulation pipes respectively. The two circulation pumps are connected to the grooves on the electrode plate sides corresponding to the battery module through circulation pipes respectively. The corresponding grooves of the electrode plates are connected to the corresponding electrolyte storage tank fluid paths through circulation pipes.

[0037] The electrode plate is made of graphite, the size of the graphite carbon felt is 2cm*2cm, and the exchange membrane is a perfluorosulfonic acid membrane.

[0038] The exchange membrane needs to be cut into a size of 3 cm*3 cm before use and soaked in 1 mol L -1 NaOH, heated in a water bath at 80 °C for 3 h, removed and immersed in 1 mol L -1 of NaOH for later use.

[0039] Example 1: (1) Preparation of electrolyte

[0040] Dissolve ZnO powder in NaOH solution to obtain negative electrode electrolyte. The concentration of ZnO is 0.1 mol L -1 , NaOH concentration is 6 mol L -1 .

[0041] Dissolve K2MnO4 powder in NaOH solution to obtain positive electrode electrolyte. The concentration of K2MnO4 is 0.1 mol L -1 , the concentration of NaOH is 6 mol L -1 .

[0042] (2) Treatment of battery separators

[0043] Cut a 3 cm × 3 cm perfluorosulfonic acid membrane and soak it in 1 mol L -1 NaOH, heated in a water bath at 80 °C for 3 h, removed and immersed in 1 mol L -1 of NaOH for later use.

[0044] (3) Alkaline zinc-manganese flow battery, including battery module, electrolyte storage tank (20mL), circulation pump, circulation pipe and battery control system (blue battery test system);

[0045] The battery module is composed of a sealing rubber gasket, an exchange membrane, a graphite carbon felt, and an electrode plate. There are two electrode plates and a groove is provided on the side facing the electrolyte. The groove is used to place the graphite carbon felt and the sealing rubber gasket. The graphite carbon felt fits the inner wall of the groove. The exchange membrane is arranged between the two sealing rubber gaskets and there is a gap between the graphite carbon felt and the sealing rubber gasket. The two electrode plates are fixed to each other by stainless steel clamps and screws to form a battery module.

[0046] There are two electrolyte storage tanks, which store positive electrode electrolyte and negative electrode electrolyte respectively. The positive electrode electrolyte and negative electrode electrolyte in the two electrolyte storage tanks are connected to the two circulation pump fluid paths through circulation pipes respectively. The two circulation pumps are connected to the grooves on the electrode plate sides corresponding to the battery module through circulation pipes respectively. The corresponding grooves of the electrode plates are connected to the corresponding electrolyte storage tank fluid paths through circulation pipes.

[0047] The positive electrode electrolyte and the negative electrode electrolyte obtained in step (1) are respectively injected into two liquid storage tanks and injected into the positive electrode and negative electrode sides respectively to form a zinc-manganese liquid flow battery. The circulation of the electrolyte is achieved through the circulation pump and its pipeline connection, and the battery is charged and discharged through the control system. The exchange membrane in this embodiment is the perfluorosulfonic acid membrane obtained by the treatment in step (2).

[0048] (4) Charging performance test of zinc-manganese flow battery

[0049] The constant current charging method was used to test the charge-time curve of the flow battery in this embodiment under the condition of 60 mA constant current charging, and the voltage change was recorded. When the charging voltage was 2.1 V, it was switched to constant current discharge. The charging test results are shown in Figure 2. Figure 5 As shown, the charging capacity is 44.1mAh.

[0050] (5) Discharge performance test of zinc-manganese flow battery

[0051] The discharge-time curve of the flow battery in this embodiment was tested under the condition of 60 mA constant current discharge by constant current discharge method, and the voltage change was recorded. When the discharge voltage was 1.5 V, constant current charging was switched. The charging test results are shown in Figure 2. Figure 6 As shown, the discharge capacity is 38.3 mAh.

[0052] (6) Zinc-manganese flow battery charge and discharge life test

[0053] The flow battery of this embodiment was tested at a constant current of 60 mA using a constant current charge and discharge method. After 120 cycles, the capacity retention rate of the battery was calculated to be more than 90%. The results are as follows: Figure 7 shown.

[0054] Example 2: Based on the zinc-manganese liquid flow battery prepared in Example 1, the constant current of this example is 80 mA, specifically:

[0055] (1) Charging performance test of zinc-manganese flow battery

[0056] The constant current charging method was used to test the charge-time curve of the flow battery in this embodiment under the condition of 80 mA constant current charging, and the voltage change was recorded. When the charging voltage was 2.1 V, it was switched to constant current discharge. The charging test results are shown in Figure 2. Figure 8 As shown, the charging capacity is 47.7mAh.

[0057] (2) Discharge performance test of zinc-manganese flow battery

[0058] The discharge-time curve of the flow battery in this embodiment was tested under the condition of 80 mA constant current discharge by constant current discharge method, and the voltage change was recorded. When the discharge voltage was 1.5 V, constant current charging was switched. The charging test results are shown in Figure 2. Figure 8 As shown, the discharge capacity is 39.7 mAh.

[0059] (3) Coulombic efficiency test of zinc-manganese liquid flow battery

[0060] The flow battery of this embodiment was tested at a constant current of 80 mA using a constant current charge and discharge method. After 200 cycles, the coulombic efficiency of the battery was calculated to be stable at about 90%. Fig. 9 shown.

[0061] Example 3: Based on the zinc-manganese liquid flow battery prepared in Example 1, the constant current of this example is 100 mA, specifically:

[0062] (1) Charging performance test of zinc-manganese flow battery

[0063] The constant current charging method was used to test the charge-time curve of the flow battery in this embodiment under the condition of 100 mA constant current charging, and the voltage change was recorded. When the charging voltage was 2.1 V, it was switched to constant current discharge. The charging test results are shown in Figure 2. Fig.10 As shown, the charging capacity is 45.2mAh.

[0064] (2) Discharge performance test of zinc-manganese flow battery

[0065] The discharge-time curve of the flow battery of this embodiment was tested under the condition of 100 mA constant current discharge by constant current discharge method, and the voltage change was recorded. When the discharge voltage was 1.5 V, constant current charging was switched. The discharge test results are shown in Figure 2. Fig.10 As shown, the discharge capacity is 39.5 mAh.

[0066] (3) Energy efficiency test of zinc-manganese flow battery

[0067] The flow battery of this embodiment was tested at a constant current of 100 mA using a constant current charge and discharge method. After 200 cycles, the energy efficiency of the battery was calculated to be more than 80%. The results are as follows: Fig.11 shown.

[0068] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. An alkaline zinc-manganese liquid flow battery, characterized in that: It consists of a battery module, an electrolyte storage tank, a circulation pump, a circulation pipe and a battery control system; The battery module is composed of a sealing rubber gasket, an exchange membrane, a graphite carbon felt, and an electrode plate. There are two electrode plates and a groove is provided on the side facing the electrolyte. The groove is used to place the graphite carbon felt and the sealing rubber gasket. The graphite carbon felt fits the inner wall of the groove. The exchange membrane is arranged between the two sealing rubber gaskets and there is a gap between the graphite carbon felt and the sealing rubber gasket. The two electrode plates are fixed to each other by stainless steel clamps and screws to form a battery module. There are two electrolyte storage tanks, which store positive electrode electrolyte and negative electrode electrolyte respectively. The positive electrode electrolyte and negative electrode electrolyte in the two electrolyte storage tanks are connected to the two circulation pump fluid paths through circulation pipes respectively. The two circulation pumps are connected to the grooves on the electrode plate sides corresponding to the battery module through circulation pipes respectively. The corresponding grooves of the electrode plates are connected to the corresponding electrolyte storage tank fluid paths through circulation pipes.

2. An alkaline zinc-manganese liquid flow battery according to claim 1, characterized in that: The electrode plate is made of graphite, the size of the graphite carbon felt is 2cm*2cm, and the exchange membrane is a perfluorosulfonic acid membrane.

3. An alkaline zinc-manganese liquid flow battery according to claim 2, characterized in that: The exchange membrane needs to be cut into a size of 3 cm*3 cm before use and soaked in 1 mol L -1 NaOH, heated in a water bath at 80 °C for 3 h, removed and immersed in 1 mol L -1 of NaOH for later use.

4. A method for manufacturing an alkaline zinc-manganese liquid flow battery, characterized in that: Used to manufacture the alkaline zinc-manganese liquid flow battery according to claim 1, wherein the specific steps of manufacturing the electrolyte are as follows: Step 1: dissolving ZnO powder in NaOH solution to obtain a negative electrode electrolyte; Step 2: Dissolve K2MnO4 powder in NaOH solution to obtain a positive electrode electrolyte.

5. The method for manufacturing an alkaline zinc-manganese flow battery according to claim 4, characterized in that: In step 1, the concentration of ZnO is 0.1 mol L -1 , NaOH concentration is 6 mol L -1 .

6. The method for manufacturing an alkaline zinc-manganese flow battery according to claim 5, characterized in that: In step 2, the concentration of K2MnO4 is 0.1 mol L -1 , the concentration of NaOH is 6 mol L -1 .

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