CN112864437B - A kind of iron-lead single flow battery and preparation method thereof - Google Patents

Abstract

The invention provides an iron-lead single flow battery and a preparation method thereof, wherein the battery comprises an iron-lead single flow battery structure, and the iron-lead single flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer which are sequentially arranged; and the negative electrode material layer is filled with negative electrolyte, the positive electrode material layer is filled with positive electrolyte, and the positive electrolyte circularly flows in the positive electrode material layer. According to the invention, the all-solid-state lead negative electrode and the soluble iron salt positive electrode are combined into the single flow battery for the first time, so that the generation of lead crystal branches is effectively avoided, and the battery performance is obviously improved.

Description

A kind of iron-lead single flow battery and preparation method thereof

technical field

The invention relates to the technical field of liquid flow batteries, in particular to an iron-lead single liquid flow battery and a preparation method thereof.

Background technique

With the increasingly prominent environmental problems and energy problems, the demand for clean and renewable energy is increasing. As one of the energy storage technologies in the utilization of new energy, batteries have attracted more and more attention. Among them, flow battery is a new type of battery technology. Compared with existing batteries such as lead-acid batteries and lithium batteries, it has the advantages of long life, safety and environmental protection, independent design of capacity and power, and deep charge and discharge. It is especially suitable for large batteries. Scale energy storage. Among the existing flow battery technologies, the all-vanadium flow battery is a typical representative, and its performance indicators have met the requirements of the application. However, the all-vanadium redox flow battery uses vanadium as the energy storage active material, the positive electrode uses a solution of tetravalent vanadium ions and pentavalent vanadium ions as the energy storage material, and the negative electrode uses a solution of trivalent vanadium and divalent vanadium ions as the energy storage material . Due to insufficient reserves of vanadium resources and high production and manufacturing costs, the cost of all-vanadium redox flow batteries remains high, which has become a bottleneck for its large-scale application. In order to solve the cost problem, scientists and engineers have begun to focus on using cheap metal elements as energy storage materials, such as all-iron flow batteries and all-lead flow batteries (Journal of the Electrochemical Society, 1987, 134(12):3083-9) . The negative electrode of the all-iron flow battery uses metallic iron and divalent iron ion solution as the energy storage material, and the positive electrode uses the solution of divalent iron ion and trivalent iron ion as the energy storage material. However, the negative electrode of all-iron flow batteries will produce a large number of hydrogen evolution reactions during the charging process, resulting in irreversible charge-discharge reactions and low energy conversion efficiency, which has always hindered the practical application of all-iron flow batteries (Journal of The Electrochemical Society, 2014, 161(10):A1662-A71). All-lead flow batteries use lead as an energy storage material. In this battery, a divalent soluble lead salt (such as lead methanesulfonate) undergoes a redox reaction with metallic lead at the negative electrode, and the divalent soluble lead salt is oxidized at the positive electrode. into lead peroxide. Although all-lead flow batteries can use cheap lead as an energy storage element, there are currently two technical problems in all-lead flow batteries, which prevent them from being practically applied: 1) The problem of negative electrode dendrites. The reduction reaction of the negative electrode is that the soluble divalent lead salt solution is reduced to the metal lead element. During the reduction process, the metal lead will form dendrites toward the positive electrode, resulting in a short circuit of the internal battery. 2) The problem that the positive lead peroxide falls off. The lead peroxide generated from the positive electrode is easily detached from the electrode, which seriously affects the performance of the battery (Journal of Energy Storage 15 (2018) 69–90). In traditional lead-acid batteries, both positive and negative electrodes use solid lead-containing substances that are insoluble in the electrolyte as active materials. The negative electrode is the redox reaction of lead sulfate and lead, and the positive electrode is the redox reaction of lead sulfate and lead peroxide. However, a common problem of lead-acid batteries is that in the process of charging and discharging, the negative electrode produces irreversible lead sulfate crystals, which leads to a significant decrease in capacity and a relatively short cycle life, which cannot meet the life requirements of large-scale energy storage. In addition, the charge-discharge rate of lead-acid batteries is relatively low, and the charge-discharge rate is usually less than 0.2C for a long time. Only Zhao et al. proposed the concept of iron-lead flow battery (Journal of PowerSources 346 (2017) 97-102): the negative electrode utilizes the redox reaction between soluble divalent lead salt solution and metallic lead, and the positive electrode utilizes soluble divalent lead salt solution. Valence iron salts and ferric salts are used as energy storage materials. There are two problems in this battery: 1) Since the negative electrode is reduced to metal lead in a soluble lead salt solution, the current technology cannot avoid the formation of lead dendrites, and there is a risk of internal short circuit 2) The theoretical voltage of the battery is only 0.9V, and the voltage is low. Therefore, the value of practical application is lacking.

To sum up, traditional flow batteries, including full flow batteries (active energy storage material circulating on two electrodes) and single flow battery (active energy storage material circulating on one electrode), currently exist. The issue of cost or performance leads us to urgently develop a large-scale energy storage battery with low cost and performance that can meet the requirements of energy storage to meet our needs for the utilization of clean and renewable energy.

SUMMARY OF THE INVENTION

In view of the deficiencies in the prior art, the purpose of the present invention is to provide an iron-lead single-flow battery and a preparation method thereof.

The purpose of this invention is to realize through the following technical solutions:

The invention provides an iron-lead single-flow battery structure, which includes a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with negative electrode electrolyte. Filling the positive electrode electrolyte, and the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer includes two or three components of lead element, solid divalent lead salt and conductive agent;

The negative electrode electrolyte is an inorganic acid aqueous solution;

the positive electrode material layer is a porous carbon electrode layer;

The positive electrode electrolyte includes a mixed aqueous solution formed by a trivalent iron salt solution, a divalent iron salt and an inorganic acid.

Preferably, additives, such as bismuth oxide, barium sulfate, humic acid, gallium oxide, indium oxide, etc., may be added to the negative electrode material layer, but not limited to this;

Additives, such as methanesulfonic acid, magnesium sulfate, sodium fluoride, etc., may also be added to the negative electrolyte, but are not limited thereto.

Additives, such as ammonium sulfate, ammonium chloride, potassium sulfate, potassium chloride, etc., may also be added to the positive electrode electrolyte, but are not limited thereto.

Preferably, the solid divalent lead salt is one or both of lead sulfate and lead chloride;

The conductive agent is one or a combination of conductive carbon black, graphene, carbon powder, carbon nanotube, carbon fiber, and copper.

Preferably, in the negative electrode material layer, the total mass of elemental lead and solid divalent lead salt is 20-100% of the mass of the electrode material layer, more preferably 50-95%, and most preferably 65-85%.

More preferably, in the negative electrode material layer, the mass percentage content of the conductive agent is 2-35%.

Preferably, the solid divalent lead salt is selected from lead sulfate and lead chloride.

Preferably, the negative electrode material layer further contains a binder.

Preferably, the thickness of the negative electrode material layer is 0.5-20 mm, more preferably 1-5 mm thick, and most preferably 1.5-3 mm thick; the negative electrode material layer is a porous solid-state electrode, the holes are open pores, and the electrolyte can enter the inside of the electrode, The porosity is 10%-80%, more preferably the porosity is 30%-60%.

Preferably, the porous carbon electrode layer is one or a combination of carbon felt, carbon paper, carbon cloth, and porous carbon plate;

The ferric salt is one or two combinations of ferrous sulfate and ferrous chloride, and the ferric salt is one or two combinations of ferric sulfate and ferric chloride;

Described inorganic acid is one or two combinations in sulfuric acid or hydrochloric acid;

The ion-selective membrane is one or more combinations of ion-exchange resin membranes, porous polymer membranes, and swollen polymer membranes; The electrolyte of the negative electrode prevents cross flow, and at the same time has the function of conducting protons, so as to balance the ions between the positive and negative electrodes, so that the charge-discharge reaction can continue.

Preferably, the mass fraction of the inorganic acid aqueous solution is 3-20%.

或者负极充放电反应为铅单质和氯化铅的氧化还原反应，反应方程式为：

采用的正极材料层与正极电解液形成的正极的充放电反应为三价铁盐溶液和二价铁盐进行氧化还原反应，反应方程式为：

The charge-discharge reaction of the negative electrode formed by the negative electrode material layer and the negative electrode electrolyte used in the present invention is the redox reaction of lead element and lead sulfate, and the reaction equation is:

Or the negative electrode charge-discharge reaction is the redox reaction of lead element and lead chloride, and the reaction equation is:

The charge-discharge reaction of the positive electrode formed by the positive electrode material layer and the positive electrode electrolyte is that the trivalent iron salt solution and the divalent iron salt carry out the redox reaction, and the reaction equation is:

The charge-discharge reaction of the iron-lead single-flow battery structure is:

或者：

or:

The present invention also provides an iron-lead single-flow battery, comprising the aforementioned iron-lead single-flow battery structure, and further comprising a positive electrode plate, a positive electrode plate frame, a negative electrode plate, a negative electrode plate frame and an end plate;

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and end plates are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged around the negative electrode material layer, and a positive electrode plate frame is arranged around the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, a circulating pump is provided on the pipeline;

Both the positive electrode plate and the negative electrode plate are made of metal or carbon material;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas;

A current collector plate is also arranged between the positive electrode plate and the end plate and between the negative electrode plate and the end plate; the current collector plate is made of metal or carbon material.

Preferably, the current collector plate and the positive electrode plate, the current collector plate and the negative electrode plate can be integrated respectively; or the positive plate frame and the positive plate, the negative plate frame and the negative plate can be integrated respectively; The frame and the positive plate, the collector plate, the negative plate frame and the negative plate can be integrated respectively.

The present invention also provides an iron-lead single-flow battery stack, which is composed of the aforementioned iron-lead single-flow battery structure in a series and/or parallel manner.

Preferably, when the iron-lead single-flow battery structure is formed in series, it further includes a positive electrode plate, a positive electrode plate frame, a negative electrode plate, a negative electrode plate frame, a bipolar plate and an end plate;

A bipolar plate is arranged between each of the iron-lead single-flow battery structures, the negative plate is arranged on the outer side of the outermost negative electrode material layer, the positive plate is arranged on the outer side of the outermost positive electrode material layer, and the An end plate is respectively arranged on the outer side of the anode material layer; a negative plate frame is arranged around the negative electrode material layer, and a positive plate frame is arranged around the positive electrode material layer; a pipeline is arranged on the positive plate frame, and the other end of the pipeline is connected to the anode electrolyte storage tank;

When the iron-lead single-flow battery structure is formed in parallel, every two positive electrodes share one negative electrode; the specific structural unit includes a positive electrode material layer, an ion selective permeation membrane, a negative electrode material layer, and an ion selective permeation layer arranged in sequence. membrane and positive electrode material layer; also include positive electrode plates and end plates arranged in sequence outside the positive electrode material layers on both sides; the negative electrode plate frame is respectively provided with a negative electrode plate, a channel for supplementing the negative electrode electrolyte and exhaust gas, so The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, when the iron-lead single-flow battery structure is formed in a parallel manner, a current collector plate is further arranged between the positive electrode plate and the end plate.

Although the battery proposed by the present invention, the reaction principle of its positive and negative electrodes is not the first to be discovered and applied. However, the combination of an all-solid-state lead negative electrode and a soluble iron salt positive electrode into a single-flow battery is the first proposal of the present invention, which can effectively solve the problem of dendrite growth during the reduction process of the negative electrode soluble lead salt. A large number of experiments and improvements have been carried out on the structure, such as the unique design of the porous 3D electrode and the innovative design and optimization of the composition of the negative electrode material, which significantly improves the rate performance and capacity of the negative electrode, and the charge-discharge stability is also significantly improved. At the same time, the problem of the rapid capacity decrease caused by the continuous and significant formation of irreversible lead sulfate crystals in the redox process between the solid divalent lead salt and the metallic lead is solved. The high-performance, low-cost energy storage battery described in the present invention cannot be obtained by simply recombining existing battery technologies. For example, the negative electrode of a commercial lead-acid battery [the negative electrode is, sponge-like fibrous active material (solid divalent lead salt and metallic lead) coated on a lead-antimony-calcium alloy grid] and the positive electrode of an all-iron flow battery ( Soluble divalent iron salt and trivalent iron salt) are assembled into a single flow battery according to the battery structure described in the present invention. The test results show that the capacity of the battery drops by more than 30% after 10 times of charge and discharge, which cannot meet the application requirements. .

Compared with the prior art, the present invention has the following beneficial effects:

1) The present invention effectively avoids the formation of lead crystal branches by combining an all-solid lead negative electrode and a soluble iron salt positive electrode into a single-flow battery for the first time.

2) The theoretical voltage of the iron-lead single-flow battery prepared by the invention can be as high as: 1.13V; after 300 cycles of charging and discharging, no obvious dendrites are formed in the negative electrode.

3) Under the 0.5C rate, the iron-lead single flow battery prepared by the present invention can achieve a current efficiency of over 99% and an energy efficiency of over 90%; under a 3C rate, the current efficiency can reach over 99% and the energy efficiency can reach over 99%. 80%; capacity decay can be less than 2% after 100 times of charge and discharge.

Description of drawings

Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings:

Fig. 1 is the iron-lead single flow battery structure of the embodiment 1 of the present invention;

Fig. 2 is the iron-lead single-flow battery structure of the embodiment 2 of the present invention;

Fig. 3 is the iron-lead single-flow battery stack structure according to Embodiment 3 of the present invention;

FIG. 4 is the structure of the iron-lead single-flow battery stack according to the fourth embodiment of the present invention.

Detailed ways

The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Example 1

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 1 , including an iron-lead single-flow battery structure, and also includes a positive plate, a positive plate frame, a negative plate, a negative plate frame, a collector plate, a terminal plate;

The iron-lead single-flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with positive electrode electrolyte, And the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer is composed of 60% metal lead, 25% lead sulfate and 15% acetylene black by mass fraction;

The negative electrode electrolyte is an aqueous solution of sulfuric acid, and the mass fraction of sulfuric acid is 10%;

The positive electrode material layer is a porous carbon electrode layer, specifically a graphite felt;

The positive electrode electrolyte is a mixed aqueous solution formed by ferric sulfate, ferrous sulfate and sulfuric acid (mass ratio is 1:8:1).

The ion selective membrane is a perfluorosulfonic acid membrane;

The thickness of the negative electrode material layer is 1.5 mm, the negative electrode material layer is a porous solid electrode material layer, the pores are open pores, the electrolyte can enter the inside of the electrode, and the porosity is 50%.

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and a current collector plate and an end plate are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged on the outer side of the negative electrode material layer, and a positive electrode plate frame is arranged on the outer side of the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

A circulating pump is arranged on the pipeline;

The current collecting plate is made of copper plate, and the positive plate and the negative plate are all made of graphite material;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 90%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 80%; the capacity decay can be less than 2% after 100 times of charge and discharge.

Example 2

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 2 , the difference from Embodiment 1 is that the negative electrode plate frame is not provided with a channel for supplementing the negative electrode electrolyte and exhaust gas. The negative electrode electrolyte is added to the negative electrode filler layer in advance.

The performance of the battery prepared in this example is similar to that of Example 1.

Example 3

This embodiment provides an iron-lead single-flow battery stack, as shown in FIG. 3 . Using the iron-lead single-flow battery structure described in Example 1, a bipolar plate is arranged between each of the iron-lead single-flow battery structures, the negative plate is arranged outside the outermost negative electrode material layer, and the positive plate is arranged On the outside of the outermost positive electrode material layer, a current collector plate and an end plate are respectively arranged on the outside of the negative electrode plate and the positive electrode plate; negative electrode plate frames are arranged at the upper and lower ends of the negative electrode material layer, A positive plate frame is arranged at the part; a pipeline is arranged on the positive plate frame, and the other end of the pipeline is connected to the positive electrolyte storage tank;

A circulating pump is arranged on the pipeline;

The current collector plate is made of copper plate, and the positive plate and the negative plate are all made of graphite;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery stack obtained in this example is the sum of the theoretical voltages of several single cells, and other properties are similar to those in Example 1.

Example 4

This embodiment provides an iron-lead single-flow battery stack. As shown in FIG. 4 , every two positive electrodes share one negative electrode; the specific structural unit includes a positive electrode material layer, an ion selective permeation membrane, and a negative electrode material layer arranged in sequence. , ion selective permeable membrane, positive electrode material layer (the specific materials used in each layer are the same as in Example 1); also include positive electrode plates, current collector plates, and end plates that are sequentially arranged outside the positive electrode material layers on both sides; the negative electrode A negative electrode plate, a channel for supplementing the negative electrode electrolyte and exhaust gas are respectively arranged on the plate frame, a pipeline is arranged on the positive plate frame, and the other end of the pipeline is connected to the positive electrode electrolyte liquid storage tank;

A circulating pump is arranged on the pipeline;

The current collector plate is made of copper plate, and the positive plate and the negative plate are all made of graphite;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery stack obtained in this example is the same as the theoretical voltage of the single cell, the current is the sum of the currents of several single cells, and other properties are similar to those in Example 1.

Example 5

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 1 , including an iron-lead single-flow battery structure, and also includes a positive plate, a positive plate frame, a negative plate, a negative plate frame, a collector plate, a terminal plate;

The iron-lead single-flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with positive electrode electrolyte, And the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer is composed of 60% metal lead, 20% lead sulfate and 20% graphite powder by mass fraction;

The negative electrode electrolyte is an aqueous solution of sulfuric acid, and the mass fraction of sulfuric acid is 5%;

The positive electrode material layer is a porous carbon electrode layer, specifically a graphite felt;

The positive electrode electrolyte is a mixed aqueous solution formed by ferric sulfate, ferrous sulfate and sulfuric acid (mass ratio is 4:5:1).

The ion selective membrane is a perfluorosulfonic acid membrane;

The thickness of the negative electrode material layer is 0.5 mm, the negative electrode material layer is a porous solid electrode, the pores are open pores, the electrolyte can enter the inside of the electrode, and the porosity is 10%.

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and a current collector plate and an end plate are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged on the outer side of the negative electrode material layer, and a positive electrode plate frame is arranged on the outer side of the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, a circulating pump is provided on the pipeline;

The current collecting plate is made of copper plate, and the positive plate and the negative plate are all made of graphite material;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 97%, and the energy efficiency can reach more than 85%; 3C rate The current efficiency can reach more than 98%, and the energy efficiency can reach 81%; the capacity decay can be less than 3% after 100 times of charge and discharge.

Example 6

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 1 , including an iron-lead single-flow battery structure, and also includes a positive electrode plate, a positive electrode plate frame, a negative electrode plate, a negative electrode plate frame, and an end plate;

The iron-lead single-flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with positive electrode electrolyte, And the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer is composed of 70% metal lead, 28% lead sulfate and 2% carbon nanotubes by mass fraction;

The negative electrode electrolyte is an aqueous solution of sulfuric acid, and the mass fraction of sulfuric acid is 3%;

The positive electrode material layer is a porous carbon electrode layer, specifically carbon paper;

The positive electrode electrolyte is a mixed aqueous solution formed by ferric sulfate, ferrous sulfate and sulfuric acid (mass ratio is 2:7:1).

The ion selective membrane is a perfluorosulfonic acid membrane;

The thickness of the negative electrode material layer is 20 mm, the negative electrode material layer is a porous solid electrode, the pores are open pores, the electrolyte can enter the inside of the electrode, and the porosity is 80%.

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and a current collector plate and an end plate are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged on the outer side of the negative electrode material layer, and a positive electrode plate frame is arranged on the outer side of the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, a circulating pump is provided on the pipeline;

The positive electrode plate and the negative electrode plate are both made of graphite material;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 97%, and the energy efficiency can reach more than 86%; 3C rate The current efficiency can reach more than 98%, and the energy efficiency can reach 83%; the capacity decay can be less than 2.8% after 100 times of charge and discharge.

Example 7

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 1 , including an iron-lead single-flow battery structure, and also includes a positive plate, a positive plate frame, a negative plate, a negative plate frame, a collector plate, a terminal plate;

The iron-lead single-flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with positive electrode electrolyte, And the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer is composed of 68% metal lead, 27% lead chloride and 5% conductive carbon black by mass fraction;

The negative electrode electrolyte is an aqueous solution of hydrochloric acid, and the mass fraction of hydrochloric acid is 15%;

The positive electrode material layer is a porous carbon electrode layer, specifically carbon cloth;

The positive electrode electrolyte is a mixed aqueous solution formed by ferric chloride, ferrous chloride and hydrochloric acid (mass ratio is 6:3:1).

The ion selective membrane is a porous polyvinylidene fluoride membrane;

The thickness of the negative electrode material layer is 10 mm, the negative electrode material layer is a porous solid-state electrode, the pores are open pores, the electrolyte can enter the inside of the electrode, and the porosity is 33%.

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and a current collector plate and an end plate are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged on the outer side of the negative electrode material layer, and a positive electrode plate frame is arranged on the outer side of the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, a circulating pump is provided on the pipeline;

The current collecting plate is made of copper plate, and the positive plate and the negative plate are all made of graphite material;

The negative plate frame is provided with a channel for supplementing the negative electrolyte and exhaust gas.

The theoretical voltage of the battery prepared in this example is: 1.04V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 89%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 86%; the capacity decay can be less than 2.5% after 100 times of charge and discharge.

Example 8

This embodiment provides an iron-lead single-flow battery, as shown in FIG. 1 , including an iron-lead single-flow battery structure, and also includes a positive plate, a positive plate frame, a negative plate, a negative plate frame, a collector plate, a terminal plate;

The iron-lead single-flow battery structure comprises a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer arranged in sequence; the negative electrode material layer is filled with negative electrode electrolyte, and the positive electrode material layer is filled with positive electrode electrolyte, And the positive electrode electrolyte circulates in the positive electrode material layer;

The negative electrode material layer is composed of 45% metal lead, 20% lead chloride and 35% copper powder by mass fraction;

The negative electrode electrolyte is an aqueous solution of hydrochloric acid, and the mass fraction of hydrochloric acid is 20%;

The positive electrode material layer is a porous carbon electrode layer, specifically a porous carbon plate;

The positive electrode electrolyte is a mixed aqueous solution formed by ferric chloride, ferrous chloride and hydrochloric acid (mass ratio is 3:6:1).

The ion selective membrane is a swollen sulfonated polyethersulfone membrane;

The thickness of the negative electrode material layer is 2 mm, the negative electrode material layer is a porous solid-state electrode, the pores are open pores, the electrolyte can enter the inside of the electrode, and the porosity is 46%.

The negative electrode plate is arranged on the outer side of the negative electrode material layer, the positive electrode plate is arranged on the outer side of the positive electrode material layer, and a current collector plate and an end plate are respectively arranged on the outer side of the negative electrode plate and the positive electrode plate;

A negative electrode plate frame is arranged on the outer side of the negative electrode material layer, and a positive electrode plate frame is arranged on the outer side of the positive electrode material layer;

The positive plate frame is provided with a pipeline, and the other end of the pipeline is connected to the positive electrolyte liquid storage tank.

Preferably, a circulating pump is provided on the pipeline;

The current collecting plate is made of copper plate, and the positive plate and the negative plate are all made of graphite material;

The negative plate frame is provided with a channel for supplementing negative electrolyte and exhaust gas.

The theoretical voltage of the battery prepared in this example is: 1.04V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 85%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 82%; the capacity decay can be less than 4% after 100 times of charge and discharge.

Example 9

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 6, the only difference is that the negative electrode material layer is composed of 70% metal lead and 30% lead sulfate by mass fraction.

The performance of the battery prepared in this example: the theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency is 95.9%, and the energy efficiency is 76% %; under 3C rate, the current efficiency can reach 96.4%, and the energy efficiency can reach 63%; the capacity decay is 50.2% after 100 times of charge and discharge.

Example 10

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 8, the only difference is: the negative electrode material layer is composed of 42% metal lead, 18% lead chloride and 40% copper powder composition.

The performance of the battery prepared in this example: the theoretical voltage of the battery prepared in this example is: 1.04V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency At 3C rate, the current efficiency can reach more than 97%, and the energy efficiency can reach 65%; the capacity decay is 7.2% after 100 times of charge and discharge.

Example 11

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is: the negative electrode material layer is composed of 60% metal lead, 25% lead sulfate and 15% lead sulfate by mass fraction. % graphite powder composition.

The performance of the battery prepared in this example: the theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 98%, and the energy efficiency At 3C rate, the current efficiency can reach more than 99%, and the energy efficiency can reach 79%; the capacity decay is 2.8% after 100 times of charge and discharge.

Example 12

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is: the negative electrode material layer is composed of 60% metal lead, 25% lead sulfate and 15% lead sulfate by mass fraction. % Carbon fiber composition.

The performance of the battery prepared in this example: the theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 97%, and the energy efficiency It can reach more than 83%; at 3C rate, the current efficiency can reach more than 99%, and the energy efficiency can reach 77%; the capacity decay can be less than 3.3% after 100 times of charge and discharge.

Example 13

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is: the negative electrode material layer is composed of 60% metal lead, 25% lead sulfate and 15% lead sulfate by mass fraction. % copper powder composition.

The performance of the battery prepared in this example: the theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency It can reach more than 85%; under 3C rate, the current efficiency can reach more than 99%, and the energy efficiency can reach 76%; the capacity decay can be less than 5.6% after 100 times of charge and discharge.

Example 14

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is that the thickness of the negative electrode material layer is 0.5 mm.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 90%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 80%; the capacity decay can be less than 2% after 100 times of charge and discharge. However, compared with Example 1, the discharge capacity of the negative electrode is only 48% of that of Example 1.

Example 15

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the difference is only that the thickness of the negative electrode material layer is 1.0 mm.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 90%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 80%; the capacity decay can be less than 2% after 100 times of charge and discharge. However, compared with Example 1, the discharge capacity of the negative electrode is only 78% of that of Example 1.

Example 16

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, and the difference is only that the thickness of the negative electrode material layer is 4.0 mm.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 98%, and the energy efficiency can reach more than 86%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 77%; the capacity decay can be less than 2% after 100 times of charge and discharge. Compared with Example 1, the discharge capacity of the negative electrode is 1.6 times that of Example 1.

Example 17

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is that the thickness of the negative electrode material layer is 20 mm.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 82%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 73%; the capacity decay can be less than 2% after 100 times of charge and discharge. Compared with Example 1, the discharge capacity of the negative electrode is 3.2 times that of Example 1.

Example 18

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the only difference is that the filling porosity of the negative electrode material layer is 20%.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at 0.5C rate, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 85%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 76%; the capacity decay can be less than 2% after 100 times of charge and discharge.

Example 19

This embodiment provides an iron-lead single-flow battery, the structure is basically the same as that of Embodiment 1, the difference is only that the filling porosity of the negative electrode material layer is 80%.

The theoretical voltage of the battery prepared in this example is: 1.13V; after 300 cycles of charge and discharge, there is no obvious dendrite formation in the negative electrode; at a rate of 0.5C, the current efficiency can reach more than 99%, and the energy efficiency can reach more than 84%; 3C rate The current efficiency can reach more than 99%, and the energy efficiency can reach 75%; the capacity decay can be less than 2% after 100 times of charge and discharge.

It should be noted that the iron-lead single-flow battery of the present invention is not limited to those prepared by the methods of the above-mentioned embodiments. For example, a binder can be added to the negative electrode material layer, and an additive such as bismuth oxide can also be added to the negative electrode material layer. , barium sulfate, humic acid, gallium oxide, indium oxide, etc., but not limited to this; additives such as methanesulfonic acid, magnesium sulfate, sodium fluoride, etc. can also be added to the negative electrolyte, but not limited to this; Additives, such as ammonium sulfate, ammonium chloride, potassium sulfate, potassium chloride, etc., may also be added to the positive electrolyte, but are not limited thereto. The iron-lead single-flow battery prepared in this way can also achieve the effect of the present invention.

The foregoing description of the embodiments is provided to facilitate understanding and use of the invention by those of ordinary skill in the art. It will be apparent to those skilled in the art that various modifications to these embodiments can be readily made, and the generic principles described herein can be applied to other embodiments without inventive step. Therefore, the present invention is not limited to the above-mentioned embodiments, and improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should all fall within the protection scope of the present invention.

Claims (10)

1. The structure of the iron-lead single flow battery is characterized by comprising a negative electrode material layer, an ion selective permeation membrane and a positive electrode material layer which are sequentially arranged; the negative electrode material layer is filled with negative electrode electrolyte, the positive electrode material layer is filled with positive electrode electrolyte, and the positive electrode electrolyte circularly flows in the positive electrode material layer;

the negative electrode material layer comprises two or three components of a lead simple substance, a solid divalent lead salt and a conductive agent;

the negative electrode electrolyte is a mixed aqueous solution formed by inorganic acid and an additive;

the positive electrode material layer is a porous carbon electrode layer;

the positive electrolyte comprises a mixed aqueous solution formed by a ferric salt solution, a ferrous salt and an inorganic acid.

2. An iron-lead single flow battery structure as claimed in claim 1, wherein said solid divalent lead salt is one or a combination of lead sulfate and lead chloride;

the conductive agent is one or a combination of more of conductive carbon black, graphene, carbon powder, carbon nano tubes, carbon fibers and copper.

3. The structure of the iron-lead single flow battery according to claim 1, wherein the total mass of the elemental lead and the solid divalent lead salt in the negative electrode material layer is 20 to 100% of the mass of the electrode material layer.

4. The structure of claim 1, wherein the negative electrode material layer further comprises a binder.

5. The structure of the iron-lead single flow battery as claimed in claim 1, wherein the thickness of the negative electrode material layer is 0.5-20mm, the negative electrode material layer is a porous solid electrode, the pores are open pores, and the porosity is 10-80%.

6. The structure of the iron-lead single flow battery according to claim 1, wherein the porous carbon electrode layer is one or a combination of carbon felt, carbon paper, carbon cloth and a porous carbon plate;

the ferrous salt is one or the combination of two of ferrous sulfate and ferrous chloride, and the ferric salt is one or the combination of two of ferric sulfate and ferric chloride;

the inorganic acid is one or the combination of two of sulfuric acid or hydrochloric acid;

the ion selective membrane is one or more of ion exchange resin membrane, porous polymer membrane and swelling polymer membrane.

7. An iron-lead single flow battery, comprising the iron-lead single flow battery structure of any one of claims 1 to 6, further comprising a positive plate, a positive plate frame, a negative plate frame, and an end plate;

the negative plate is arranged on the outer side of the negative material layer, the positive plate is arranged on the outer side of the positive material layer, and end plates are respectively arranged on the outer sides of the negative plate and the positive plate;

a negative plate frame is arranged around the negative material layer, and a positive plate frame is arranged around the positive material layer;

and the anode plate frame is provided with a pipeline, and the other end of the pipeline is communicated with the anode electrolyte storage tank.

8. The iron-lead single flow battery as claimed in claim 7, wherein a circulation pump is provided on the pipe;

the positive plate and the negative plate are both prepared from metal or carbon materials;

a channel for supplementing cathode electrolyte and exhausting is arranged on the cathode plate frame;

current collecting plates are arranged between the positive plate and the end plate and between the negative plate and the end plate; the collector plate is made of metal or carbon material.

9. An iron-lead single flow battery stack, characterized in that it is composed of the iron-lead single flow battery structure of any one of claims 1 to 6 in series and/or parallel.

10. The iron-lead single flow battery stack of claim 9, wherein the iron-lead single flow battery structure, when formed in series, further comprises a positive plate, a positive plate frame, a negative plate frame, a bipolar plate, and an end plate;

bipolar plates are arranged among the iron-lead single flow battery structures, the negative plate is arranged on the outer side of the negative material layer on the outermost side, the positive plate is arranged on the outer side of the positive material layer on the outermost side, and end plates are respectively arranged on the outer sides of the negative plate and the positive plate; a negative plate frame is arranged around the negative material layer, and a positive plate frame is arranged around the positive material layer; the anode plate frame is provided with a pipeline, and the other end of the pipeline is communicated with the anode electrolyte storage tank;

when the iron-lead single flow battery structure is formed in a parallel connection mode, every two anodes share one cathode; the specific structural unit comprises a positive electrode material layer, an ion selective permeable membrane, a negative electrode material layer, an ion selective permeable membrane and a positive electrode material layer which are sequentially arranged; the positive plate and the end plate are sequentially arranged outside the positive material layers on the two sides; the negative plate, the channel that is used for replenishing negative pole electrolyte and exhaust are provided with respectively on the negative plate frame, be provided with the pipeline on the positive plate frame, the anodal electrolyte storage pot is communicate to the pipeline other end.

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