CN117092089A - Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte - Google Patents
Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte Download PDFInfo
- Publication number
- CN117092089A CN117092089A CN202210522827.3A CN202210522827A CN117092089A CN 117092089 A CN117092089 A CN 117092089A CN 202210522827 A CN202210522827 A CN 202210522827A CN 117092089 A CN117092089 A CN 117092089A
- Authority
- CN
- China
- Prior art keywords
- lithium
- solution
- lithium battery
- borate
- battery electrolyte
- 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
Links
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 189
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 189
- 239000003792 electrolyte Substances 0.000 title claims abstract description 132
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 title claims abstract description 49
- 239000000243 solution Substances 0.000 claims abstract description 69
- 239000012086 standard solution Substances 0.000 claims abstract description 61
- 239000011159 matrix material Substances 0.000 claims abstract description 30
- 238000000034 method Methods 0.000 claims abstract description 25
- 150000001450 anions Chemical class 0.000 claims abstract description 19
- 239000012452 mother liquor Substances 0.000 claims abstract description 11
- XINQFOMFQFGGCQ-UHFFFAOYSA-L (2-dodecoxy-2-oxoethyl)-[6-[(2-dodecoxy-2-oxoethyl)-dimethylazaniumyl]hexyl]-dimethylazanium;dichloride Chemical compound [Cl-].[Cl-].CCCCCCCCCCCCOC(=O)C[N+](C)(C)CCCCCC[N+](C)(C)CC(=O)OCCCCCCCCCCCC XINQFOMFQFGGCQ-UHFFFAOYSA-L 0.000 claims abstract description 9
- 238000002360 preparation method Methods 0.000 claims abstract description 7
- 238000004587 chromatography analysis Methods 0.000 claims abstract description 5
- 238000009616 inductively coupled plasma Methods 0.000 claims description 30
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 27
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 25
- 238000007865 diluting Methods 0.000 claims description 17
- 239000012895 dilution Substances 0.000 claims description 17
- 238000010790 dilution Methods 0.000 claims description 17
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 10
- 238000005259 measurement Methods 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 7
- 150000002500 ions Chemical class 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 7
- 239000010413 mother solution Substances 0.000 claims description 7
- 238000012360 testing method Methods 0.000 claims description 7
- DEUISMFZZMAAOJ-UHFFFAOYSA-N lithium dihydrogen borate oxalic acid Chemical compound B([O-])(O)O.C(C(=O)O)(=O)O.C(C(=O)O)(=O)O.[Li+] DEUISMFZZMAAOJ-UHFFFAOYSA-N 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 239000003153 chemical reaction reagent Substances 0.000 claims description 5
- WXNUAYPPBQAQLR-UHFFFAOYSA-N B([O-])(F)F.[Li+] Chemical compound B([O-])(F)F.[Li+] WXNUAYPPBQAQLR-UHFFFAOYSA-N 0.000 claims description 4
- 238000012937 correction Methods 0.000 claims description 4
- PBCJIPOGFJYBJE-UHFFFAOYSA-N acetonitrile;hydrate Chemical compound O.CC#N PBCJIPOGFJYBJE-UHFFFAOYSA-N 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 239000003480 eluent Substances 0.000 claims description 3
- 229910052573 porcelain Inorganic materials 0.000 claims description 3
- NDZWKTKXYOWZML-UHFFFAOYSA-N trilithium;difluoro oxalate;borate Chemical compound [Li+].[Li+].[Li+].[O-]B([O-])[O-].FOC(=O)C(=O)OF NDZWKTKXYOWZML-UHFFFAOYSA-N 0.000 claims description 3
- 230000001172 regenerating effect Effects 0.000 claims description 2
- 230000008878 coupling Effects 0.000 abstract description 2
- 238000010168 coupling process Methods 0.000 abstract description 2
- 238000005859 coupling reaction Methods 0.000 abstract description 2
- 230000001939 inductive effect Effects 0.000 abstract description 2
- 229910013188 LiBOB Inorganic materials 0.000 description 18
- 239000000523 sample Substances 0.000 description 18
- 238000002474 experimental method Methods 0.000 description 14
- 238000001514 detection method Methods 0.000 description 13
- 239000011734 sodium Substances 0.000 description 9
- 238000005571 anion exchange chromatography Methods 0.000 description 6
- 239000012470 diluted sample Substances 0.000 description 4
- 238000005303 weighing Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000009210 therapy by ultrasound Methods 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 2
- SYRDSFGUUQPYOB-UHFFFAOYSA-N [Li+].[Li+].[Li+].[O-]B([O-])[O-].FC(=O)C(F)=O Chemical compound [Li+].[Li+].[Li+].[O-]B([O-])[O-].FC(=O)C(F)=O SYRDSFGUUQPYOB-UHFFFAOYSA-N 0.000 description 2
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 2
- 239000004327 boric acid Substances 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 101000878457 Macrocallista nimbosa FMRFamide Proteins 0.000 description 1
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- -1 anion carbonate Chemical class 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000004255 ion exchange chromatography Methods 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/71—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited
- G01N21/73—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited using plasma burners or torches
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/86—Signal analysis
- G01N30/8624—Detection of slopes or peaks; baseline correction
- G01N30/8631—Peaks
Landscapes
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Plasma & Fusion (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Engineering & Computer Science (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a simultaneous determination method of lithium difluoro-oxalato-borate and lithium difluoro-oxalato-borate in lithium battery electrolyte, which comprises the following steps: preparing a matrix solution; preparing a B element standard solution; b element standard solution is taken; preparing a solution to be tested of lithium battery electrolyte B; preparation C 2 O 4 2‑ Standard solution mother liquor; preparation C 2 O 4 2‑ A standard solution; preparation of lithium Battery electrolyte C 2 O 4 2‑ A solution to be measured; sequentially analyzing the matrix solution, the B element standard solution of each concentration gradient and the solution to be tested of the lithium battery electrolyte B by using an inductive coupling plasma emission spectrometer to obtain the content of the B element in the lithium battery electrolyte: respectively for C using anion chromatograph 2 O 4 2‑ Standard solutionElectrolyte C of lithium battery 2 O 4 2‑ Carrying out anion chromatographic analysis on the solution to be detected, and respectively recording peak areas; and calculating the content of the lithium difluorooxalato borate and the lithium difluorooxalato borate. The invention has the advantages that: stable, reliable and accurate, and provides effective means for quantifying the electrolyte components of the lithium battery.
Description
Technical Field
The invention relates to determination of lithium battery electrolyte components, in particular to determination of lithium difluorooxalato borate and lithium dioxaato borate.
Background
Lithium difluorooxalato borate (LiODFB), which is relatively sensitive to water, can decompose oxalate and borate in water, and the decomposition reaction equation is as follows: liBF 2 C 2 O 4 +3H 2 O→Li++2HF+BO 3 - +C 2 O 4 2- +4H + However, boric acid substances belong to weak acids, no ion peak is generated under an anion carbonate system, the fluorine ion peak is generated earlier and gradually reacts with boric acid to be consumed, so the content is unstable, and the fluorine ion peak cannot be used for correction calculation
The content of lithium dioxaborate (LiODFB) is C 2 O 4 2- Ion peaks were located. The hydrolysis anion of LiBOB is still C after meeting water 2 O 4 2- Only C can be used 2 O 4 2- The ion peak was located to correct for LiBOB content.
When either of these two substances is contained alone in the lithium battery electrolyte, the hydrolysis ion peak C thereof can be used 2 O 4 2- And detecting the accurate content of the sample after quantitative analysis. However, when the electrolyte of the lithium battery contains both substances, the peak of the hydrolysis-stable ion is C 2 O 4 2- Therefore, the contents of the two components cannot be accurately measured through the ion peak at the position. However, each component in the lithium battery electrolyte formula has certain concentration requirement, and the concentration of each component in the lithium battery electrolyte formula is used for judging the lithium battery electrolyteWhether the lithium battery electrolyte meets an important reference index of application requirements or not, so that accurate quantification of LiODFB and LiBOB in the lithium battery electrolyte is needed.
Disclosure of Invention
The purpose of the invention is that: the method for simultaneously measuring the lithium difluoroborate and the lithium dioxaborate in the lithium battery electrolyte is high in accuracy and good in stability.
In order to achieve the above purpose, the invention adopts the following technical scheme: the simultaneous determination of lithium difluoro-oxalato-borate and lithium di-oxalato-borate in the lithium battery electrolyte comprises the following steps:
preparing a matrix solution: and (3) diluting the NaOH aqueous solution with pure water until the mass fraction of NaOH is 0.3-0.4%, so as to form a matrix solution.
Preparing a B element standard solution: and (3) taking the B element standard mother solution, and diluting with a matrix solution to respectively form at least three B element standard solutions with gradient concentrations.
Preparing a solution to be tested of lithium battery electrolyte B: calculating the theoretical content of B element in the lithium battery electrolyte to be detected according to the theoretical content of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte to be detected; according to the theoretical content of B, the electrolyte of the lithium battery to be detected is taken and then added into a matrix solution, and the matrix solution is diluted until the theoretical content of B element is the same as or similar to the standard solution concentration of B element with a gradient concentration with lower concentration.
Preparation C 2 O 4 2- Standard solution mother liquor: taking Na 2 C 2 O 4 Diluting with pure water to form C 2 O 4 2- Standard solution mother liquor;
preparation C 2 O 4 2- Standard solution: taking C 2 O 4 2- Standard solution mother liquor is further diluted by pure water to form C 2 O 4 2- A standard solution;
preparation of lithium Battery electrolyte C 2 O 4 2- Solution to be measured: taking electrolyte of a lithium battery to be tested, and diluting the electrolyte with pure water;
measuring B element in the electrolyte of the lithium battery to be measured: using an inductively coupled plasma emission spectrometer (ICP), and sequentially analyzing the matrix solution, the B element standard solution of each concentration gradient and the B solution to be detected of the lithium battery electrolyte by taking the matrix solution as a blank to obtain the B element content;
c in lithium battery electrolyte to be detected 2 O 4 2- Is determined by: using anion chromatograph, regenerating liquid is sulfuric acid solution, eluting liquid is Na 2 CO 3 、NaHCO 3 An acetonitrile water system; respectively pair C 2 O 4 2- Standard solution and lithium battery electrolyte C 2 O 4 2- Carrying out anion chromatographic analysis on the solution to be detected, and respectively recording peak areas;
and (3) calculating: simultaneous equations one and two calculate the contents of lithium difluoroborate and lithium dioxaborate;
equation one:
equation two:
wherein X is the mass percentage of lithium difluoro oxalate borate in the electrolyte of the lithium battery to be detected; y is the mass percentage of lithium dioxalate borate in the electrolyte of the lithium battery to be detected; c (C) Sample B The content of B element in the lithium battery electrolyte to be measured is measured, and the unit ppm is measured; a is that Sample C Is lithium battery electrolyte C 2 O 4 2- C in the solution to be measured 2 O 4 2- Peak area on the anion chromatogram; a is that Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Peak area on the anion chromatogram; c (C) Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Concentration in ppm; multiple times C To prepare lithium battery electrolyte C 2 O 4 2- Multiple of dilution when testing the solution; m is M 4 The molecular weight of the lithium difluorooxalato borate; m is M 3 The molecular weight of the lithium dioxalate borate; m is M 2 Is C 2 O 4 2- Molecular weight of (a); m is M 1 A molecular weight of B; 10000 is a constant.
Further, the simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte is carried out, wherein the matrix solution is diluted by a chromatographic grade 50% NaOH aqueous solution in mass fraction when preparing the matrix solution.
Further, the simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte, wherein C is prepared 2 O 4 2- Na used in mother liquor of standard solution 2 C 2 O 4 Drying and pre-treating, and Na 2 C 2 O 4 For the benchmark reagent grade, the drying step includes: na is mixed with 2 C 2 O 4 Placing the mixture into a porcelain crucible, drying the mixture for 2 hours in an oven at the constant temperature of 100+/-2 ℃, and placing the mixture into a dryer for cooling.
Further, the lithium difluorooxalato borate and the lithium difluorooxalato borate in the lithium battery electrolyte are measured simultaneously, wherein the model of an ion chromatograph is ICS-2100, and the concentration of the regenerated liquid is 0.07mol/L to 0.09mol/L of sulfuric acid solution; na in the eluent 2 CO 3 、NaHCO 3 The concentration of (2) was 2.4mmol/L, with a volume ratio of acetonitrile to water of 1:3.
Further, the simultaneous determination of the lithium difluorooxalato borate and the lithium difluorooxalato borate in the lithium battery electrolyte is carried out, wherein when the B element standard solution is prepared, the B element standard solution with three concentration gradients is formed by diluting the matrix solution until the B content is (0.4+/-0.1) ppm, (0.8+/-0.1) ppm and (1.2+/-0.1) ppm respectively; when the solution to be tested of the lithium battery electrolyte B is prepared, the matrix solution is added to dilute the solution to be the same as or close to (0.4+/-0.1) ppm or (0.8+/-0.1) ppm, and the dilution multiple is not less than 150 times. The dilution factor is not lower than 150, and the aim is to reduce the interference of organic matters in the electrolyte of the lithium battery to be tested on the measurement.
Further, the above-mentioned simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte, wherein, the determination of the content of B element in the lithium battery electrolyte to be measured, according to the theoretical content of B in the lithium battery electrolyte, selects a proper dilution factor, so that the concentration of B in the diluted solution to be measured is close to the standard solution of B element with low concentration, and single standard content correction is performed in the determination process of the content of B element in the lithium battery electrolyte to be measured.
Further, the lithium difluorooxalato borate and lithium difluorooxalato borate in the lithium battery electrolyte are measured simultaneously, wherein when the B element standard solution is prepared, the B element standard solution is an outsourced standard solution for an inductively coupled plasma emission spectrometer (ICP), and the concentration is 1010ppm.
Further, the simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte, wherein the prepared C 2 O 4 2- The concentration of the mother solution of the standard solution is (5000+/-10) ppm; c (C) 2 O 4 2- The concentration of the standard solution is (25+ -5) ppm; preparation of lithium Battery electrolyte C 2 O 4 2- When the solution to be measured is diluted by 50-500 times, the specific dilution is based on C in the electrolyte of the lithium battery 2 O 4 2- The theory content of (2) selects proper dilution factor, the dilution principle is C in the diluted solution 2 O 4 2- Concentration of (C) and C 2 O 4 2- The standard solutions are the same or similar.
The invention has the advantages that: detecting total content of B element in lithium battery electrolyte by adopting a split ICP method, and detecting C element in lithium battery electrolyte by adopting an ion chromatography method 2 O 4 2- The method is feasible, effective and accurate, and can reliably quantify the components in the lithium battery electrolyte, thereby ensuring the quality of the lithium battery electrolyte product.
Drawings
FIG. 1 is a standard curve obtained by ICP measurement in experiment 1.
Detailed Description
The simultaneous measurement of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte according to the present invention is described in detail below.
Description of the reagent: na (Na) 2 C 2 O 4 、Na 2 CO 3 、NaHCO 3 All are reference reagent grades; acetonitrile is an analytically pure grade; the pure water used in the process of diluting the solution and the process of preparing the standard solution is distilled water, which accords with the specification of GB-6682 three-level water; when preparing a matrix solution, adopting a chromatographic pure grade sodium hydroxide aqueous solution with the mass fraction of 50%; when the B standard solution is prepared, the B standard mother solution is a standard solution (standard solution for ICP) for an outsourced inductively coupled plasma emission spectrometer, and the concentration is 1010ppm.
Instrument description: and an inductively coupled plasma emission spectrometer (ICP), wherein the model of the instrument is 5800ICP-OES, the B element in the electrolyte of the lithium battery to be detected is measured, and the detection wavelength is 249.772nm.
Anion chromatograph (ICS-2100) for C in lithium battery electrolyte to be tested 2 O 4 2- The measurement was performed. The anion chromatographic column for the instrument is Shodex SI-904E, the regenerated liquid for the instrument is sulfuric acid solution, and the concentration is 0.07 mol/L-0.09 mol/L; na is adopted as eluent 2 CO 3 And NaHCO 3 Wherein Na is 2 CO 3 Concentration of relative acetonitrile water, naHCO 3 The concentration of water relative to acetonitrile was 2.4mmol/L, with a volume ratio of acetonitrile to water of 1:3.
Preparing a matrix solution: 24.03g of 50% NaOH (chromatographic pure) aqueous solution is weighed, diluted to 4kg by pure water, and the NaOH is 0.3% by mass at the moment, and shaken uniformly for later use.
Preparing a B standard solution: respectively weighing 0.0415g, 0.0843g and 0.1236g of B element standard mother solution, diluting with matrix solution to 100.0234g, 100.2457g and 100.4565g to respectively form three B standard solutions with gradient concentration, wherein the B content in the B standard solutions is 0.4190ppm, 0.8493ppm and 1.2427ppm. And are named B1, B2, B3 in order for convenience of description.
The lithium battery electrolyte with three formulas is used as three lithium battery electrolytes to be tested, namely a 1# lithium battery electrolyte, a 2# lithium battery electrolyte and a 3# lithium battery electrolyte. The mass percentage of LiODFB in the No. 1 lithium battery electrolyte is 0.302%, and the lithium battery electrolyte does not contain LiBOB; the mass percentage of LiBOB in the No. 2 lithium battery electrolyte is 0.116%, and the lithium battery electrolyte does not contain LiODFB; the mass percent of LiODFB in the 3# lithium battery electrolyte is 0.293%, and the mass percent of LiBOB is 0.112%.
Preparation C 2 O 4 2- Mother liquor: reference reagent Na 2 C 2 O 4 Placing the mixture into a porcelain crucible, drying the mixture for 2 hours in an oven with the temperature of 100+/-2 ℃ at constant temperature, and then placing the mixture into a dryer for cooling. Then weighing the dried and cooled Na 2 C 2 O 4 Diluted with pure water to 5006.4ppm.
Preparation C 2 O 4 2- Standard solution: 0.5046gC is taken 2 O 4 2- The mother liquor was diluted with pure water to 21.68ppm.
Experiment 1: and (3) measuring the B element in the lithium battery electrolyte by using an inductively coupled plasma emission spectrometer, and then converting according to the molecular weight to obtain the LiODFB/LiBOB content. For simplicity of description, the inductively coupled plasma emission spectrometer will be hereinafter simply referred to as ICP, and the inductively coupled plasma emission spectrometer measurement will be simply referred to as ICP measurement.
The method comprises the following steps: preparing a No. 1 sample to be tested: 0.4023g of No. 1 lithium battery electrolyte is weighed, diluted to 114.3218g by a matrix solution, the theoretical concentration of B element after dilution is 0.7989ppm, the dilution multiple is 284.2 times, and the diluted sample is uniformly shaken and then subjected to ultrasonic treatment for 30min to be measured.
Preparing a No. 2 sample to be tested: 0.6423g of No. 2 lithium battery electrolyte is weighed, diluted to 102.7685g by a matrix solution, the theoretical concentration of B element after dilution is 0.4044ppm, the dilution multiple is 160 times, and the diluted sample is uniformly shaken and then subjected to ultrasonic treatment for 30min to be measured.
Sample detection: the matrix solution is blank, and after ICP is started stably, the blank, the B1, the B2, the B3, the 1# sample to be detected and the 2# sample to be detected are detected respectively, the detection wavelength is 249.678nm, the linearity of the standard curve is shown in figure 1, and the linearity is good in figure 1. And B1 or B2 which is similar to the theoretical content of the diluted sample to be detected is selected for single standard content correction, so that the influence of factors such as environmental change, long time interval and the like can be overcome, and the accuracy of a result is further improved.
The results obtained by converting the molecular weight according to the content of B obtained by ICP detection of the samples # 1 and # 2 to be detected are shown in Table 1.
Table 1:
the data in table 1 shows: the content of B element in the lithium battery electrolyte is measured by using an inductive coupling plasma emission spectrometer, and then the content of LiODFB/LiBOB is obtained by conversion according to the molecular weight.
Experiment 2: determination of C in lithium battery electrolyte by anion chromatograph 2 O 4 2- And (3) quantifying the contents of LiODFB and LiBOB in the lithium battery electrolyte, and verifying theoretical values of the contents of LiODFB and LiBOB in the lithium battery electrolyte.
The method comprises the following specific steps: preparation of lithium Battery electrolyte C 2 O 4 2- Sample to be measured: taking the No. 1 lithium battery electrolyte, directly diluting the No. 1 lithium battery electrolyte with pure water for about 100 times, and shaking the solution uniformly to form the No. 1 lithium battery electrolyte C 2 O 4 2- And (5) testing a sample. Taking electrolyte of a No. 2 lithium battery, directly diluting the electrolyte with pure water for about 50 times, and shaking the diluted electrolyte evenly to form electrolyte C of the No. 2 lithium battery 2 O 4 2- And (5) testing a sample.
Anion chromatography detection: after the starting-up baseline is stabilized for 30 minutes, C is respectively carried out 2 O 4 2- Standard solution, no. 1 and No. 2 lithium battery electrolyte C 2 O 4 2- The sample to be measured is subjected to anion chromatographic analysis, and C is recorded respectively 2 O 4 2- Is a peak area of (c). The procedure and result data are shown in table 2.
TABLE 2
The detection data obtained in the experiment 1 are compared with the detection data obtained in the experiment 2, and the theoretical data are compared to obtain: the method for determining the B element by ICP and then quantifying LiODFB/LiBOB according to the conversion of molecular weight has accurate data. Therefore, a method of measuring the B element by ICP and quantifying LiODFB/LiBOB by conversion of molecular weight is possible.
Experiment 3: ICP measurement of B element the stability of LiODFB/LiBOB method was tested in this quantitative manner.
The method comprises the following specific steps: 5 samples were taken of each of the 1# lithium battery electrolyte and the 2# lithium battery electrolyte. Each sample was analyzed by the same procedure as in experiment 1, and the test results are shown in tables 3 and 4.
TABLE 3 Table 3
TABLE 4 Table 4
From the data in tables 3 and 4, it can be obtained: the data parallelism is good, namely, the stability of the method for quantifying LiODFB/LiBOB by measuring B element through ICP and then converting the molecular weight is good.
Experiment 4: and on the premise that the method for quantifying LiODFB/LiBOB by measuring B element through ICP is stable and feasible, measuring the electrolyte of the 3# lithium battery.
The method comprises the following steps:
preparing a solution to be tested of lithium battery electrolyte B: weighing 0.3301g of No. 3 lithium battery electrolyte, diluting to 115.4237g by using a matrix solution, wherein the theoretical concentration of B element after dilution is 0.8086ppm, and the dilution multiple is 349.66 times; shaking the diluted sample uniformly, and carrying out ultrasonic treatment for 30min to obtain the sample to be tested.
ICP detection: and (3) detecting the blank, the B1, the B2, the B3, the solution to be detected of the lithium battery electrolyte B and the standard solution B1 or B2 respectively after the ICP is started stably.
Preparation of lithium Battery electrolyte C 2 O 4 2- Solution to be measured: weighing 0.5442g of 3# lithium battery electrolyte, and using pureDiluting the mixture to 66.6457g by water, shaking the mixture evenly and then measuring the mixture.
Anion chromatography detection: after the starting-up baseline is stabilized for 30 minutes, C is respectively carried out 2 O 4 2- Standard solution and lithium battery electrolyte C 2 O 4 2- The solution to be measured is subjected to anion chromatographic analysis, and C is recorded respectively 2 O 4 2- Is a peak area of (c).
The content of B element obtained by analysis and determination according to ICP method, and C obtained by anion chromatography 2 O 4 2- And (3) corresponding to the standard solution, and simultaneously calculating the percentage content of LiODFB and LiBOB in the 3# lithium battery electrolyte by using the first and second simultaneous equations.
Equation one:
equation two:
wherein X is the mass percentage of lithium difluoro oxalate borate in the electrolyte of the lithium battery to be detected; y is the mass percentage of lithium dioxalate borate in the electrolyte of the lithium battery to be detected; c (C) Sample B The content of B element in the lithium battery electrolyte to be measured is measured, and the unit ppm is measured; a is that Sample C Is lithium battery electrolyte C 2 O 4 2- C in the solution to be measured 2 O 4 2- Peak area on the anion chromatogram; a is that Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Peak area on the anion chromatogram; c (C) Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Concentration in ppm; multiple times C To prepare lithium battery electrolyte C 2 O 4 2- Multiple of dilution when testing the solution; m is M 4 The molecular weight of the lithium difluorooxalato borate is 143.79; m is M 3 The molecular weight of the lithium dioxalate borate is 193.79; m is M 2 Is C 2 O 4 2- Molecular weight of (2) and a value of 88; m is M 1 The molecular weight of B is 10.81;10000 is a constant. The experimental procedure and the detection data are shown in table 5.
TABLE 5
From the above, it can be seen that: the data is accurate, namely, the contents of LiODFB and LiBOB in the lithium battery electrolyte can be accurately detected through simultaneous determination of the lithium difluoroborate and the lithium dioxaborate in the lithium battery electrolyte.
Experiment 5: and performing stability analysis on simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte.
Five groups of samples are taken from the 3# lithium battery electrolyte, one sample in each group of samples is diluted by a matrix solution to prepare a solution to be tested of the lithium battery electrolyte B, and ICP detection B is carried out; diluting another sample with pure water to prepare lithium battery electrolyte C 2 O 4 2- Detecting C by anion chromatography of the solution to be detected 2 O 4 2- . In each group of samples, the step of detecting B by ICP is the same as the corresponding step in experiment 4, and the content of B element obtained by analysis and measurement of the ICP method is recorded; anion chromatography detection C 2 O 4 2- The procedure of (2) was the same as the corresponding procedure in experiment 4, and the obtained C was recorded by anion chromatography 2 O 4 2- Is a peak area of (c). And according to the corresponding data obtained by detection of each group of samples, simultaneous equations one and two are listed in the embodiment 4, and the percentage contents of LiODFB and LiBOB in the 3# lithium battery electrolyte are calculated. The test results of experiment 5 are shown in Table 6.
TABLE 6
From the above experiments, it can be obtained: according to the method, the simultaneous determination of the difluoro oxalic acid lithium borate and the difluoro oxalic acid lithium borate in the lithium battery electrolyte is realized, and the method is stable, reliable and good in accuracy, so that an effective means for accurate and quantitative stopping and supplying of components in the lithium battery electrolyte can be realized, and the quality of a lithium battery electrolyte product is ensured.
Claims (8)
1. The simultaneous determination of lithium difluoro-oxalato-borate and lithium di-oxalato-borate in the lithium battery electrolyte comprises the following steps:
preparing a matrix solution: diluting NaOH aqueous solution with pure water until the mass fraction of NaOH is 0.3-0.4%, and forming a matrix solution;
preparing a B element standard solution: taking a B element standard mother solution, and diluting with a matrix solution to respectively form at least three B element standard solutions with gradient concentrations;
preparing a solution to be tested of lithium battery electrolyte B: calculating the theoretical content of B element in the lithium battery electrolyte to be detected according to the theoretical content of lithium difluorooxalato borate and lithium dioxaato borate in the lithium battery electrolyte to be detected; according to the theoretical content of B, adding a matrix solution after taking the lithium battery electrolyte to be tested, and diluting until the theoretical content of B element is the same as or similar to the concentration of B element standard solution with a gradient concentration with lower concentration;
preparation C 2 O 4 2- Standard solution mother liquor: taking Na 2 C 2 O 4 Diluting with pure water to form C 2 O 4 2- Standard solution mother liquor;
preparation C 2 O 4 2- Standard solution: taking C 2 O 4 2- Standard solution mother liquor is further diluted by pure water to form C 2 O 4 2- A standard solution;
preparation of lithium Battery electrolyte C 2 O 4 2- Solution to be measured: taking electrolyte of a lithium battery to be tested, and diluting the electrolyte with pure water;
measuring B element in the electrolyte of the lithium battery to be measured: using an inductively coupled plasma emission spectrometer, and sequentially analyzing the matrix solution, the B element standard solution of each concentration gradient and the B solution to be detected of the lithium battery electrolyte by taking the matrix solution as a blank to obtain the B element content;
c in lithium battery electrolyte to be detected 2 O 4 2- Is determined by: using anion chromatograph, regenerating liquid is sulfuric acid solution, eluting liquid is Na 2 CO 3 、NaHCO 3 An acetonitrile water system; respectively pair C 2 O 4 2- Standard solution and lithium battery electrolyte C 2 O 4 2- Carrying out anion chromatographic analysis on the solution to be detected, and respectively recording peak areas;
and (3) calculating: simultaneous equations one and two calculate the contents of lithium difluoroborate and lithium dioxaborate;
equation one:
equation two:
wherein X is the mass percentage of lithium difluoro oxalate borate in the electrolyte of the lithium battery to be detected; y is the mass percentage of lithium dioxalate borate in the electrolyte of the lithium battery to be detected; c (C) Sample B The content of B element in the lithium battery electrolyte to be measured is measured, and the unit ppm is measured; a is that Sample C Is lithium battery electrolyte C 2 O 4 2- C in the solution to be measured 2 O 4 2- Peak area on the anion chromatogram; a is that Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Peak area on the anion chromatogram; c (C) Label C Is C 2 O 4 2- C in Standard solution 2 O 4 2- Concentration in ppm; the multiple C is used for preparing the lithium battery electrolyte C 2 O 4 2- Multiple of dilution when testing the solution; m is M 4 The molecular weight of the lithium difluorooxalato borate; m is M 3 The molecular weight of the lithium dioxalate borate; m is M 2 Is C 2 O 4 2- Molecular weight of (a); m is M 1 A molecular weight of B; 10000 is a constant.
2. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: in preparing the matrix solution, dilution is performed with a chromatographic grade 50% by mass aqueous NaOH solution.
3. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: preparation C 2 O 4 2- Na used in mother liquor of standard solution 2 C 2 O 4 Drying and pre-treating, and Na 2 C 2 O 4 For the benchmark reagent grade, the drying step includes: na is mixed with 2 C 2 O 4 Placing the mixture into a porcelain crucible, drying the mixture for 2 hours in an oven at the constant temperature of 100+/-2 ℃, and placing the mixture into a dryer for cooling for standby.
4. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: the model of the ion chromatograph is ICS-2100, the anion chromatographic column is Shodex SI-904E, and the concentration of the regenerated liquid is sulfuric acid solution and is 0.07 mol/L-0.09 mol/L; na in the eluent 2 CO 3 、NaHCO 3 The concentration of (2) was 2.4mmol/L, with a volume ratio of acetonitrile to water of 1:3.
5. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: when preparing the B element standard solution, diluting the B element standard solution with a matrix solution until the B content is (0.4+/-0.1) ppm, (0.8+/-0.1) ppm and (1.2+/-0.1) ppm respectively to form three concentration gradient B element standard solutions; when preparing the solution to be tested of the lithium battery electrolyte B, adding the matrix solution to dilute to be the same as or close to (0.4+/-0.1) ppm or (0.8+/-0.1) ppm, and the dilution multiple is not less than 150 times.
6. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: and (3) carrying out single standard content correction in the measurement process of the B element in the lithium battery electrolyte to be measured.
7. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: when the B element standard solution is prepared, the B element standard mother solution is outsourced standard solution for the inductively coupled plasma emission spectrometer, and the concentration is 1010ppm.
8. The simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in a lithium battery electrolyte according to claim 1, wherein: prepared C 2 O 4 2- The concentration of the mother solution of the standard solution is (5000+/-10) ppm; c (C) 2 O 4 2- The concentration of the standard solution is (25+ -5) ppm; preparation of lithium Battery electrolyte C 2 O 4 2- When the solution to be measured is diluted by 50-500 times.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210522827.3A CN117092089A (en) | 2022-05-13 | 2022-05-13 | Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210522827.3A CN117092089A (en) | 2022-05-13 | 2022-05-13 | Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117092089A true CN117092089A (en) | 2023-11-21 |
Family
ID=88772291
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210522827.3A Pending CN117092089A (en) | 2022-05-13 | 2022-05-13 | Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117092089A (en) |
-
2022
- 2022-05-13 CN CN202210522827.3A patent/CN117092089A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105467058B (en) | Method for detecting carboxylic ester compounds in lithium ion battery electrolyte | |
| CN103454351B (en) | Ion chromatographic method for simultaneously measuring trace amount of anions in high-purity phosphoric acid | |
| CN104730139A (en) | Method for analyzing fluorine ion concentration under radioactive condition | |
| CN109212112B (en) | Method for detecting inorganic salt in lithium ion electrolyte | |
| CN102128900A (en) | Method for detecting components of alumyte | |
| CN101101279A (en) | Quantitative analysis method for battery electrolyte organic components | |
| CN102937614A (en) | Method for analyzing content of free fluorin in lithium ion battery electrolyte salt LiBF4 | |
| CN103293114A (en) | Visual colorimetry for determination of phosphates | |
| CN112113953B (en) | Quantitative detection method for element content in carbon composite lithium iron phosphate | |
| CN117092089A (en) | Simultaneous determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte | |
| CN111474280A (en) | Method for detecting trace aluminum element in compound amino acid injection | |
| CN116008459A (en) | Quantitative detection method for purity of sodium bisoxalato borate | |
| CN111443078A (en) | Method for simultaneously detecting contents of trace As, Pb, Cd, Zn and Cr elements in ferrous chloride | |
| CN107807150A (en) | A kind of detection method of inorganic electrolyte lithium salt content | |
| Chen et al. | A novel approach to evaluate the extent and the effect of cross-contribution to the intensity of ions designating the analyte and the internal standard in quantitative GC-MS analysis | |
| CN114924019A (en) | Method for testing chloride in bis (fluorosulfonyl) imide | |
| CN117250291A (en) | Determination of lithium difluorooxalato borate and lithium dioxaato borate in lithium battery electrolyte | |
| CN113030286B (en) | Determination of hexamethyldisilazane content in tris (trimethylsilyl) phosphate | |
| CN110631874B (en) | Sample pretreatment method for determining content of silicon element in polymer and method for determining content of silicon element in polymer | |
| CN113670835A (en) | Method for analyzing phosphorus content in serpentine | |
| CN112730385A (en) | Detection method for determining contents of silicon and phosphorus elements in ferrochrome by utilizing ICP (inductively coupled plasma) | |
| CN111141725A (en) | Quantitative detection method for lithium hexafluorophosphate in lithium ion battery electrolyte | |
| CN110057967A (en) | Aluminum ions quantitative detecting method in a kind of aluminum electric pole foil corrosive liquid | |
| CN115047101B (en) | Detection method and application of methylene methane disulfonate | |
| CN112213299B (en) | Method for determining TMSB in lithium battery electrolyte |
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 |