CN111200153A - All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte - Google Patents

All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte Download PDF

Info

Publication number
CN111200153A
CN111200153A CN201811378607.8A CN201811378607A CN111200153A CN 111200153 A CN111200153 A CN 111200153A CN 201811378607 A CN201811378607 A CN 201811378607A CN 111200153 A CN111200153 A CN 111200153A
Authority
CN
China
Prior art keywords
electrolyte
less
equal
group
vanadium
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
CN201811378607.8A
Other languages
Chinese (zh)
Inventor
邹毅
高新亮
赵叶龙
王晓丽
陈彦博
宋玉波
杜新雨
王芳
王子
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 Rongke Power Co Ltd
Original Assignee
Dalian Rongke Power Co Ltd
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 Rongke Power Co Ltd filed Critical Dalian Rongke Power Co Ltd
Priority to CN201811378607.8A priority Critical patent/CN111200153A/en
Publication of CN111200153A publication Critical patent/CN111200153A/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
    • H01M2300/00—Electrolytes
    • H01M2300/0002—Aqueous electrolytes
    • H01M2300/0005—Acid electrolytes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0002—Aqueous electrolytes
    • H01M2300/0005—Acid electrolytes
    • H01M2300/0011—Sulfuric acid-based
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0088—Composites
    • H01M2300/0091—Composites in the form of mixtures
    • 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

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Fuel Cell (AREA)

Abstract

The invention belongs to the field of inhibiting precipitation of easily precipitated elements of electrolyte, and discloses a formula and a process of all-vanadium redox flow battery electrolyte for inhibiting precipitation of easily precipitated element impurities of the electrolyte. According to different precipitation characteristics and precipitation conditions of easily precipitated elements, the highest limit value of the easily precipitated elements which can be borne by electrodes in a vanadium electrolyte and a battery is comprehensively considered, and the easily precipitated elements are controlled according to the concentration upper limit value when a certain main group (or a sub group) exists simultaneously or singly, so that the concentration interval of the system for long-time safe operation is given. The invention can effectively control the content of easily precipitated elements, improve the stability of the electrolyte, prolong the service life of equipment such as battery resistance and the like, and effectively reduce the cost of the electrolyte.

Description

All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte
Technical Field
The invention belongs to the field of inhibiting precipitation of easily precipitated elements of electrolyte, and particularly relates to a formula and a process of all-vanadium redox flow battery electrolyte for inhibiting precipitation of easily precipitated element impurities of the electrolyte.
Background
In the existing quality standard of the electrolyte of the all-vanadium redox flow battery, the requirement on impurity metal ions in the electrolyte is single, namely the content of other elements except the main element vanadium (V) is kept in an extremely low range, but the quality standard of the electrolyte lacks the recognition and limit standard of easily precipitated elements. Part of element ions have the characteristics of easy hydrolysis, small solubility, co-ion precipitation and the like, when the element ions exist in the vanadium electrolyte, the element ions can be combined into insoluble simple substances, oxides or salts under certain conditions, and the insoluble substances are used as crystal nuclei to further promote precipitation of vanadium ions with valence of 4 and 5 and vanadium ions with valence of 2 and 3. After the sediment blocks the pipeline flow passage, the difference of the update speed of the anode solution and the cathode solution can cause the unbalance of the charge amount of the cathode electrolyte, so that the self-discharge of the battery system is aggravated, and the discharge capacity is gradually reduced.
Meanwhile, the control and detection modes of part of elements are deficient, the elements are often difficult to remove once entering the electrolyte, and the continuous accumulation characteristic of the elements causes great influence on the system capacity and efficiency, which is one of the main reasons that the flow of a plurality of vanadium battery systems is suddenly reduced, and the discharge capacity is rapidly reduced. From the practical application perspective, the allowable upper limit of the concentration of the elements in the electrolyte is not reported in relevant applications, and qualitative and quantitative descriptions are not provided; in addition, the existing all-vanadium electrolyte requires high purity (> 98%) of the raw material vanadium, and further causes the cost of the electrolyte to be high.
However, excessive limitation of the content of these elements directly increases the production cost of the electrolyte and the procurement cost of vanadium as raw material, for example, in some reports, if the content of elements such as Na, K, Al and the like is limited below 20mg/L, and if the content of elements such as Cu, Sb and the like is limited below 1mg/L, then the vanadium as raw material required for producing the electrolyte has to be used as raw material with purity of > 98%, so that the procurement cost of the raw material is increased by about 15% compared with the vanadium as raw material with purity of 97%.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides the electrolyte formula and the process of the all-vanadium redox flow battery for inhibiting the precipitation of the easily precipitated element impurities of the electrolyte, which can effectively control the content of the easily precipitated element, improve the stability of the electrolyte, prolong the service life of equipment such as battery resistance and the like, and effectively reduce the cost of the electrolyte.
The above purpose of the invention is realized by the following technical scheme:
the highest limit value of easily precipitated elements which can be borne by electrodes in the vanadium electrolyte and the battery is considered, the easily precipitated elements are controlled according to the upper limit value of the concentration of the easily precipitated elements when a certain main group (or a sub group) exists simultaneously or singly, and the concentration interval of the system for long-time safe operation is given.
The requirements for the electrolyte system are as follows:
sulfuric acid system electrolyte parameters: unless otherwise specified, the concentration of free sulfuric acid is more than 1mol/L and less than 4mol/L, and the concentration of vanadium ions is more than 1mol/L and less than 3 mol/L;
HCl system electrolyte parameters: unless otherwise specified, the concentration of free hydrochloric acid is more than 5mol/L and less than 11mol/L, and the concentration of vanadium ions is more than 2mol/L and less than 4 mol/L;
electrolyte parameters of the mixed acid system: unless otherwise specified, the concentration of free hydrochloric acid is 5mol/L or more and 11mol/L or less, the concentration of vanadium ions is 2mol/L or more and 4mol/L or less, and the concentration of free sulfuric acid is 0.1mol/L or more and 3mol/L or less;
limiting the content of hydrogen evolution elements in the raw material vanadium, wherein the content limit value is as follows: when the vanadium raw material containing the hydrogen evolution element is completely dissolved to form the electrolyte, the content of the hydrogen evolution ions of the vanadium raw material can meet the following requirements:
containing any one or more than one of the following sub-group elements 1) to 9), when each group element is present alone, it should satisfy:
the content unit of the listed elements is as follows: mg/L.m3/m2The specific meaning of the unit is as follows: ion concentration mg-L x amount of electrolyte m3Area of electrode m2(ii) a The specific content ranges are as follows:
1) main group IIA: comprises Be, Mg, Ca, Sr and Ba, wherein any element is less than or equal to 60, and Be + Mg + Ca + Sr + Ba is less than or equal to 300;
2) group IIIA: comprises B, Al and Ga, wherein any element is less than or equal to 100, and B + Al + Ga is less than or equal to 300;
3) main group IVA: comprises C, Si, Ge, Sn and Pb, wherein any element is less than or equal to 20, and C + Si + Ge + Sn + Pb is less than or equal to 100;
4) VIA main family: comprises S, Se and Te, wherein any element is less than or equal to 20, and S + Se + Te is less than or equal to 60;
5) group IIB: comprises Zn, Cd and Hg, wherein any element is less than or equal to 30, and Zn + Cd + Hg is less than or equal to 100;
6) subgroup IVB: comprises Ti and Zr, wherein any element is less than or equal to 80, and Ti + Zr is less than or equal to 160;
7) main group VA: comprises As, Sb and Bi, wherein any element is less than or equal to 10, and As + Sb + Bi is less than or equal to 30;
8) group IB: comprises Cu, Ag and Au, wherein any element is less than or equal to 10, and Cu + Ag + Au is less than or equal to 30;
9) group VIB: comprises W, Mo and Cr, wherein any one element of the W, the Mo and the Cr is 20, and the sum of W, the Mo and the Cr is less than or equal to 60;
the electrolyte is any one of the parameters of sulfuric acid system electrolyte and HCl system electrolyte and the mixed acid system electrolyte.
Further, when group IIA, group IIIA and group IVA elements are present simultaneously, the following requirements should be satisfied: be + Mg + Ca + Sr + Ba + B + Al + Ga + C + Si + Ge + Sn + Pb is less than or equal to 1000, and any element in the IIA group is less than or equal to 80, any element in the IIIA group is less than or equal to 150, and any element in the IVA group is less than or equal to 30;
further, when the elements of main group IIIA, IVB and VIB are present simultaneously, the following requirements should be met: b + Al + Ga + Ti + Zr + W + Mo + Cr is less than or equal to 700, any element in the IIIA main group is less than or equal to 100, any element in the IVB group is less than or equal to 120, and any element in the VIB group is less than or equal to 50;
further, when elements of group IIB, group VA and group IB are simultaneously present, the following requirements should be satisfied: zn + Cd + Hg + As + Sb + Bi + Cu + Ag + Au is less than or equal to 300, any element in the IIB group is less than or equal to 80, and any element in the VA main group is less than or equal to 10; any element in IB group is less than or equal to 10;
further, when the elements of main group IIA, IIB and VIA exist simultaneously, the following requirements should be satisfied: be + Mg + Ca + Sr + Ba + Zn + Cd + Hg + S + Se + Te is less than or equal to 700, and any element in IIA main group is less than or equal to 80, any element in VIA main group is less than or equal to 40, and any element in IIB main group is less than or equal to 50;
further, when the elements of main group IIA, IIIA and IVA are present simultaneously, the following requirements should be satisfied: be + Mg + Ca + Sr + Ba + B + Al + Ca + C + Si + Ge + Sn + Pb is less than or equal to 900, and any element in the IIA main group is less than or equal to 80, any element in the IVA main group is less than or equal to 30, and any element in the IIIA main group is less than or equal to 100;
the electrolyte is any one of the parameters of sulfuric acid system electrolyte and HCl system electrolyte and the mixed acid system electrolyte.
The specific operation is as follows: if 2mol/L vanadium electrolyte needs to be prepared, 95 percent of V is needed2O5187.63g of vanadium raw material, but when the raw material contained 1.62% sodium sulfate, the raw material was completely dissolved to form a vanadium electrolyte solution containing Na+1000mg/L, so if the electrolyte product Na is controlled+<1000mg/L, the raw material with the sodium sulfate content of less than 1.62 percent is selected.
The process control method of the invention is as shown in figure 1, the raw materials are adjusted and prepared according to the process control method, and vanadium electrolyte is prepared on the basis of the element content required by the formula;
the production process of the electrolyte is divided into the following two methods: calcination reduction and electrolysis, and chemical reduction and electrolysis.
(I) calcination reduction + electrolysis method
(1) According to the standard of the amplified element content in the technical scheme of the invention, the raw material of ammonium metavanadate with vanadium purity of 95% is selected.
(2) Adding ammonium metavanadate as raw material into a reaction furnace, and adding reducing substance (NH)3) Calcining at the high temperature of 500-900 ℃ for reduction reaction, wherein the product is vanadium (V) tetraoxide2O4) Powder, water, nitrogen, etc. and through cooling the reaction material inside the furnace to below 50 deg.c, the first washing and reaction of the reaction productFiltering to remove insoluble silt or washing off part of soluble salts (controlling the aperture of filter bag)<10 μm, so that insoluble substances in the process are hung in the filter bag);
(3)V2O4adding the powder into an acid-proof reaction kettle containing 10-15 wt% sulfuric acid or 20-25 wt% hydrochloric acid, mixing, heating, stirring, reacting for about 30 min, filtering for the second time to obtain VOSO containing 10 wt% sulfuric acid4Or VOCl with the hydrochloric acid concentration of 25-30 wt%2A vanadium oxychloride aqueous solution;
(4) the prepared electrolyte with the valence of 4 or more than 3.5 is pumped into a negative storage tank of an electrolysis system, and the electrolysis current (80 mA/cm) is set2) Carrying out electrolytic reduction to obtain a sulfuric acid or hydrochloric acid electrolyte finished product with a valence state of 3.5 (the vanadium ions with the valence of 3 and 4 respectively account for 50% of molar concentration).
The process of adding complexing agent or precipitant to remove impurity ions is omitted in the conventional process (because a certain amount of impurity ions are allowed to exist according to the process requirement).
(II) when the vanadium raw material is powdery V2O5The chemical reduction and electrolysis method is used, and the method comprises the following steps:
1) the raw material ammonium metavanadate is selected as the raw material with the vanadium purity of 95 percent according to the standard of amplified element content in the technical scheme of the invention.
2) According to the requirement of vanadium concentration in the finished product, the vanadium concentration is changed to V2O5Adding 10-15% sulfuric acid or 20-25% hydrochloric acid into the material, stirring to partially dissolve, and stirring for 60 min;
3) according to the ratio of 5-valent vanadium ion (VO)2 +) Is completely reduced into (VO)2+) The required amount of reducing agent is calculated and added with reducing agents such as oxalic acid, ethanol, saccharides and the like (SO can be directly introduced)2Gas), making the partially dissolved 5-valent vanadium ions (VO) in the step 1)2 +) Reduced to 4-valent vanadium ions (VO)2+) And finally promote V2O5All dissolve and reduce into 4-valent vanadium ions (VO)2+)；
4) Filtering to remove insoluble substances (such as silt), and reducingVanadium ion (VO) of valence 42+) Introducing the solution into a cathode storage tank of an electrolysis system for electrolytic reduction, and setting the electrolytic current density to be 80mA/cm according to the electrode area of the electrolysis system2Until the cathode electrolyte reaches 3.5 (the vanadium ions with 3 valence and 4 valence respectively account for 50% of molar concentration);
5) and filtering again (controlling the aperture of the filter bag to be less than 10 mu m, so that insoluble substances in the process are hung in the filter bag) to remove insoluble impurities (scraps, polymers and the like) in the solution to obtain a finished product of sulfuric acid or hydrochloric acid electrolyte.
The process of adding complexing agent or precipitator to remove impurities from impurity ions in the common process is omitted in the process (because a certain amount of impurity ions are allowed to exist according to the process requirement);
the electrolyte systems of the two methods are a sulfuric acid system and a hydrochloric acid system or a mixed acid system, wherein the sulfuric acid system is as follows: the concentration of free sulfuric acid is 1-4 mol/L, and the concentration of vanadium ions is 1-3 mol/L; hydrochloric acid system: the concentration of the free hydrochloric acid is 5-11 mol/L, and the concentration of vanadium ions is 2-4 mol/L; sulfuric acid and hydrochloric acid mixed system: the concentration of free hydrochloric acid is 5-11 mol/L, the concentration of free sulfuric acid is 0.1-3 mol/L, and the concentration of vanadium ions is 2-4 mol/L.
Compared with the prior art, the invention has the beneficial effects that:
1. reduced raw material and production costs
The excessive limitation of the content of the elements directly leads to the increase of the production cost of the electrolyte and the purchase cost of the vanadium raw material, and after the elements are released, the purchase cost of the vanadium raw material (the vanadium content is 96 percent) is reduced by about 10 percent compared with the vanadium raw material (the vanadium content has the purity of more than 98 percent) required by the prior art.
2. Interaction reduces the possibility of precipitation
In the invention, under the coexistence of other different group element ions, the influence of the precipitation of the easily precipitated element is weakened due to the interaction among the ions, and the precipitation time of the easily precipitated ion is prolonged when a plurality of ions coexist compared with the precipitation time when the ions exist independently, so that the upper limit of the concentration of the required ions for forming the precipitate in the electrolyte is improved, and finally, the maximum allowable amount of the easily precipitated metal ions in the raw material vanadium is widened, thereby reducing the precipitation.
3. The stability of the electrolyte is improved; the increase percentage of the internal resistance of the electrolyte galvanic pile is less than or equal to the increase percentage of the internal resistance of the electrolyte galvanic pile of a reference sample; under the operating condition of 45 ℃, the electrolyte of the invention has no precipitation phenomenon, and compared with the electrolyte, the precipitation phenomenon appears to block pipelines;
4. the invention allows certain easily deposited elements to exist in certain concentration, and can reduce the overall cost of the electrolyte on the basis of not influencing the performance of the solution and the battery material;
5. the content of easily precipitated elements can be effectively controlled, the stability of the electrolyte is improved, the service life of equipment such as battery resistance is prolonged, and the cost of the electrolyte is effectively reduced.
Drawings
FIG. 1 is a flow chart of the calcination reduction electrolysis process control of the present invention.
FIG. 2 is a graph comparing the operating voltage efficiency of the experimental electrolyte and the control sample in example 2 of the present invention.
Detailed Description
The invention is described in more detail below with reference to specific examples, without limiting the scope of the invention. Unless otherwise specified, the experimental methods adopted by the invention are all conventional methods, and experimental equipment, materials, reagents and the like used in the experimental method can be obtained from commercial sources.
Example 1
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000051
the data and the operation result show that the concentration of the above 9 types of easily-deposited elements is properly amplified and then H is adopted2SO4The system electrolyte, 2kW battery, experiences more than 190 charge-discharge cycles, and the experimental electrolyte system has no obvious change in system efficiency compared with the high-purity vanadium sample battery, which shows that the easily deposited elements are properly released, and the discharge capacity, efficiency and the like of the system in long-term charge-discharge operation are not affected.
Example 2
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000052
Figure BDA0001871352190000061
the above data and operating results show that H is used2SO4The system electrolyte, 2kW battery, experiences more than 190 charge-discharge cycles, and the experimental electrolyte obtained by properly amplifying the concentration of the above 9 types of easily-deposited elements maintains good efficiency compared with the electrolyte battery of a sample with higher concentration of the contrast deposited elements, has no obvious change in flow, obviously increases the system internal resistance of the contrast electrolyte, and shows that the easily-deposited elements are excessively released, and the discharge capacity and efficiency of the system are seriously influenced by long-term charge-discharge operation.
Example 3
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000062
the data and the operation results show that the concentration of the easily deposited elements in the 3 groups is properly amplified and then H is adopted2SO4The system electrolyte, 10kW battery, experiences more than 190 charge-discharge cycles, and the experimental electrolyte system has 6 points higher system efficiency (figure 2) than the control sample battery, which indicates that the easily deposited elements are excessively released, and the system has serious influence on the discharge capacity, efficiency and the like during long-term charge-discharge operation.
Example 4
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000063
Figure BDA0001871352190000071
the data and the operation results show that the concentration of the easily deposited elements in the 3 groups is properly amplified and then H is adopted2SO4The system electrolyte, 10kW battery, experiences more than 190 charge-discharge cycles, and the experimental electrolyte system is 6 percentage points lower than the system internal resistance of the control sample battery, which indicates that the easily deposited elements are excessively released, and the influence on the discharge capacity, efficiency and the like of the system in long-term charge-discharge operation is serious.
Example 5
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000072
the data and the operation results show that after the concentration of the easily-deposited elements in the 3 groups is properly amplified, the HCl system electrolyte and the 30kW battery are adopted, more than 190 charge-discharge cycles are carried out, and compared with a control sample battery, the experimental electrolyte system has the advantages that the system internal resistance is lower by 4.5 percent, and the voltage efficiency is higher by 4 percent. The method shows that the easily deposited elements are properly controlled, and the discharge capacity, the efficiency and the like of the system in long-term charge-discharge operation are not influenced.
Example 6
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000081
the data and the operation results show that the concentration of the easily deposited elements in the 3 groups is properly amplified and then H is adopted2SO4The system electrolyte, 30kW battery, undergoes more than 190 charge-discharge cycles, and compared with the control sample battery, the experimental electrolyte system has both system internal resistance and voltage efficiencyElectrolyte solution due to control sample. The method shows that the easily deposited elements are properly controlled, and the discharge capacity, the efficiency and the like of the system in long-term charge-discharge operation are well maintained.
Example 7
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000082
the above data and operating results show that, properly scaling up the concentration of the group 3 easily depositable element above, the concentration limit of the element is reduced due to interaction. Experiment adopted H2SO4The system electrolyte, 30kW battery, experiences more than 190 charge-discharge cycles, and the experimental electrolyte system is inferior to the experimental electrolyte in both internal resistance and voltage efficiency compared with the control sample battery. The method shows that the easily deposited elements are excessively amplified, and the influence on the discharge capacity, the efficiency and the like of the system in long-term charge-discharge operation is serious.
Example 8
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000091
the above data and operating results show that, properly scaling up the concentration of the group 3 easily depositable element above, the concentration limit of the element is reduced due to interaction. The experiment adopts HCl system electrolyte, 10kW battery, experiences more than 190 charge-discharge cycles, and the internal resistance and voltage efficiency of the control experiment system are inferior to those of the experiment electrolyte compared with the control sample battery. The method shows that the easily deposited elements are excessively amplified, and the influence on the discharge capacity, the efficiency and the like of the system in long-term charge-discharge operation is serious.
Example 9
Vanadium electrolytes were prepared and run according to the contents of the experimental and control samples in the following table, with the results shown in the following table:
Figure BDA0001871352190000092
the above data and operating results show that the concentrations of the above group 3 easily depositable elements are properly amplified. The experiment adopts mixed acid system electrolyte, and a 30kW battery undergoes more than 190 charge-discharge cycles, and compared with a control high-purity vanadium sample battery, the experiment electrolyte system has no obvious difference in system internal resistance and voltage efficiency. The method shows that the easily deposited elements are properly amplified, and the discharge capacity, the efficiency and the like of the system in long-term charge-discharge operation are not influenced.
During continuous experiments, the content of the elements is properly released to a certain range, so that the system is ensured not to precipitate, the purchasing difficulty is reduced on the basis of not influencing the performance of the battery, the purity of the raw material is reduced to about 96% from more than 98%, and the cost of the raw material is reduced by 10%.
Experiments also find that if the easily precipitated elements coexist in other element ions, the precipitation influence of some easily precipitated elements is weakened due to the interaction among the ions, the precipitation possibility of the independently existing element ions is reduced due to the existence of multiple ions, the upper limit of the concentration of the required ions for forming precipitates in the electrolyte is improved, and the maximum allowable amount of the easily precipitated metal ions in the final raw material vanadium is widened.
Further, the pore size of the large filter bag is controlled, so that substances which are easy to deposit in the electrolyte of the system can be deposited in the filter bags of the positive electrode and the negative electrode of the system, the influence of the substances on the pipelines and the battery of the system can be greatly reduced, and the content of the elements which are easy to deposit can be further widened.
Compared with the prior art, the invention
1. Reduced raw material and production costs
Over-limiting the content of these elements will directly lead to an increase in the electrolyte production cost and in the raw material vanadium procurement cost:
the specific results are as follows:
Figure BDA0001871352190000101
data in the table, the average conversion is mg/L calculation
After the elements are released, the cost of the raw materials (vanadium content is 96%) needed to be purchased is reduced by about 15% compared with the vanadium (vanadium content purity is more than 98%) needed in the patent CN 105283996A.
2. Interaction reduces the possibility of precipitation
The upper limit of the element content is shown in the following table
Figure BDA0001871352190000102
Figure BDA0001871352190000111
Data in the table are converted into mg/L
In the invention, under the coexistence of other different group element ions, the influence of the precipitation of the easily precipitated element is weakened due to the interaction among the ions, and the precipitation time of the easily precipitated ion is prolonged when a plurality of ions coexist compared with the precipitation time when the ions exist independently, so that the upper limit of the concentration of the required ions for forming the precipitate in the electrolyte is improved, and finally, the maximum allowable amount of the easily precipitated metal ions in the raw material vanadium is widened, thereby reducing the precipitation.
3. The stability of the electrolyte is improved;
the specific results are as follows:
Figure BDA0001871352190000112
the increase percentage of the internal resistance of the electrolyte galvanic pile is less than or equal to the increase percentage of the internal resistance of the electrolyte galvanic pile of a reference sample; under the operating condition of 45 ℃, the electrolyte of the invention has no precipitation phenomenon, and compared with the electrolyte, the electrolyte has precipitation to block pipelines.
The embodiments described above are merely preferred embodiments of the invention, rather than all possible embodiments of the invention. Any obvious modifications to the above would be obvious to those of ordinary skill in the art, but would not bring the invention so modified beyond the spirit and scope of the present invention.

Claims (10)

1. The formula of the all-vanadium redox flow battery electrolyte for inhibiting the precipitation of the easily precipitated element impurities of the electrolyte is characterized in that the content of the hydrogen evolution element in the raw material vanadium is limited, and the content limit value is as follows: when the vanadium raw material containing the hydrogen evolution element is completely dissolved to form the electrolyte, the content of the hydrogen evolution ions of the vanadium raw material can meet the following requirements:
containing any one or more than one of the following elements of subgroups 1) to 9), which, when present alone, satisfies:
1) main group IIA: comprises Be, Mg, Ca, Sr and Ba, wherein any element is less than or equal to 60, and Be + Mg + Ca + Sr + Ba is less than or equal to 300;
2) group IIIA: comprises B, Al and Ga, wherein any element is less than or equal to 100, and B + Al + Ga is less than or equal to 300;
3) main group IVA: comprises C, Si, Ge, Sn and Pb, wherein any element is less than or equal to 20, and C + Si + Ge + Sn + Pb is less than or equal to 100;
4) VIA main family: comprises S, Se and Te, wherein any element is less than or equal to 20, and S + Se + Te is less than or equal to 60;
5) group IIB: comprises Zn, Cd and Hg, wherein any element is less than or equal to 30, and Zn + Cd + Hg is less than or equal to 100;
6) subgroup IVB: comprises Ti and Zr, wherein any element is less than or equal to 80, and Ti + Zr is less than or equal to 160;
7) main group VA: comprises As, Sb and Bi, wherein any element is less than or equal to 10, and As + Sb + Bi is less than or equal to 30;
8) group IB: comprises Cu, Ag and Au, wherein any element is less than or equal to 10, and Cu + Ag + Au is less than or equal to 30;
9) group VIB: comprises W, Mo and Cr, wherein any one element of the W, the Mo and the Cr is 20, and the sum of W, the Mo and the Cr is less than or equal to 60;
the content unit of the elements listed is as follows: mg/L.m3/m2The specific meaning of the unit is as follows: ion concentration mg/L.times.electrolyte volume m3Area of electrode m2；
The electrolyte is any one of the parameters of sulfuric acid system electrolyte and HCl system electrolyte and the mixed acid system electrolyte.
2. The electrolyte formula of the all-vanadium flow battery for inhibiting the impurity precipitation of the easily precipitated elements in the electrolyte according to claim 1, wherein the easily precipitated elements are controlled according to the upper concentration limit when a main group or a sub group exists simultaneously and a single easily precipitated element exists, so that a concentration interval for long-time safe operation of a system is given; the electrolyte system requires the following:
(1) sulfuric acid system electrolyte parameters: the concentration of free sulfuric acid is more than 1mol/L and less than 4mol/L, and the concentration of vanadium ions is more than 1mol/L and less than 3 mol/L;
(2) HCl system electrolyte parameters: the concentration of free hydrochloric acid is more than 5mol/L and less than 11mol/L, and the concentration of vanadium ions is more than 2mol/L and less than 4 mol/L;
(3) electrolyte parameters of the mixed acid system: the concentration of free hydrochloric acid is more than 5mol/L and less than 11mol/L, the concentration of vanadium ions is more than 2mol/L and less than 4mol/L, and the concentration of free sulfuric acid is more than 0.1mol/L and less than 3 mol/L.
3. The electrolyte formula of the all-vanadium flow battery for inhibiting the impurities of the easily precipitated elements in the electrolyte from being separated out according to claim 1, wherein when the elements in the IIA group, the IIIA group and the IVA group exist simultaneously, the following requirements are met: be + Mg + Ca + Sr + Ba + B + Al + Ga + C + Si + Ge + Sn + Pb is less than or equal to 1000, and any element in IIA group is less than or equal to 80, any element in IIIA group is less than or equal to 150, any element in IVA group is less than or equal to 30, the content unit of the elements listed is as follows: mg/L.m3/m2The specific meaning of the unit is as follows: ion concentration mg/L.times.electrolyte volume m3Area of electrode m2。
4. The electrolyte formula of the all-vanadium flow battery for inhibiting the impurity precipitation of the easily precipitated elements of the electrolyte according to claim 1, which is characterized in that when the elements of the IIIA main group, the IVB main group and the VIB main group exist simultaneously, the following requirements are met: b + Al + Ga + Ti + Zr + W + Mo + Cr is less than or equal to 700, any element in the IIIA main group is less than or equal to 100, any element in the IVB group is less than or equal to 120, any element in the VIB group is less than or equal to 50, and the content unit of the elements is as follows: mg/L.m3/m2Unit ofThe specific meanings are as follows: ion concentration mg/L.times.electrolyte volume m3Area of electrode m2。
5. The electrolyte formulation of the all-vanadium flow battery for inhibiting the precipitation of impurities in easily precipitated elements of the electrolyte according to claim 1, wherein the elements of group IIB, group VA and group IB are simultaneously present, and the following requirements are met: zn + Cd + Hg + As + Sb + Bi + Cu + Ag + Au is less than or equal to 300, any element in the IIB group is less than or equal to 80, and any element in the VA main group is less than or equal to 10; any element in IB group is less than or equal to 10, and the content unit of the listed elements is as follows: mg/L.m3/m2The specific meaning of the unit is as follows: ion concentration mg/L.times.electrolyte volume m3Area of electrode m2。
6. The electrolyte formulation of the all-vanadium flow battery for inhibiting the impurity precipitation of easily precipitated elements in the electrolyte according to claim 1, wherein the elements of main group IIA, main group IIB and main group VIA are present simultaneously, and the following requirements are met: be + Mg + Ca + Sr + Ba + Zn + Cd + Hg + S + Se + Te is less than or equal to 700, any element in IIA main group is less than or equal to 80, any element in VIA main group is less than or equal to 40, any element in IIB main group is less than or equal to 50, and the content units of the elements are as follows: mg/L.m3/m2The specific meaning of the unit is as follows: ion concentration mg/L.times.electrolyte volume m3Area of electrode m2。
7. The electrolyte formula of the all-vanadium flow battery for inhibiting the impurity precipitation of the easily precipitated elements in the electrolyte according to claim 1, wherein when the elements of the main group IIA, the main group IIIA and the main group IVA exist simultaneously, the following requirements are met: be + Mg + Ca + Sr + Ba + B + Al + Ca + C + Si + Ge + Sn + Pb is less than or equal to 900, and any element in the IIA main group is less than or equal to 80, any element in the IVA main group is less than or equal to 30, and any element in the IIIA main group is less than or equal to 100.
8. The process for preparing the electrolyte of the all-vanadium redox flow battery according to the formula of claim 1, wherein the preparation process adopts any one of a calcination reduction + electrolysis method and a chemical reduction + electrolysis method.
9. The process as claimed in claim 8, wherein the calcination reduction + electrolysis method comprises the following steps:
1) selecting raw materials with the vanadium purity of 95 percent;
2) adding raw material ammonium metavanadate into a reaction furnace, and adding a reducing substance NH3Calcining at the high temperature of 500 ℃ and 900 ℃ to carry out reduction reaction, wherein the product is V2O4Powder, water and nitrogen, cooling the reaction materials in the furnace to below 50 ℃, washing and filtering the reaction products for the first time, and filtering out insoluble silt or washing off part of soluble salts;
3)V2O4adding the powder into an acid-proof reaction kettle containing 10-15 wt% sulfuric acid or 20-25 wt% hydrochloric acid, mixing, heating, stirring, reacting for about 30 min, filtering for the second time to obtain VOSO containing 10 wt% sulfuric acid4Or VOCl with the hydrochloric acid concentration of 25-30 wt%2A vanadium oxychloride aqueous solution;
4) the prepared electrolyte with the valence of 4 or more than 3.5 is pumped into a negative storage tank of an electrolysis system, and the electrolysis current is set to be 80mA/cm2Carrying out electrolytic reduction to obtain a finished product of sulfuric acid or hydrochloric acid electrolyte with the valence state of 3.5.
10. The process as claimed in claim 8, wherein the chemical reduction + electrolysis method comprises the following steps:
when the vanadium raw material is powdery V2O5When the temperature of the water is higher than the set temperature,
1) selecting raw materials with the vanadium purity of 95 percent;
2) according to the requirement of vanadium concentration in the finished product, the vanadium concentration is changed to V2O5Adding 10-15 wt% sulfuric acid or 20-25 wt% hydrochloric acid into the material, stirring to dissolve part of the material, and stirring for 60 min;
3) according to the VO2 +Complete reduction to VO2+The required dosage of the reducing agent is calculated, and the reducing agent is added to ensure that the VO is partially dissolved in the step 1)2 +Reducing and finally promoting V2O5All dissolved and reduced to VO2+；
4) Filtering to remove insoluble substances, and reducing to VO2+Introducing the solution into a cathode storage tank of an electrolysis system for electrolytic reduction, and setting the electrolytic current density to be 80mA/cm according to the electrode area of the electrolysis system2Until the cathode electrolyte reaches 3.5 price;
5) and filtering again to remove insoluble impurities in the solution to obtain a finished product of sulfuric acid or hydrochloric acid electrolyte.
CN201811378607.8A 2018-11-19 2018-11-19 All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte Pending CN111200153A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811378607.8A CN111200153A (en) 2018-11-19 2018-11-19 All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811378607.8A CN111200153A (en) 2018-11-19 2018-11-19 All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte

Publications (1)

Publication Number Publication Date
CN111200153A true CN111200153A (en) 2020-05-26

Family

ID=70746016

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811378607.8A Pending CN111200153A (en) 2018-11-19 2018-11-19 All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte

Country Status (1)

Country Link
CN (1) CN111200153A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112941539A (en) * 2021-01-28 2021-06-11 湖南钒谷新能源技术有限公司 Vanadium electrolyte production method and production system
CN114275811A (en) * 2021-12-23 2022-04-05 大连博融新材料有限公司 Method for preparing electrolyte by purifying crude vanadium compound and electrolyte

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102341946A (en) * 2010-03-12 2012-02-01 住友电气工业株式会社 Redox flow battery
CN102842730A (en) * 2012-09-27 2012-12-26 北京金能世纪科技有限公司 All-vanadium flow battery
CN104037439A (en) * 2013-03-05 2014-09-10 中国人民解放军63971部队 Combined chemical-electrochemical method for preparing vanadium redox flow battery electrolyte
CN104638300A (en) * 2013-11-08 2015-05-20 苏州宝时得电动工具有限公司 Battery
CN105283996A (en) * 2013-06-21 2016-01-27 住友电气工业株式会社 Redox flow battery electrolyte and redox flow battery
CN105684203A (en) * 2013-09-25 2016-06-15 洛克希德马丁尖端能量存储有限公司 Electrolyte balancing strategies for flow batteries
KR20160091154A (en) * 2015-01-23 2016-08-02 순천대학교 산학협력단 Vanadium Redox flow battery comprising sulfonated polyetheretherketone membrane
CN106257725A (en) * 2016-01-28 2016-12-28 中国科学院过程工程研究所 A kind of system and method preparing high activity all-vanadium flow battery specific valence state electrolyte
CN106941186A (en) * 2017-03-21 2017-07-11 河钢股份有限公司承德分公司 A kind of V electrolyte and preparation method thereof
CN108808052A (en) * 2018-05-31 2018-11-13 四川星明能源环保科技有限公司 A kind of all vanadium ion redox flow battery electrolyte and preparation method thereof

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102341946A (en) * 2010-03-12 2012-02-01 住友电气工业株式会社 Redox flow battery
CN102842730A (en) * 2012-09-27 2012-12-26 北京金能世纪科技有限公司 All-vanadium flow battery
CN104037439A (en) * 2013-03-05 2014-09-10 中国人民解放军63971部队 Combined chemical-electrochemical method for preparing vanadium redox flow battery electrolyte
CN105283996A (en) * 2013-06-21 2016-01-27 住友电气工业株式会社 Redox flow battery electrolyte and redox flow battery
CN105684203A (en) * 2013-09-25 2016-06-15 洛克希德马丁尖端能量存储有限公司 Electrolyte balancing strategies for flow batteries
CN104638300A (en) * 2013-11-08 2015-05-20 苏州宝时得电动工具有限公司 Battery
KR20160091154A (en) * 2015-01-23 2016-08-02 순천대학교 산학협력단 Vanadium Redox flow battery comprising sulfonated polyetheretherketone membrane
CN106257725A (en) * 2016-01-28 2016-12-28 中国科学院过程工程研究所 A kind of system and method preparing high activity all-vanadium flow battery specific valence state electrolyte
CN106941186A (en) * 2017-03-21 2017-07-11 河钢股份有限公司承德分公司 A kind of V electrolyte and preparation method thereof
CN108808052A (en) * 2018-05-31 2018-11-13 四川星明能源环保科技有限公司 A kind of all vanadium ion redox flow battery electrolyte and preparation method thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
LIUYUE CAO ETAL: "A review of electrolyte additives and impurities in vanadium redox flow batteries", 《JOURNAL OF ENERGY CHEMISTRY》 *
陈孝娥 等: "V(Ⅲ)-V(Ⅳ)电解液的化学合成及性能", 《化工进展》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112941539A (en) * 2021-01-28 2021-06-11 湖南钒谷新能源技术有限公司 Vanadium electrolyte production method and production system
CN112941539B (en) * 2021-01-28 2023-06-23 湖南钒谷新能源技术有限公司 Vanadium electrolyte production method and production system
CN114275811A (en) * 2021-12-23 2022-04-05 大连博融新材料有限公司 Method for preparing electrolyte by purifying crude vanadium compound and electrolyte

Similar Documents

Publication Publication Date Title
CN109994716B (en) Coated high-nickel ternary precursor and preparation method thereof
CN102460812B (en) Preparation of flow cell battery electrolytes from raw materials
CN105283996B (en) Redox flow battery electrolytic solution and redox flow batteries
CN103526021B (en) A kind of zinc abstraction purification of leaching liquor is except cobalt method and scavenging agent used thereof
CN110190241B (en) A kind of preparation method of nickel cobalt manganese granular precursor
CN105378997B (en) Redox flow battery electrolytic solution and redox flow batteries
CN101269807A (en) High-density spherical iron phosphate and manufacture method thereof
CN111200153A (en) All-vanadium redox flow battery electrolyte formula and process for inhibiting precipitation of easily precipitated element impurities of electrolyte
JP2736498B2 (en) Method for producing indium oxide-tin oxide powder
CN113072048A (en) Sewage treatment and slag recycling process for producing iron phosphate by sodium method
CN110247039A (en) A kind of nickel lithium manganate cathode material preparation method coating strontium titanate base conductive coating
CN108054413B (en) Preparation method of high-energy 3.5-valent sulfur-salt mixed acid system vanadium electrolyte
CN113659129A (en) Multi-element doped ternary precursor and preparation method thereof
KR20020010144A (en) Method for Producing Nickel Hydroxides
CN113380999A (en) Preparation method of silver-iron oxide porous nanocube negative electrode material for molten salt battery
CN106684421B (en) Method for preparing vanadium electrolyte
CN108529666A (en) Method, product and the application of lithium titanate are prepared by inorganic ti sources
CN103173786B (en) A kind of environment-friendly high-efficiency produces the method for electrolytic metal Mn
CN116259811B (en) Method for preparing vanadium electrolyte from sodium vanadate solution
CN111200149A (en) Formula and process of electrolyte for all-vanadium redox flow battery
CN116960425A (en) Preparation method of iron-chromium flow battery electrolyte
CN111200150B (en) All-vanadium redox flow battery electrolyte formula and process for maintaining high performance of electrolyte
EP3845493A1 (en) Titanyl sulfate hydrate powder, method for producing titanyl sulfate hydrate powder, method for producing aqueous titanyl sulfate solution, method of producing electrolyte solution, and method for producing redox flow battery
CN111200147A (en) All-vanadium redox flow battery electrolyte for inhibiting hydrogen evolution of electrolyte and preparation method thereof
US2099658A (en) Preparation of chromic acid and sparingly soluble chromates

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20200526