Experimental device of total iron flow battery

Abstract

An experimental device of an all-iron flow battery relates to the technical field of flow batteries, and is characterized by comprising a flow battery pack, a blue electric battery test device connected with the flow battery pack, liquid storage tanks symmetrically arranged on the positive and negative sides of the flow battery pack, and an electrolyte inlet pipe and an electrolyte return pipe which are connected with the flow battery pack and the liquid storage tanks, the pump is arranged on the electrolyte inlet pipe; a magnetic stirrer is arranged at the bottom of the liquid storage tank on one side of the negative electrode, and a magnetic stirring rod corresponding to the magnetic stirrer is arranged in the liquid storage tank; a nitrogen inlet pipe and a nitrogen outlet pipe are arranged on the liquid storage tank; the nitrogen inlet pipe is connected with a nitrogen cylinder; the flow battery pack comprises an ion exchange membrane, and electrode frames, bipolar plates and battery end plates which are symmetrically arranged on two sides of the ion exchange membrane in sequence; an electrode is provided inside the electrode frame. According to the utility model, magnetic stirring and nitrogen oxygen isolation measures are adopted, so that the discharge capacity of the all-iron flow battery is remarkably improved.

Description

Technical Field

[0001] This utility model relates to the field of flow battery technology, and in particular to an experimental apparatus for an all-iron flow battery. Background Technology

[0002] The all-iron liquid flow battery (ABL) is a novel renewable energy storage technology that utilizes the redox process of iron ions in an electrolyte solution to store and release electrical energy. This battery technology has enormous potential in the energy storage field due to its low cost and abundant resources, and can provide effective support for the large-scale application of renewable energy. With the increasing global demand for clean energy, the research and application of ABL experimental devices are receiving widespread attention.

[0003] However, current experimental setups for all-ferrous flow batteries still face several challenges. In particular, Fe²⁺ (ferrous ions) has strong reducing properties and is easily oxidized upon contact with air, affecting the content of active materials in the electrolyte. Furthermore, during negative electrode charging, the conversion of Fe²⁺ to Fe easily leads to the deposition of elemental iron, which can clog fiber pores, thus impacting the battery's charging and discharging process and overall efficiency. Utility Model Content

[0004] To overcome the above deficiencies, this invention provides an experimental apparatus for an all-iron flow battery, which can effectively prevent the oxidation of Fe2+ and ensure that elemental iron is uniformly deposited on the electrode surface, avoiding clogging of fiber pores, thereby improving the charge and discharge performance of the battery.

[0005] This utility model is achieved through the following technical solution: an experimental device for an all-iron flow battery, comprising a flow battery pack, a storage tank symmetrically arranged on both sides of the positive and negative electrodes of the flow battery pack, an electrolyte inlet pipe and an electrolyte return pipe connecting the flow battery pack and the storage tank, and a pump arranged on the electrolyte inlet pipe. The device is characterized by: a magnetic stirrer being provided at the bottom of the storage tank, and a magnetic stirring rod corresponding to the magnetic stirrer being provided inside the storage tank; a nitrogen inlet pipe and a nitrogen outlet pipe being provided on the storage tank; the nitrogen inlet pipe being connected to a nitrogen cylinder; the flow battery pack comprising an ion exchange membrane, and electrode frames, bipolar plates, and battery end plates symmetrically arranged on both sides of the ion exchange membrane; electrodes being arranged inside the electrode frames.

[0006] Furthermore, the bipolar plate, electrode frame, and ion exchange membrane are tightly connected, forming a cavity inside the electrode frame for storing the electrolyte.

[0007] Furthermore, the battery end plate and electrode frame are provided with holes for the electrolyte inlet pipe and electrolyte return pipe to pass through, and the electrolyte inlet pipe and electrolyte return pipe are connected to the cavity where the electrolyte is stored.

[0008] Compared with the prior art, the beneficial effects and features of this utility model are as follows:

[0009] To prevent Fe2+ oxidation: Nitrogen gas is continuously introduced into the positive and negative electrode reservoirs via a nitrogen cylinder, effectively isolating them from air and significantly reducing the chance of ferrous ions (Fe2+) being oxidized. This helps maintain the content of active materials in the electrolyte and ensures stable battery performance.

[0010] Improved iron deposition: A magnetic stirrer is used to stir the electrolyte in the negative electrode storage tank, which allows iron to be deposited evenly on the electrode surface. This avoids the phenomenon of iron accumulating and clogging the electrode fiber pores during negative electrode charging, thereby reducing the risk of current interruption and improving the battery's charging and discharging efficiency. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0012] Figure 2 This is a schematic diagram of the usage state of this utility model;

[0013] Figure 3 This is a comparison chart of the voltage efficiency variation curves of this invention under different electrical densities.

[0014] Figure 4 This is a comparison graph of the energy efficiency variation curves of this utility model under different electrical densities.

[0015] The main components in the diagram are numbered as follows: 1. Magnetic stirrer; 2. Nitrogen cylinder; 3. Storage tank; 4. Battery end plate; 5. Bipolar plate; 6. Electrode frame; 7. Electrode; 8. Ion exchange membrane; 9. Pump; 10. Blue battery testing equipment; 11. Magnetic stirring rod; 13. Nitrogen inlet pipe; 12. Nitrogen outlet pipe; 14. Electrolyte inlet pipe; 15. Electrolyte return pipe.

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, and the other drawings obtained are all within the protection scope claimed by this utility model. Detailed Implementation

[0017] The following combination Figure 1-4The contents of this utility model will be described in detail through specific embodiments. Example

[0018] The experimental setup for the all-iron flow battery includes a flow battery pack, storage tanks 3 symmetrically arranged on both sides of the positive and negative electrodes of the flow battery pack, an electrolyte inlet pipe 14 and an electrolyte return pipe 15 connecting the flow battery pack and the storage tanks, and a pump 9 mounted on the electrolyte inlet pipe. A magnetic stirrer 1 is installed at the bottom of the storage tank, and a corresponding magnetic stirring rod 11 is installed inside the storage tank. A nitrogen inlet pipe 13 and a nitrogen outlet pipe 12 are installed on the storage tank. Nitrogen cylinder 2 is connected; the flow battery pack includes an ion exchange membrane 8, and electrode frames 6, bipolar plates 5, and battery end plates 4 are symmetrically arranged on both sides of the ion exchange membrane; an electrode 7 is arranged inside the electrode frame; the bipolar plates, electrode frames, and ion exchange membrane are tightly connected, so that the inside of the electrode frame forms a cavity for storing electrolyte; the battery end plate and electrode frames are provided with holes for electrolyte inlet pipes and electrolyte return pipes to pass through, and the electrolyte inlet pipes and electrolyte return pipes are connected to the cavity for storing electrolyte.

[0019] Chemicals and Equipment

[0020] Positive electrode electrolyte: 80 mL of 0.6 mol / L FeCl2 (ferrous chloride) and 2 mol / L KCl (potassium chloride) aqueous solution.

[0021] Negative electrode electrolyte: 80 mL of 0.3 mol / L FeCl2 (ferrous chloride) and 2 mol / L KCl (potassium chloride) aqueous solution.

[0022] Electrode material: Activated carbon felt is used as the electrode.

[0023] Ion exchange membrane: A cation exchange membrane is used to separate the positive and negative electrolytes.

[0024] Other components: Landian battery testing equipment: model CT3001K, specification 5V12A8CQ, manufactured by Wuhan Landian Electronics Co., Ltd.

[0025] Magnetic stirrer and magnetic stirring rod: Model Leici JB-3A thermostatic timer stirrer, manufactured by Shanghai Instrument & Electronics Scientific Instruments Co., Ltd.

[0026] Single-cell charge and discharge research operation steps:

[0027] The pump drives the positive and negative electrolytes to flow out from their respective storage tanks, pass through the electrodes, and return to their respective storage tanks, forming a closed loop.

[0028] During the electrolyte flow, a nitrogen atmosphere is maintained inside the storage tank to isolate it from air and prevent the oxidation of ferrous iron.

[0029] A magnetic stirrer, in conjunction with a magnetic stirring rod in the storage tank, stirs the electrolyte in the storage tank to ensure that the concentration of the electrolyte on the surface and in the bulk is consistent, thereby avoiding concentration polarization.

[0030] The Blue Battery Testing Equipment 10 is connected to the bipolar plate and is used to control the charging and discharging process of the battery.

[0031] The computer collects and records voltage, current, and other relevant data during the charging and discharging process using the Blue Battery testing equipment.

[0032] Experimental conditions:

[0033] The charging voltage and discharge termination voltage are fixed settings.

[0034] The voltage sampling frequency is 1 time / 30 seconds.

[0035] The control system automatically switches between charging and discharging states based on set conditions.

[0036] Each experiment used four different current densities, with each current density being cycled more than five times.

[0037] in conclusion

[0038] Unresolved situation:

[0039] In a battery without stirring and oxygen isolation, after several charge-discharge cycles, the iron deposition on the negative electrode side is uneven and often blocks the electrode fiber pores, causing current interruption and affecting the detection of relevant data of the electrode felt. At a current density of 40 mA / cm2, the voltage efficiency (VE) is 46.57% and the energy efficiency (EE) is 38.23%.

[0040] The effect after improvement:

[0041] After the improvements, the voltage efficiency (VE) is 65.54% and the energy efficiency (EE) is 67.73%, representing an increase of 40.73% and 77.16% respectively compared to the unimproved version. Therefore, both voltage efficiency and energy efficiency have been significantly improved, and the discharge capacity of the all-iron flow battery has also been significantly increased. This effectively solves the problems of excessively long charge and discharge times and incomplete reactions of active materials during battery testing, greatly improving testing efficiency.

Claims

1. An experimental apparatus for an all-ferrous flow battery, characterized in that: The device includes a flow battery pack, a blue battery testing device connected to the flow battery pack, a storage tank symmetrically arranged on both sides of the positive and negative electrodes of the flow battery pack, an electrolyte inlet pipe and an electrolyte return pipe connecting the flow battery pack and the storage tank, and a pump installed on the electrolyte inlet pipe; a magnetic stirrer is installed at the bottom of the storage tank, and a magnetic stirring rod corresponding to the magnetic stirrer is installed inside the storage tank; a nitrogen inlet pipe and a nitrogen outlet pipe are installed on the storage tank; the nitrogen inlet pipe is connected to a nitrogen cylinder; the flow battery pack includes an ion exchange membrane, and electrode frames, bipolar plates, and battery end plates are symmetrically arranged on both sides of the ion exchange membrane; electrodes are installed inside the electrode frames.

2. The experimental apparatus for the all-ferrous flow battery according to claim 1, characterized in that: The bipolar plate, electrode frame, and ion exchange membrane are tightly connected, forming a cavity inside the electrode frame for storing electrolyte.

3. The experimental apparatus for the all-ferrous flow battery according to claim 2, characterized in that: The battery end plate and electrode frame are provided with holes for the electrolyte inlet pipe and electrolyte return pipe to pass through, and the electrolyte inlet pipe and electrolyte return pipe are connected to the cavity where the electrolyte is stored.

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