Three-fluid-flow box-type zinc-nickel battery

Abstract

The three-fluid-flow box-type zinc-nickel battery disclosed by the present invention includes a box body, electrode plates, connection terminals, a circulation pump, and circulating electrolyte; the box body is divided into an upper box body, a main box body, and a side box body by a horizontal partition and a vertical partition, the upper box body is located at the upper part of the box body, and the main box body and the side box body are located at the lower part of the upper box body; positive and negative electrode card slots are arranged in the main box body, the electrode plates are clamped in the positive and negative electrode card slots, electrode tabs are arranged on the electrode plates, and the electrode tabs are electrically connected to the connection terminals through connecting columns; a lower liquid box inlet and a liquid box drain port are opened at the lower part of the main box body, and the lower liquid box inlet is communicated with the upper liquid box outlet through a pipeline; a lower liquid box outlet is opened at the lower part of the side box body, the circulation pump is installed on one side of the bottom of the side box body, its water inlet is connected to the lower liquid box outlet, and its water outlet is communicated with the upper liquid box inlet through a pipeline. The present invention adopts a three-liquid-box battery structure, which can effectively equalize the concentration of the electrolyte and stabilize the electrolyte liquid flow.

Description

Technical Field

[0001] The present invention belongs to the technical field of zinc-nickel batteries, and particularly relates to a three-fluid-flow box-type zinc-nickel battery. Background Art

[0002] As an energy storage battery system, the zinc-nickel flow battery has the advantages of low cost, long life, high efficiency, simple device, easy operation, no pollution, and low noise. The zinc-nickel flow battery is mainly used for the energy storage and utilization of traditional power generation modes and new power generation modes to achieve the stability of power grid transmission and the maximization of energy utilization. Among them, the electrolyte of the zinc-nickel flow battery mainly uses zincate; currently, there are problems such as uneven deposition, low energy density, and non-compact structure in the flow battery. The present invention adopts an electrolyte with three-phase flow to effectively reduce the uneven Zn deposition caused by the difference in component solubility. Summary of the Invention

[0003] The purpose of the present invention is to provide a three-fluid-flow box-type zinc-nickel battery. Through a unique structural design, the electrolyte circulation is made to flow evenly and smoothly, thereby improving the distribution of electrolyte substances and enhancing the uniformity of negative electrode deposition. At the same time, the pump and pipeline are designed laterally, making the overall structure compact.

[0004] Based on the above purpose, the present invention provides the following technical solution: A three-fluid-flow box-type zinc-nickel battery, comprising a box body, electrode plates, connection terminals, a circulation pump, and circulating electrolyte; wherein,

[0005] The box body is divided into an upper box body, a main box body, and a side box body by a horizontal partition and a vertical partition. The upper box body is located at the upper part of the box body, and the main box body and the side box body are located at the lower part of the upper box body; an opening for allowing the electrolyte to flow through is provided at the top of the vertical partition between the main box body and the side box body; a through hole is opened at each end of the upper box body, one of which is the upper liquid tank inlet, and the other is the upper liquid tank outlet; an exhaust and pressure relief hole is provided at the upper part of the upper box body;

[0006] Positive and negative electrode card slots are provided in the main box body, the electrode plates are clamped in the positive and negative electrode card slots, electrode tabs are provided on the electrode plates, and the electrode tabs are electrically connected to the connection terminals through connecting columns; a lower liquid tank inlet and a liquid tank drain port are opened at the lower part of the main box body. The lower liquid tank inlet is communicated with the upper liquid tank outlet through a pipeline, and a valve is provided on the liquid tank drain port;

[0007] A lower liquid tank outlet is opened at the lower part of the side box body, and the circulation pump is installed on one side of the bottom of the side box body; the inlet of the circulation pump is connected to the lower liquid tank outlet, and the outlet is communicated with the upper liquid tank inlet through a pipeline;

[0008] The circulating electrolyte circulates through the upper box body, the main box body and the side box body by a circulating pump; the circulating electrolyte includes KOH, NaOH and additives; the additives are one or more of cetyltrimethylammonium bromide, dodecyl bromide, indium hydroxide, lithium hydroxide, triethanolamine, polyethylene oxide, tetrabutylammonium bromide, tartaric acid, zinc oxalate, agar, sodium dihydrogen phosphate, polyvinyl alcohol and citric acid.

[0009] Preferably, the positive and negative electrode card slots are square grooves that penetrate up and down, and card slots for clamping the electrode plates are symmetrically arranged on both sides of the groove body; a notch for allowing the electrolyte in the main box body to flow into the side box body is arranged at the top of the groove body; through holes corresponding to the lower liquid tank inlet and the liquid tank drain port are also opened at the bottom of the positive and negative electrode card slots.

[0010] Preferably, the electrode plates are divided into positive electrode plates and negative electrode plates, and the positive electrode plates and negative electrode plates are alternately clamped on the positive and negative electrode card slots.

[0011] Preferably, the negative electrode plate is a punched stainless steel plate, and a tin-bismuth coating is electroplated on the punched stainless steel plate to make the deposition of zinc uniform during the later reaction; the electroplating steps are as follows: 1) Prepare a 0.1 mol / L potassium stannate solution, and add 0.05 mol / L bismuth nitrate to form a tin-bismuth solution; 2) Insert the punched stainless steel plate into the electroplating chamber, and apply a current density of 500 mA for 10 - 60 s; 3) Take out the punched stainless steel plate from the electroplating chamber to obtain a tin-bismuth plated punched stainless steel plate.

[0012] Preferably, an electrode separator is also arranged between the positive electrode plate and the negative electrode plate.

[0013] Preferably, the electrode separator is a cross-shaped or square structure composed of separator strips, and its material is PP, PC or PVC, with a thickness of 0.5 - 2 mm; the width of the separator strips is 3 - 10 mm.

[0014] Preferably, the distance between adjacent positive electrode plates and negative electrode plates is 0.2 - 0.7 mm.

[0015] In the present invention, the region where the concentration changes mainly occurs in the reaction region of the main box body; after the reaction, the electrolyte enters the side box body through the opening at the top of the vertical partition between the main box body and the side box body; after the first concentration mixing is completed in the side box body, it is pumped out from the bottom of the side box body by a circulating pump; the pumped electrolyte enters the upper box body to complete the second mixing; among them, the flow mode of the upper box body is rotational turbulence, which can better mix the electrolyte; the mixed electrolyte enters the main box body through the upper liquid tank outlet to complete the overall uniform mixing.

[0016] The beneficial effects of the present invention are:

[0017] (1)The present invention adopts a three - liquid - tank battery structure, which can effectively homogenize the concentration of the electrolyte and stabilize the electrolyte liquid flow.

[0018] (2)The present invention can expand the main electrolyte tank according to the number of electrodes. Without adjusting the positions of the side liquid phase and the pump, it can effectively simplify the assembly process and facilitate the adjustment of industrial production.

[0019] (3)The present invention makes the positive and negative stacked electrodes integral through the electrode separator and the side plate, which is convenient for the maintenance and replacement of the electrode group in the later stage. Description of the Drawings

[0020] Figure 1 is a perspective view of the present invention;

[0021] Figure 2 is a front view of the present invention;

[0022] Figure 3 is Figure 2 a view in the direction of A - A of

[0023] Figure 4 is a rear view of the present invention;

[0024] Figure 5 is Figure 4 a view in the direction of B - B of

[0025] Figure 6 is a schematic diagram of the positive and negative electrode card slots;

[0026] Figure 7 is a schematic diagram of the electrode plate;

[0027] Figure 8 is a schematic diagram of the electrode separator;

[0028] Figure 9 is a diagram of the electrode surface deposition in Example 1;

[0029] Figure 10 is a diagram of the electrode surface deposition in Comparative Example 1;

[0030] Figure 11 is a diagram of the electrode surface deposition in Comparative Example 2. Detailed Embodiments

[0031] Now, embodiments of the present invention will be described with reference to the drawings. Those skilled in the art will understand that the following embodiments are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. For those not specified in terms of specific technology, connection relationship or conditions in the embodiments, they shall be carried out according to the technology, connection relationship, conditions described in the literature in this field or according to the product specifications. For those materials, instruments or equipment not specified in terms of the manufacturer, they are all conventional products that can be obtained by purchase.

[0032] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "setting" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Combined with Figures 1-8 As shown, the three-fluid-flow box-type zinc-nickel battery provided by the present invention includes a box body, a pole piece 4, a terminal 5, a circulation pump 6, and a circulating electrolyte; wherein,

[0034] The box body is divided into an upper box body 1, a main box body 2, and a side box body 3 by a horizontal partition and a vertical partition. The upper box body 1 is located at the upper part of the box body, and the main box body 2 and the side box body 3 are located at the lower part of the upper box body 1; an opening for the electrolyte to flow through is provided at the top of the vertical partition between the main box body 2 and the side box body 3; a through hole is opened at each end of the upper box body 1, one of which is the upper liquid tank inlet and the other is the upper liquid tank outlet; an exhaust and pressure relief hole 11 is provided at the upper part of the upper box body 1; the upper box body supplies the electrolyte to the main box body to ensure the uniform flow of the electrolyte; the side box body mainly caches the electrolyte and pumps the electrolyte back to the upper box body through a circulation pump;

[0035] The main box body 2 is a positive and negative electrode reaction box body. Positive and negative electrode slots 21 are provided in the main box body 2, and the pole piece 4 is clamped in the positive and negative electrode slots 21. A pole ear 41 is provided on the pole piece 4, and the pole ear 41 is electrically connected to the terminal 5 through a connecting column; the pole ear 41 is made of a stainless steel strip, a nickel-plated copper strip, or a nickel-plated stainless steel strip, and the width is 5 - 20 mm; a lower liquid tank inlet and a liquid tank drain port are opened at the lower part of the main box body 2. The lower liquid tank inlet is communicated with the upper liquid tank outlet through a pipeline, and a valve is provided on the liquid tank drain port;

[0036] A lower liquid tank outlet is opened at the lower part of the side box body 3, and the circulation pump 6 is installed on one side of the bottom of the side box body 3; the water inlet of the circulation pump 6 is connected to the lower liquid tank outlet, and the water outlet is communicated with the upper liquid tank inlet through a pipeline;

[0037] The circulating electrolyte circulates in the upper box body 1, the main box body 2, and the side box body 3 through the circulation pump 6; the circulating electrolyte in the present invention is a potassium hydroxide solution containing 20 - 40 g / L of ZnO, wherein the molar concentration of potassium hydroxide is 4 - 8 mol / L, and an additive is added to the electrolyte. The additive is one or several of cetyltrimethylammonium bromide, dodecyl bromide, indium hydroxide, lithium hydroxide, triethanolamine, polyethylene oxide, tetrabutylammonium bromide, tartaric acid, zinc oxalate, agar, sodium dihydrogen phosphate, polyvinyl alcohol, and citric acid, so as to improve its hydrogen evolution potential and cycle life.

[0038] Specifically, the positive and negative electrode card slots 21 are square slots that penetrate up and down. On both sides of the slot body, card slots 22 for clamping the electrode plates 4 are symmetrically arranged, and the width of the card slots 22 is 2 - 4 mm; at the top of the slot body, there is a notch 23 for allowing the electrolyte in the main box body 2 to flow into the side box body 3; at the bottom of the positive and negative electrode card slots 21, through holes corresponding to the lower liquid tank inlet and the liquid tank drain port are also provided.

[0039] In a further optimized solution, the electrode plates 4 are divided into positive electrode plates and negative electrode plates, and the positive electrode plates and negative electrode plates are alternately clamped on the positive and negative electrode card slots 21; the distance between adjacent positive electrode plates and negative electrode plates is 0.2 - 0.7 mm to obtain a high energy density; an electrode separator 7 is also arranged between the positive electrode plates and negative electrode plates; the electrode separator 7 is in a cross-shaped or square structure composed of separator strips, and its material is PP, PC or PVC, with a thickness of 0.5 - 2 mm; the width of the separator strips is 3 - 10 mm; the main function of the electrode separator 7 is to prevent the deformation of the electrodes and enhance their stability.

[0040] In a further optimized solution, the negative electrode plate is a punched stainless steel plate, and a tin - bismuth coating is electroplated on the punched stainless steel plate to facilitate the uniform deposition of zinc during the later reaction process; the electroplating steps are as follows: 1. Prepare a 0.1 mol / L potassium stannate solution and add 0.05 mol / L bismuth nitrate to form a tin - bismuth solution; 2. Insert the punched stainless steel plate into the electroplating chamber and apply a current density of 500 mA for 10 - 60 s; 3. Take out the punched stainless steel plate from the electroplating chamber to obtain a tin - bismuth - plated punched stainless steel plate.

[0041] In one embodiment, the box body in the present invention can also be composed of 1 closed cube and 1 cube with an open top. The cube with an open top is divided into a main box body and a side box body by a partition, and the closed cube serves as the upper box body; the closed cube is fixed on the cube with an open top through a plurality of positioning cards, and other structures are the same as those described above.

[0042] The charge - discharge cycle process of the present invention: The electrolyte is pumped from the side box body to the upper box body through the circulation pump installed at the lower part of the side box body, and the pipeline connected to the upper liquid tank outlet of the upper box body allows the electrolyte to flow from the upper box body into the main box body. The electrolyte slowly flows upward from the bottom of the main box body until it submerges the electrodes and flows into the side box body along the notch provided at the top of the positive and negative electrode card slots. The flow rate of the liquid in the main box body depends on the height of the upper box body and the opening size of the upper liquid tank outlet. A low flow rate will reduce the requirements for the circulation pump (there is a certain proportional relationship between the power and volume of the pump, for example, the power of a 12A water pump is 9W, the power of a 50A water pump is 110W, and the power of an 80A water pump is 150W). Embodiment

[0043] Under the condition of the circulating flow of three liquid tanks, the circulating electrolyte is 6M KOH, 30 - 35 g / L of ZnO and CTHB; the sintered nickel electrode is used as the positive electrode; the results are as Figure 9 shown in Table 1; the charge-discharge efficiency gradually increases from the first discharge to 99%, and the deposition on the electrode deposition surface is significantly denser.

[0044] Table 1

[0045]

[0046] Comparative Example 1

[0047] Under the condition of static non-flow, the electrolyte is 6M KOH, 30 - 35 g / L of ZnO and CTHB; the sintered nickel electrode is used as the positive electrode; the results are as Figure 10 shown in Table 2; the charge-discharge efficiency fluctuates to some extent, which is mainly related to the uniformity of the deposition surface. The deposition is mainly concentrated in the lower part and is in a fluffy state.

[0048] Table 2

[0049]

[0050] Comparative Example 2

[0051] Under the condition of the up-and-down circulating flow of a single liquid tank, the electrolyte is 6M KOH, 30 - 35 g / L of ZnO and CTHB; the sintered nickel electrode is used as the positive electrode; the results are as Figure 11 shown in Table 3; the charge-discharge efficiency is above 90%, and the uniformity of the electrode deposition surface is improved, but the deposition effect is still in a fluffy state.

[0052] Table 3

[0053]

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any minor modifications, equivalent replacements, and improvements made to the above embodiments based on the technical essence of the present invention should be included within the protection scope of the technical solution of the present invention.

Claims

1. Three-fluid-flow box-type zinc-nickel battery, characterized in that, It includes a box body, electrode plates (4), terminal blocks (5), a circulation pump (6) and circulating electrolyte; among which, The box body is divided into an upper box body (1), a main box body (2) and a side box body (3) by a horizontal partition board and a vertical partition board. The upper box body (1) is located at the upper part of the box body, and the main box body (2) and the side box body (3) are located at the lower part of the upper box body (1); there is an opening for the electrolyte to flow through at the top of the vertical partition board between the main box body (2) and the side box body (3); there is a through hole at each end of the upper box body (1), one of which is the upper liquid tank inlet and the other is the upper liquid tank outlet; an exhaust pressure relief hole (11) is arranged at the upper part of the upper box body (1); Positive and negative electrode card slots (21) are arranged in the main box body (2), the electrode plates (4) are clamped in the positive and negative electrode card slots (21), electrode tabs (41) are arranged on the electrode plates (4), and the electrode tabs (41) are electrically connected to the terminal blocks (5) through connecting columns; a lower liquid tank inlet and a liquid tank drain port are arranged at the lower part of the main box body (2), the lower liquid tank inlet is communicated with the upper liquid tank outlet through a pipeline, and a valve is arranged on the liquid tank drain port; A lower liquid tank outlet is arranged at the lower part of the side box body (3), and the circulation pump (6) is installed on one side of the bottom of the side box body (3); the water inlet of the circulation pump (6) is connected to the lower liquid tank outlet, and the water outlet is communicated with the upper liquid tank inlet through a pipeline; The circulating electrolyte circulates in the upper box body (1), the main box body (2) and the side box body (3) through the circulation pump (6); the circulating electrolyte includes KOH, NaOH and additives; the additives are one or several of cetyltrimethylammonium bromide, dodecyl bromide, indium hydroxide, lithium hydroxide, triethanolamine, polyethylene oxide, tetrabutylammonium bromide, tartaric acid, zinc oxalate, agar, sodium dihydrogen phosphate, polyvinyl alcohol and citric acid; The electrolyte is pumped from the side box body to the upper box body through the circulation pump installed at the lower part of the side box body, and the pipeline communicated with the upper liquid tank outlet of the upper box body enables the electrolyte to flow from the upper box body into the main box body. The electrolyte slowly flows upward from the bottom of the main box body until it overflows the electrodes and flows into the side box body along the notch arranged at the top of the positive and negative electrode card slots.

2. The three-fluid-flow box-type zinc-nickel battery according to claim 1, wherein The positive and negative electrode card slots (21) are square groove bodies that penetrate up and down. Card slots (22) for clamping the electrode plates (4) are symmetrically arranged on both sides of the groove body; a notch (23) for allowing the electrolyte in the main box body (2) to flow into the side box body (3) is arranged at the top of the groove body; through holes corresponding to the lower liquid tank inlet and the liquid tank drain port are also arranged at the bottom of the positive and negative electrode card slots (21).

3. The three-fluid-flow box-type zinc-nickel battery according to claim 1 or 2, characterized in that, The electrode plates (4) are divided into positive electrode plates and negative electrode plates, and the positive electrode plates and the negative electrode plates are alternately clamped on the positive and negative electrode card slots (21).

4. The three-liquid-flow box-type zinc-nickel battery according to claim 3, wherein, The negative electrode plate is a punched stainless steel plate, and a tin-bismuth coating is electroplated on the punched stainless steel plate to make the deposition of zinc uniform during the later reaction process; the electroplating steps are as follows: 1) Prepare a 0.1mol / L potassium stannate solution and add 0.05mol / L bismuth nitrate to form a tin-bismuth solution; 2) Insert the punched stainless steel plate into the electroplating chamber and apply a current density of 500mA for 10 - 60s; 3) Take out the punched stainless steel plate from the electroplating chamber to obtain a tin-bismuth plated punched stainless steel plate.

5. The three-liquid-flow box-type zinc-nickel battery according to claim 3, characterized in that, An electrode separator (7) is also provided between the positive electrode plate and the negative electrode plate.

6. The three-liquid-flow box-type zinc-nickel battery according to claim 5, wherein, The electrode separator (7) is in a cross-shaped or square structure composed of separator strips, and its material is PP, PC or PVC, with a thickness of 0.5 - 2 mm; the width of the separator strip is 3 - 10 mm.

7. The three-liquid-flow box-type zinc-nickel battery according to claim 3, wherein The distance between adjacent positive electrode plates and negative electrode plates is 0.2 - 0.7 mm.

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