CN112993357A - Positive electrolyte of alkaline flow battery - Google Patents

Positive electrolyte of alkaline flow battery Download PDF

Info

Publication number
CN112993357A
CN112993357A CN201911277334.2A CN201911277334A CN112993357A CN 112993357 A CN112993357 A CN 112993357A CN 201911277334 A CN201911277334 A CN 201911277334A CN 112993357 A CN112993357 A CN 112993357A
Authority
CN
China
Prior art keywords
electrolyte
salt
cobalt
alkaline
positive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911277334.2A
Other languages
Chinese (zh)
Inventor
袁治章
李先锋
刘晓奇
张华民
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dalian Institute of Chemical Physics of CAS
Original Assignee
Dalian Institute of Chemical Physics of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dalian Institute of Chemical Physics of CAS filed Critical Dalian Institute of Chemical Physics of CAS
Priority to CN201911277334.2A priority Critical patent/CN112993357A/en
Publication of CN112993357A publication Critical patent/CN112993357A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/18—Regenerative fuel cells, e.g. redox flow batteries or secondary fuel cells
    • H01M8/184—Regeneration by electrochemical means
    • H01M8/188—Regeneration by electrochemical means by recharging of redox couples containing fluids; Redox flow type batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/8663—Selection of inactive substances as ingredients for catalytic active masses, e.g. binders, fillers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

The invention provides an alkaline flow battery anode electrolyte which is formed by cobalt salt, a complexing agent and strong alkali, cobalt ions are applied to an alkaline system for the first time after being complexed in a complexing mode, and the alkaline flow battery anode electrolyte can stably exist in an alkaline solution and has better activity and reversibility. An alkaline cobalt-based flow battery system is formed by pairing with a corresponding negative electrode pair. The alkaline cobalt-based flow battery has the characteristics of high battery efficiency and high energy density, and has a good application prospect in the field of energy storage.

Description

Positive electrolyte of alkaline flow battery
Technical Field
The invention relates to the field of flow batteries, in particular to an alkaline flow battery anode electrolyte.
Background
The flow battery is a new electrochemical energy storage technology, and compared with other energy storage technologies, the flow battery has the advantages of flexible system design, large storage capacity, free site selection, high energy conversion efficiency, deep discharge, safety, environmental protection, low maintenance cost and the like, and can be widely applied to the aspects of power generation and energy storage of renewable energy sources such as wind energy, solar energy and the like, emergency power supply systems, standby power stations, power systems and the like, and peak clipping and valley filling are realized. The full-vanadium redox flow battery (VFB) is considered to have a good application prospect due to the advantages of high safety, good stability, high efficiency, long service life (the service life is more than 15 years), low cost and the like, but the electrolyte solution of the VFB is expensive, so that the large-scale application of the VFB is limited to a certain extent. Therefore, the electrochemical energy storage battery with excellent development performance and low cost is very important for popularization and application of renewable energy sources.
Besides all vanadium flow batteries, the flow batteries developed at present mainly include zinc-bromine flow batteries, sodium polysulfide bromine and zinc-nickel battery systems. Among them, the zinc-bromine flow battery and the sodium polysulfide-bromine battery generate bromine during charging of the electrolyte at the positive electrode side to cause environmental pollution, and the large-scale application of the zinc-bromine flow battery and the sodium polysulfide-bromine battery is restricted. Various zinc-metal flow batteries exist, including zinc-nickel flow batteries (alkaline), alkaline zinc-iron flow batteries, and the like. For an alkaline zinc-nickel flow battery, the commercial sintered nickel surface capacity is limited, in the process of charging and discharging the battery, the nickel anode is subjected to a solid-solid phase reaction from nickel hydroxide to nickel oxyhydroxide, the oxygen evolution side reaction of the nickel anode is serious, the electric pair activity is low, and the operating working current density of the battery is low; in addition, 10-14 mol L of electrolyte of the zinc-nickel battery system is required-1The strong base of (2) as a supporting electrolyte, and such a high-concentration alkali solution is extremely corrosive to equipment. For an alkaline system, most metal ions cannot exist stably in an alkaline solution, and the metal ions and the alkali can generate precipitates, such as divalent and trivalent iron ions which are precipitated when being subjected to the alkali; divalent and trivalent cobalt ions are precipitated by alkali and cannot be used as active substances of the flow battery. Therefore, cobalt ions are generally used as a neutral or weakly acidic aqueous electrode pair or as an organic negative electrode pair (Energy) in the form of metallocene&Environmental Science,2017,10(2): 491-. Similar to the positive electrode iron couple of the alkaline zinc-iron flow battery, the stable ferricyanide is formed after complexing iron ions through cyanide, so that the stable ferricyanide can exist stably in alkali, but in a strong alkali solution, cyanide in the ferricyanide is easily replaced by hydroxide ions, so that the stability of the ferricyanide in the strong alkali solution is poor.
Disclosure of Invention
In order to solve the technical problems, the invention discloses an alkaline cobalt-based flow battery with high cycle stability, high energy density and battery performance.
The invention provides an alkaline flow battery anode electrolyte, which has the following specific technical scheme:
the flow battery positive electrolyte comprises a strong base A and an active substance, and a complex formed by a cobalt salt and a complexing agent is used as the active substance of the positive electrolyte; the cobalt salt is a divalent cobalt salt or a mixture of a divalent cobalt salt and a trivalent cobalt salt.
Based on the technical scheme, preferably, the divalent cobalt salt is CoF2，CoCl2，CoBr2，CoI2，CoO，Co(OH)2，CoCO3，Co(NO3)2，CoSO4One or two of them; the trivalent cobalt salt is CoF3，CoCl3，CoBr3，CoI3，Co2O3，Co(OH)3，Co2(CO3)3，Co2(NO3)3，Co2(SO4)3One or two of them; divalent cobalt salt is necessary, when the battery is charged for the first time, a divalent cobalt complex in the positive electrode electrolyte is oxidized into a trivalent cobalt complex, and the specific electrochemical reaction equation is as follows:
Figure BDA0002315910310000021
Figure BDA0002315910310000022
wherein the concentration of the active substance in the positive electrode electrolyte is 0.001-1.5 mol/L.
The complexing agent is one or more than two of xylitol, glucose, sodium gluconate, sorbitol and mannitol;
the positive electrode electrolyte can also comprise an auxiliary electrolyte A, and the concentration of the auxiliary electrolyte A in the positive electrode electrolyte is 0-30% of the concentration of strong base; the auxiliary electrolyte A is at least one of potassium chloride, sodium sulfate, sodium chloride and potassium sulfate; the strong base A is one or more than two of sodium hydroxide, potassium hydroxide or lithium hydroxide.
The invention also provides an alkaline cobalt-based flow battery, which comprises a battery module, a positive electrolyte storage tank, a negative electrolyte storage tank, a circulating pump and a circulating pipeline; the battery module is formed by connecting one or more than two single batteries in series/in parallel, each single battery comprises a positive current collecting plate, a negative current collecting plate, a positive electrode, a negative electrode and an ion conduction membrane, the negative electrolyte of the alkaline cobalt-based flow battery comprises strong base B and an active substance, and the active substance is Zn (OH)4 2-Or complex I, or a mixture of complex I and complex II, or an organic quinone; the complex I is a complex formed by a ferric salt and a complexing agent; the complex II is a complex formed by a ferrous salt and a complexing agent; in the mixture, the molar ratio of the ferrous salt to the ferric salt is more than 0 and less than 9; the positive electrolyte is the positive electrolyte; in the negative electrode electrolyte, the concentration of an active substance is 0.001-1.5 mol/L;
the ferric iron salt of the iron comprises one or more than two of ferric chloride, ferric bromide, ferric iodide, ferric sulfate, ferric nitrate, ferric carbonate and ferric oxalate;
the ferrous iron salt comprises one or more of ferrous chloride, ferrous bromide, ferrous iodide, ferrous sulfate, ferrous nitrate, ferrous carbonate and ferrous oxalate;
the complexing agent is one or more than two of xylitol, glucose, sodium gluconate, sorbitol and mannitol;
the negative electrode electrolyte can further comprise an auxiliary electrolyte B, and the concentration of the auxiliary electrolyte B is 0-30% of that of the strong base.
In the alkaline cobalt-based flow battery, a proper amount of quaternary ammonium salt, thiourea, polyvinyl alcohol and Bi can be added into the negative electrolyte3+、Ti+、Pd2+、Pb2+The dendrite formation inhibitor regulates and controls the deposition morphology of zinc, and the concentration range of the added dendrite formation inhibitor is 0-0.02 mol/L.
Based on the technical scheme, preferably, the ion-conducting membrane is a porous membrane or an ion-exchange membrane; the concentration of strong base in the positive electrolyte and the negative electrolyte in the aqueous solution is 0.001-10 mol/L; the concentration of active substances in the positive and negative electrode electrolytes is 0.001-1.5 mol/L; wherein the ion exchange membrane is one or more of a perfluorinated sulfonic acid ion exchange membrane, a partially fluorinated ion exchange membrane and a non-fluorinated ion exchange membrane.
The ion-conducting membrane may (or may not) be activated in a concentration of 0mol/L < aqueous base solution <10 mol/L.
Based on the technical scheme, preferably, the positive electrode and the negative electrode of the alkaline cobalt-based flow battery are independently selected from one of a metal flat plate electrode, a graphite plate flat plate electrode, a porous carbon felt, carbon paper or a carbon cloth electrode.
Based on the technical scheme, preferably, in the alkaline zinc-cobalt flow battery, the zinc oxide is zinc oxide, and the zinc salt is one or two of zinc chloride, zinc sulfate, zinc nitrate, zinc acetate, zinc bromide and zinc iodide;
based on the technical scheme, preferably, in the alkaline cobalt-based flow battery, the strong base A and the strong base B are independently one or more than two of sodium hydroxide, potassium hydroxide or lithium hydroxide.
In the alkaline cobalt-based flow battery, the anode current collecting plate and the cathode current collecting plate are graphite plates or copper plates.
The working current density of the alkaline cobalt-based flow battery is 1mA cm-2～160mA cm-2In the meantime.
The charge and discharge time of the alkaline cobalt-based flow battery can be controlled according to the concentration of the electrolyte and the volume of the electrolyte.
By screening the electrode and the ion-conducting membrane and optimizing the electrolyte composition, the assembled alkaline cobalt-based flow battery can be controlled at 1mA cm-2～160mA cm-2Between the working current densities of the meterAnd excellent battery performance is shown.
Beneficial results
1. The high-performance alkaline cobalt-based flow battery energy storage technology is developed, the reserves of zinc, iron and the like are abundant, the cost is low, and the high-performance alkaline cobalt-based flow battery energy storage technology has a good application prospect in the field of energy storage. The cobalt ions are applied to an alkaline system after being complexed through a complexing technology, can stably exist in an alkaline solution, and simultaneously keep the original activity and reversibility of the complexed cobalt ions, so that an electrochemical energy storage technology with low cost and excellent performance is developed.
2. Porous electrodes such as carbon felt, carbon paper, carbon cloth and the like can be activated in situ in alkaline electrolyte, the electrochemical performance of the porous electrodes is effectively improved, and in addition, a proper amount of quaternary ammonium salt, thiourea, polyvinyl alcohol and Bi are introduced into the negative electrode of the electrolyte3+、Ti+、Pd2+、Pb2+The additive can effectively solve the problem of short service life caused by zinc dendrite and zinc accumulation; the potential and the activity of the cobalt of the anode can be effectively regulated and controlled by changing the type of the complexing agent, and the battery shows excellent battery performance and has good application prospect in the field of energy storage.
3. The potential of the negative electrode couple can be regulated and controlled according to the concentration of alkali in the electrolyte and the type of the complexing agent, and a single cell assembled after being matched with the cobalt active substance in the positive electrode complexing state has higher open-circuit voltage, so that the single cell has higher power density.
4. The alkali-cobalt-based flow battery has the characteristics of high safety, good stability and simple structure and manufacturing process.
5. The concentration of positive and negative active materials can be improved by regulating and controlling the concentration of strong base of the supporting electrolyte and the kind of the complexing agent, so that the energy density of the battery is improved.
6. The invention discloses a biological polysaccharide complexing agent with stronger complexing ability, higher solubility and higher stability after complexing with metal ions; the assembled battery has higher energy density, cycling stability and battery efficiency.
Drawings
Fig. 1 is a schematic structural diagram of an alkaline zinc-cobalt flow battery of the invention.
Fig. 2 cyclic voltammetry tests of sorbitol complexed cobalt chloride/cobaltous chloride corresponding to examples 1 and 2, positive electrode active material composition: 0.2mol/L of [ Co (II) (A) OH]3-+0.2mol/L[Co(III)(A)OH]2-+3mol/L NaOH solution, wherein A is sorbitol complexing agent.
Fig. 3 shows cyclic voltammetry tests of negative electrode active materials according to examples 1 and 2, wherein the negative electrode active materials have the following compositions: 0.1mol/L Zn (OH)4 2-+3mol/L NaOH。
Fig. 4 is a schematic structural view of an aromatic ion-conducting membrane used in the present invention.
FIG. 5 shows the alkaline zinc-cobalt flow battery of example 1 at 40mA cm-2Current density of (a).
FIG. 6 alkaline Zinc-cobalt flow cell of example 2 at 120mA cm-2Current density of (a).
FIG. 7 alkaline Zinc-cobalt flow cell of example 3 at 80mA cm-2Current density of (a).
Detailed Description
Cyclic Voltammetry (CV) test of positive electrode active material: 0.2mol/L of [ Co (II) (A) OH]3-+0.2mol/L[Co(III)(A)OH]2-In +3mol/L NaOH, graphite plates were used as working electrodes (working electrode area: 1 cm)2) And a counter electrode, the Hg/HgO electrode being a reference electrode, at 10mV s-1The current and potential curves measured at sweep rate (FIG. 2) show the positive electrode couple [ Co (II) (A) OH-]3-/[Co(III)(A)OH]2-The electrochemical activity is better and the electrochemical reversibility is excellent.
Cyclic Voltammetry (CV) test of negative electrode active material: 0.1mol/L ZnO is dissolved in 3.2mol/L NaOH, and graphite plates are respectively used as working electrodes (working electrode area: 1 cm)2) And a counter electrode, the Hg/HgO electrode being a reference electrode, at 40mV s-1Curves of measured current and potential at sweep speed (fig. 3).
By Zn (OH)4 2-a/Zn pair and [ Co (II) (A) OH]3-/[Co(III)(A)OH]2-Cyclic voltammetry of couplesAnalysis of test results shows that the open-circuit voltage of the alkaline zinc-cobalt flow battery is about 1.37V, which is slightly higher than that (1.2V) of the most developed all-vanadium flow battery system at present.
Assembling single cells: the cells were assembled in the following order: positive electrode end plate, graphite current collector, positive electrode 6X 8cm2Carbon felt, ion conductive membrane (partial structural formula is shown in figure 4), and negative electrode of 6 x 8cm2Carbon felt, graphite current collector, negative pole end plate. The cell structure is shown in fig. 1.
Example 1
Sulfonated polyether ether ketone (SPEEK) is used as ion conducting membrane (structural formula shown in figure 4), and the positive electrolyte is 0.4mol/L [ Co (II) (A) OH)]3-+3mol/L OH-A solution; wherein the complexing agent is sorbitol; the negative electrode electrolyte is 0.2mol/L Zn (OH)4 2-+3mol/L OH-A solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 12min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). As can be seen from the battery cycle performance of FIG. 5, the CE, EE and VE distribution of the battery is maintained at about 98%, 89% and 91%, and the battery shows higher battery performance; within 17 cycles, the cell performance remained stable.
Example 2
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.4mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; wherein the complexing agent is sorbitol; the negative electrode electrolyte is 0.2mol/L Zn (OH)4 2-+3mol/L OH-A solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode, and the working current density of the battery is increased to 120mA cm-2At 120mA cm-2Under the condition of current density of (1), charging for 4min, and then cutting off the voltage to 120mA cm-2Is discharged to 0.8V under the current density condition of (2). As can be seen from the battery cycle performance of FIG. 6, the CE, EE and VE distribution of the battery is maintained at about 99%, 81% and 82%, and the battery shows higher battery performance; the battery performance remained stable within 80 cycles.
Example 3
SPEEK (structural formula shown in figure 4) is used as ion conductive membrane, and the positive electrolyte is 0.4mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; wherein the complexing agent is sorbitol; the negative electrode electrolyte is 0.2mol/L Zn (OH)4 2-+3mol/L OH-+0.01mol/L polyvinyl alcohol solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 12min, and then cutting off the voltage to obtain a voltage of 40mA cm-2The current density of the battery is discharged to 0.8V, the CE, EE and VE distribution of the battery is kept between 99 percent and 79 percent and about 80 percent, and the addition of polyvinyl alcohol can increase the polarization of a negative electrode due to the introduction of a polyvinyl alcohol additive into the negative electrolyte, so the voltage efficiency of the battery is reduced; but the introduction of the additive can obviously improve the deposition morphology of zinc, improve the cycling stability of the battery, and the battery can continuously and stably run for more than 140 cycles, so that the performance is basically kept stable.
Example 4
The SPEEK membranes were exchanged for Polybenzimidazole (PBI) ion conducting membranes and the cell test conditions were consistent with those of the alkaline zinc cobalt flow cell assembled with SPEEK membranes in example 1. As can be seen from the battery cycle performance of FIG. 7, the initial CE, EE and VE distributions of the battery are maintained at-99%, 89% and-90%, and higher battery performance is shown; however, as the cycle progresses, the efficiency of the cell tends to decline, and the specific reasons need to be further studied.
Example 5
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; wherein the complexing agent is sorbitol; the negative electrode electrolyte is 0.3mol/L Zn (OH)4 2-+3mol/L OH-A solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the performance of the battery, the CE, EE and VE distribution of the battery is maintainedAbout 98%, 88% and 90%, the battery shows higher battery performance; the battery continuously and stably runs for more than 200 cycles, and the performance is kept stable.
Example 6
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; the electrolyte of the negative electrode is 0.6mol/L [ Fe (III) (A) OH]2-+3mol/L OH-A solution; wherein the complexing agent is sodium gluconate; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the battery performance, the CE, EE and VE distribution of the battery is maintained at about 99 percent, 87 percent and 88 percent, and the battery has higher battery performance; the battery continuously and stably runs for more than 240 cycles, and the performance is kept stable.
Example 7
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-Solution in which the complexing agent sorbitol is replaced by sodium gluconate, i.e. [ Co (II) (A) OH]3-A in the formula (I) is sodium gluconate; the negative electrode electrolyte is 0.3mol/L Zn (OH)4 2-+3mol/L OH-A solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the battery performance, the CE, EE and VE distribution of the battery is maintained at about 99 percent, 84 percent and 85 percent, and the battery performance is lower than that when the sorbitol in the embodiment 4 is used as the complexing agent of the positive active material.
Example 8
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-Solution in which the complexing agent sorbitol is replaced by sodium gluconate, i.e. [ Co (II) (A) OH]3-A in the formula (I) is sodium gluconate; the negative electrode electrolyte is 0.3 mol-L Zn(OH)4 2-+3mol/L OH-A solution; adding 1mol/L potassium chloride (KCl) supporting electrolyte into the positive and negative electrolytes respectively to improve the conductivity of the positive and negative electrolytes, wherein the volumes of the positive and negative electrolytes are 60mL respectively; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the battery performance, the CE, EE and VE distribution of the battery is maintained at about 99 percent, 85 percent and 86 percent, which is slightly higher than the battery performance when no potassium chloride (KCl) supporting electrolyte is added into the electrolyte in the embodiment 5.
Comparative example 1
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; wherein, the complexing agent sorbitol is replaced by triethanolamine, and the cathode electrolyte is 0.3mol/L Zn (OH)4 2-+3mol/L OH-A solution; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the battery performance, the CE, EE and VE distribution of the battery is kept to 97 percent, 85 percent and 88 percent, and the battery shows higher battery performance; because the stability of the triethanolamine complexing agent in the alkaline solution containing the oxidant is poor, the cobalt ions complexed by the positive electrode are decomplexed in the alkaline solution, the bottom of an electrolyte storage tank is precipitated, the concentration of the active substance of the positive electrode is reduced, the utilization rate of the electrolyte of the battery is improved, the concentration polarization of the battery is increased in the final charging stage, the efficiency of the battery is gradually attenuated along with the circulation, the coulomb efficiency of the battery is attenuated to 93% from the initial 97% in less than 70 cycles, and the voltage efficiency is attenuated to 84% from the initial 88%.
Comparative example 2
SPEEK is used as ion conducting membrane, and the anode electrolyte is 0.6mol/L [ Co (II) (A) OH]3-+3mol/L OH-A solution; the electrolyte of the negative electrode is 0.6mol/L [ Fe (III) (A) OH]2-+3mol/L OH-A solution; wherein, the sodium gluconate complexing agents of the positive electrode and the negative electrode are changed into triethanolamine complexing agents; the volumes of the positive electrolyte and the negative electrolyte are respectively 60 mL; the battery adopts a constant current charge-discharge mode at 40mA cm-2Under the condition of current density of (1), charging for 20min, and then cutting off the voltage to obtain a voltage of 40mA cm-2Is discharged to 0.8V under the current density condition of (2). By testing the battery performance, the CE, EE and VE distribution of the battery is kept at about 96 percent, 83 percent and 86 percent, and the battery performance is lower than that of the battery in the embodiment 7; because the stability of the triethanolamine complexing agent in the alkaline solution containing the oxidant is poor, cobalt ions complexed by the positive electrode and iron ions complexed by the negative electrode are decomplexed in the alkaline solution, the bottom of an electrolyte storage tank is precipitated, the concentrations of active substances of the positive electrode and the negative electrode are reduced, the utilization rate of the electrolyte of the battery is improved, the concentration polarization of the battery is increased in the final charging stage, the efficiency of the battery is gradually attenuated along with the circulation, the coulomb efficiency of the battery is attenuated to 91% from the initial 96% in less than 50 cycles, and the voltage efficiency is attenuated to 80% from the initial 86%.

Claims (10)

1. The positive electrolyte of the alkaline flow battery is characterized in that a complex formed by cobalt salt and a complexing agent is used as an active substance of the positive electrolyte; the cobalt salt is a divalent cobalt salt or a mixture of a divalent cobalt salt and a trivalent cobalt salt.
2. The positive electrode electrolyte as claimed in claim 1, wherein the divalent cobalt salt is CoF2，CoCl2，CoBr2，CoI2，CoO，Co(OH)2，CoCO3，Co(NO3)2，CoSO4One or two of them; the trivalent cobalt salt is CoF3，CoCl3，CoBr3，CoI3，Co2O3，Co(OH)3，Co2(CO3)3，Co2(NO3)3，Co2(SO4)3One or two of them.
3. The positive electrode electrolyte solution according to claim 1, wherein the concentration of the active material in the positive electrode electrolyte solution is 0.001 to 1.5 mol/L.
4. The positive electrode electrolyte according to claim 1, characterized in that: the complexing agent is one or more than two of xylitol, glucose, sodium gluconate, sorbitol and mannitol.
5. The positive electrode electrolyte according to claim 1 or 2, characterized in that: the positive electrolyte also comprises strong base A and auxiliary electrolyte A; in the positive electrolyte, the ratio of the concentration of the auxiliary electrolyte A to the concentration of the strong base A is more than 0 and less than 0.3; the auxiliary electrolyte A is at least one of potassium chloride, sodium sulfate, sodium chloride and potassium sulfate; the strong base A is one or more than two of sodium hydroxide, potassium hydroxide or lithium hydroxide.
6. The alkaline cobalt-based flow battery comprises a battery module, a positive electrolyte storage tank, a negative electrolyte storage tank, a circulating pump and a circulating pipeline; the battery module is formed by connecting one or more than two single batteries in series/parallel, each single battery comprises a positive current collecting plate, a negative current collecting plate, a positive electrode, a negative electrode and an ion conducting membrane, and is characterized in that a negative electrolyte of the alkaline cobalt-based flow battery comprises strong base B and active substances; the active substance is Zn (OH)4 2-Or complex I, or a mixture of complex I and complex II, or an organic quinone; the complex I is a complex formed by a ferric salt and a complexing agent; the complex II is a complex formed by a ferrous salt and a complexing agent; in the mixture, the molar ratio of the ferrous salt to the ferric salt is more than 0 and less than 9; the negative electrode electrolyte is the positive electrode electrolyte according to any one of claims 1 to 5;
the ferric iron salt is one or more than two of ferric chloride, ferric bromide, ferric iodide, ferric sulfate, ferric nitrate, ferric carbonate and ferric oxalate;
the ferrous salt is one or more than two of ferrous chloride, ferrous bromide, ferrous iodide, ferrous sulfate, ferrous nitrate, ferrous carbonate and ferrous oxalate;
the complexing agent is one or more than two of xylitol, glucose, sodium gluconate, sorbitol and mannitol.
7. The alkaline cobalt-based flow battery according to claim 6, further comprising an auxiliary electrolyte B in the negative electrode electrolyte, wherein the ratio of the concentration of the auxiliary electrolyte B to the concentration of the strong base B is greater than 0 and less than 0.3; the auxiliary electrolyte B is at least one of potassium chloride, sodium sulfate, sodium chloride and potassium sulfate;
the negative electrode electrolyte also comprises an inhibitor; the inhibitor is quaternary ammonium salt, thiourea, polyvinyl alcohol and Bi3+Salt, Ti+Salt, Pd2+Salt, Pb2+Salt, the negative electrode electrolyte, and the inhibitor concentration (mol/L) is more than 0 and less than 0.02
The concentration of active substances in the negative electrode electrolyte is 0.001-1.5 mol/L;
the ion conducting membrane is a porous membrane or an ion exchange membrane, and the ion exchange membrane is one or more of a perfluorinated sulfonic acid ion exchange membrane, a partially fluorinated ion exchange membrane and a non-fluorinated ion exchange membrane.
8. The alkaline cobalt-based flow battery of claim 6, wherein the positive and negative electrodes are independently one of a metal plate electrode, a graphite plate electrode, a porous carbon felt, a carbon paper or a carbon cloth electrode.
9. The alkaline cobalt-based flow battery according to claim 7, wherein the strong base B is one or more of sodium hydroxide, potassium hydroxide, or lithium hydroxide.
10. The alkaline cobalt-based flow battery of claim 7, wherein: the positive current collecting plate and the negative current collecting plate are graphite plates or copper plates.
CN201911277334.2A 2019-12-12 2019-12-12 Positive electrolyte of alkaline flow battery Pending CN112993357A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911277334.2A CN112993357A (en) 2019-12-12 2019-12-12 Positive electrolyte of alkaline flow battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911277334.2A CN112993357A (en) 2019-12-12 2019-12-12 Positive electrolyte of alkaline flow battery

Publications (1)

Publication Number Publication Date
CN112993357A true CN112993357A (en) 2021-06-18

Family

ID=76332559

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911277334.2A Pending CN112993357A (en) 2019-12-12 2019-12-12 Positive electrolyte of alkaline flow battery

Country Status (1)

Country Link
CN (1) CN112993357A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114566654A (en) * 2022-03-01 2022-05-31 安徽理工大学 ZIF-derived Fe/Co-N-C electrocatalyst in shape of rich-edge round cake, preparation method and application thereof
CN114899466A (en) * 2022-06-21 2022-08-12 中山大学 Ferromanganese flow battery and manufacturing method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN85101242A (en) * 1984-02-04 1987-01-17 舍林股份公司 Be used for copper, nickel, cobalt and alloy thereof are carried out a kind of alkali lye bath and the technological process thereof of electroless plating
CN104854732A (en) * 2012-07-27 2015-08-19 洛克希德马丁尖端能量存储有限公司 Electrochemical energy storage systems and methods featuring large negative half-cell potentials
US20160204460A1 (en) * 2013-10-07 2016-07-14 Board Of Regents, The University Of Texas System A redox flow battery that uses complexes of cobalt and iron with amino-alcohol ligands in alkaline electrolytes to store electrical energy
CN108461784A (en) * 2016-12-10 2018-08-28 中国科学院大连化学物理研究所 A kind of Alkaline Zinc iron liquid galvanic battery

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN85101242A (en) * 1984-02-04 1987-01-17 舍林股份公司 Be used for copper, nickel, cobalt and alloy thereof are carried out a kind of alkali lye bath and the technological process thereof of electroless plating
CN104854732A (en) * 2012-07-27 2015-08-19 洛克希德马丁尖端能量存储有限公司 Electrochemical energy storage systems and methods featuring large negative half-cell potentials
US20160204460A1 (en) * 2013-10-07 2016-07-14 Board Of Regents, The University Of Texas System A redox flow battery that uses complexes of cobalt and iron with amino-alcohol ligands in alkaline electrolytes to store electrical energy
CN108461784A (en) * 2016-12-10 2018-08-28 中国科学院大连化学物理研究所 A kind of Alkaline Zinc iron liquid galvanic battery

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
胡佳萍: "宽电流密度焦磷酸盐镀铜的工艺及电沉积行为研究", 《中国优秀博硕士学位论文全文数据库（硕士）》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114566654A (en) * 2022-03-01 2022-05-31 安徽理工大学 ZIF-derived Fe/Co-N-C electrocatalyst in shape of rich-edge round cake, preparation method and application thereof
CN114899466A (en) * 2022-06-21 2022-08-12 中山大学 Ferromanganese flow battery and manufacturing method thereof

Similar Documents

Publication Publication Date Title
Zhang et al. Cost-effective iron-based aqueous redox flow batteries for large-scale energy storage application: A review
WO2018103517A1 (en) Alkaline zinc-iron flow battery
CN111244518B (en) Water system neutral organic flow battery
CN109509901B (en) Alkaline zinc-iron flow battery
CN112467179B (en) Alkaline all-iron flow battery
CN113764714A (en) Electrolyte of water system flow battery, all-iron water system flow battery and application
CN112993357A (en) Positive electrolyte of alkaline flow battery
Yuan et al. Perspective of alkaline zinc-based flow batteries
CN112952172B (en) Alkaline iron-nickel flow battery
CN103904352B (en) Zinc electrolyte for flow battery and preparation method thereof
CN111244516A (en) Application of additive in alkaline zinc-nickel flow battery negative electrolyte
CN112952212A (en) Aqueous manganese dioxide-metal secondary battery
CN110224157B (en) Non-circulating flow battery
WO2023082842A1 (en) Alkaline negative electrode electrolyte and alkaline zinc-iron flow battery assembled by same
CN104300169A (en) Alkaline zinc vanadium flow battery
US20240047714A1 (en) Rechargeable flow battery
CN113903963B (en) Neutral zinc-iron flow battery and application thereof
US11552324B2 (en) High efficiency zinc-iodine adsorption-aided flow battery with a low cost membrane
CN112952173B (en) Neutral zinc-iron flow battery with food-grade electrolyte
CN113826258A (en) Electrolytic cell for high voltage and scalable energy storage
CN110729505A (en) Iron-chromium flow battery electrolyte and application thereof
CN110071317A (en) A kind of tin bromine flow battery
CN111200146B (en) Negative electrode electrolyte for alkaline zinc-based flow battery and preparation and application thereof
CN113013460B (en) Negative electrolyte for alkaline zinc-iron flow battery and zinc-iron flow battery
CN116247262A (en) Alkaline zinc-manganese flow battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20210618

RJ01 Rejection of invention patent application after publication