shows the chromatogram with conductivity detection of the above-mentioned LiPF 6 aqueous solution stored for four weeks at room temperature. Battery grade lithium hexafluorophosphate was ordered from SigmaeAldrich Chemie GmbH (Steinheim, Germany). Plakhotnyk et al. Investigations and identification of decomposition products with a new method in an LIB electrolyte. For IC/ESI-MS analysis, the IC system was directly connected to the ionization interface using PEEK tubing with an i.d. Front Chem. Bethesda, MD 20894, Web Policies All chemicals were of the highest quality available. Sorry, preview is currently unavailable. official website and that any information you provide is encrypted The injection volume was 20 mL. 2021 Sep 1;9:727382. doi: 10.3389/fchem.2021.727382. Aqueous samples of lithium hexafluorophosphate (LiPF(6)), sodium hexafluorophosphate (NaPF(6)) and potassium hexafluorophosphate (KPF(6)) were prepared and stored for different times. For IC/ICP-OES measurements, a SPECTRO ARCOS from SPECTRO Analytical Instruments GmbH (Kleve, Germany) was used with a cyclone spray chamber and a MiraMist Teflon nebulizer (Burgener, Mississauga, Ontario, Canada). The conductivity detector was also used for comparison. Preparation of Furfural From Xylose Catalyzed by Diimidazole Hexafluorophosphate in Microwave. Lithium ion batteries (LIBs) are one of the most important energy sources for portable electronic devices, e.g. (2) and monofluorophosphate were detected as well. Since the carbonates release CO 2 during the aging process, the resulting alcohols act as an additional reaction source. In a previous work it was shown the usefulness of ion chromatography to investigate the decomposition products of LiPF 6 . In literature the following steps for the hydrolysis of LiPF 6 are reported to take place [8e11]: LiPF 6 %Li PF 6 (1) LiPF 6 %LiF PF (2). However, considering the hydrolysis rate, which is described in literature as slow, peak 4 could belong to hexafluorophosphate . Chromatographic separation and identification of products from the reaction of dimethylarsinic acid with hydrogen sulfide. Additionally, due to the high hygroscopicity of LiPF 6 , battery grade electrolytes contain about 25 ppm water , which favors spontaneous decomposition reactions since LiPF 6 is decomposed in the presence of water . Combining the results showed above with GC-MS measurements, which confirmed phosphorus oxyfluoride and diethylfluorophosphate, a preliminary reaction cycle is proposed ) for the electrolyte system regarding thermal aging. 2019 Apr 11;9(20):11413-11419. doi: 10.1039/c9ra01291e. Unable to load your collection due to an error, Unable to load your delegates due to an error. Stenzel YP, Henschel J, Winter M, Nowak S. RSC Adv. The PEEK tubing was directly connected to a MiraMist Teflon nebulizer (Burgener, Mississauga, Ontario, Canada) and a cyclonic spray chamber, which was operated at room temperature. Besides hexafluorophosphate, four other anionic species were detected in fresh and matured aqueous solutions. Additionally peak (2) revealed a contribution from FPO 3 C 2 H 5 while peak (4) was generated by the following decomposition products FPO 4 C 4 H 10 , FPO 5 C 6 H 14 and FPO 6 C 8 H 18, which were all detected as single charged anions. They suggested that POF 3 further decomposes in presence of water to difluorophosphoric acid (POF 2 (OH)). J Chromatogr A. Besides its dissociation to Li and PF 6 , LiPF 6 is also in equilibrium with lithium fluoride (LiF) and phosphorus pentafluoride (PF 5 ) in aqueous solution. For isocratic separations, the mobile phase consisted of a solution of 2.0 mmol L 1 sodium bicarbonate and 4.2 mmol L 1 sodium carbonate in a mixture of 30% acetonitrile (AcN) and 70% water (v/v). Gu S, Wang J, Kaspar RB, Fang Q, Zhang B, Bryan Coughlin E, Yan Y. Sci Rep. 2015 Jun 29;5:11668. doi: 10.1038/srep11668. Would you like email updates of new search results? Careers. In this case, the decomposition rate of LiPF 6 decreases, which entails less electrolyte degradation in the cell. The Role of Sub- and Supercritical CO2 as "Processing Solvent" for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes. The corresponding chromatograms recorded with ESI-MS in single ion mode (SIM) are presented in . However, in this work UVevis detection was replaced with conductivity detection and for unknown compounds, electrospray ionization mass spectrometry (ESI-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES) were complementary used for detection and identification purposes. Ion chromatographic determination of hydrolysis products of hexafluorophosphate salts in aqueous solution, The influence of different conducting salts on the metal dissolution and capacity fading of NCM cathode material, Role of PF 6 in the radiolytical and electrochemical degradation of propylene carbonate solutions, Aging of Li2FeSiO4 cathode material in fluorine containing organic electrolytes for lithium-ion batteries, Investigations on the electrochemical performance and thermal stability of two new lithium electrolyte salts in comparison to LiPF6, APPLICATIONS OF IONIC LIQUIDS IN SCIENCE AND TECHNOLOGY, Dendrite-free Li deposition using trace-amounts of water as an electrolyte additive, Aging stability of Li2FeSiO4 polymorphs in LiPF6 containing organic electrolyte for lithium-ion batteries, Extraction of lithium-ion battery electrolytes with liquid and supercritical carbon dioxide and additional solvents, Is 3-methyl-2-oxazolidinone a suitable solvent for lithium-ion batteries, Batterie Litio-ione: sulla catena degli eventi termici che pu condurre a esplosione ed incendio MINISTERO DELLO SVILUPPO ECONOMICO, LiBOB as Salt for Lithium-Ion Batteries:A Possible Solution for High Temperature Operation, Physicochemical and electrochemical investigations of the ionic liquid N-butyl -N-methyl-pyrrolidinium 4,5-dicyano-2-(trifluoromethyl) imidazole, Studies on ionic liquidbased corn starch biopolymer electrolytes coupling with high ionic transport num, Studies on ionic liquid-based corn starch biopolymer electrolytes coupling with high ionic transport number, Anion Effects on Solid Polymer Electrolytes Containing Sulfur Based Ionic Liquid for Lithium Batteries, Solid polymer electrolytes with sulfur based ionic liquid for lithium batteries, Block Copolymer Electrolyte with Sulfur Based Ionic Liquid for Lithium Batteries, A conductivity study of preferential solvation of lithium ion in acetonitrile-dimethyl sulfoxide mixtures, Syntheses of a wide variety of new aryl based perfluorosulfonimide lithium salt. This indicates that only a small amount of water is needed to start the decomposition processes, which kinetics are, on the other hand, highly increased by temperature. Complementary analyses for identification purposes were therefore performed by IC/ICP-OES and IC/ESI-MS, which results are presented in the following. eCollection 2019 Apr 9. For future work, a gradient step should be applied instead of the isocratic step, since some of the new compounds, especially those detected at peaks 2 and 4 in , could not be baseline separated. Copyright 2011 Elsevier B.V. All rights reserved. Here, several new decomposition products appear due to the temperature influence on the system. Chem Res Toxicol. Proposed reaction cycle for the electrolyte system. As a further step towards the understanding of aging phenomena in LIBs, the ion chromatography (IC) method presented in this work was developed to separate the decomposition products of LiPF 6 and other compounds formed during the thermal aging of a commercially available electrolyte system EC/DEC (3:7 w/w). Baseline separation was obtained for all of the decomposition products. Furthermore, the relative peak areas of fluoride and difluorophosphate in the electrolyte solution are relatively small compared with that of hexafluorophosphate, which is the far most intense peak in . For identification of the detected decomposition products, the IC was connected to ESI-MS. MeSH However, using LiPF 6 is disadvantageous due to its thermal instability as observed by differential scanning calorimetry (DSC) and adiabatic calorimetry (ARC) . The separation efficiency of IC allowed baseline separation of all investigated analytes within less than 13 min. A Basic IC 792 ion chromatograph and an 881 Compact IC pro Anion MCS from Metrohm AG (Herisau, Switzerland) were used for IC measurements. 2003;17(14):1517-27. doi: 10.1002/rcm.1030. Furthermore, it was demonstrated that the determination and identification of decomposition products in commercial battery electrolyte solutions are possible using the newly developed methods. Difluorophosphoric acid 2 was detected with m/z 100.9 at t R 4.25 min, monofluorophosphoric acid 3 with m/ z 99.0 at t R 7.36 min and hexafluorophosphate 4 with m/ z 145.0 at t R 11.01 min. Fricke MW, Zeller M, Sun H, Lai VW, Cullen WR, Shoemaker JA, Witkowski MR, Creed JT. Thus, a totally different mechanism must take place already at 35 C, which, involving the carbonate solvents, results in the generation of several alkyl-and alkoxy phosphates. Huang T, Yuan K, Nie XL, Chen J, Zhang HX, Chen JZ, Xiong WM. While peak 1 was identified as fluoride (see Section 3.1), PF 6 (4), difluorophosphate. The compounds were analyzed first with conductivity and afterwards with ESI-MS detection. Afterwards the electrolyte was stored at room temperature. ESI-MS parameters are presented in . The flow rate of the mobile phase was 0.9 mL min 1 . Anhydrous sodium carbonate (Na 2 CO 3 ), sodium bicarbonate (NaHCO 3 ) and battery electrolyte were purchased from Merck KGaA (Darmstadt, Germany). Comparing the chromatograms of LiPF 6 in water ) or electrolyte ), it appears as in the latter the area of monofluorophosphate is almost negligible. To browse Academia.edu and the wider internet faster and more securely, please take a few seconds toupgrade your browser. The software used for controlling the IC was the 792 Basic IC 1.0 (Metrohm). Three baselineseparated peaks (peaks 2, 3 and 4) were detected. 2015 Aug 28;1409:201-9. doi: 10.1016/j.chroma.2015.07.054. Fluoride was identified by standard. Molecules. It is interesting to point out that the influence of temperature had a more important impact on the decomposition process than the spiked water, although only a minor increase from 25 C to 35 C was investigated. Permethyl Cobaltocenium (Cp*2Co+) as an Ultra-Stable Cation for Polymer Hydroxide-Exchange Membranes. Novel methods based on hyphenated analytical techniques for the analysis of LiPF 6 commercially available battery electrolytes are presented. Ion chromatography (IC) with UV as well as non-suppressed and suppressed conductivity detection was used for the analysis of the reaction products. HHS Vulnerability Disclosure, Help IC/ESI-MS was used to identify the compounds separated by IC, as described earlier. government site. PMC of 0.25 mm. It was shown that stability of hexafluorophosphate solutions depends on the nature of the counter ion and decreases in the order potassium>sodium>lithium. The hydrolysis products fluoride (F(-)), monofluorophosphate (HPO(3)F(-)), phosphate (HPO(4)(2-)) and difluorophosphate (PO(2)F(2)(-)) were found and were unambiguously identified by means of standards or electrospray ionization mass spectrometry (ESI-MS). Determination of low-molecular-mass aliphatic carboxylic acids and inorganic anions from kraft black liquors by ion chromatography. and transmitted securely. Kraft V, Grtzke M, Weber W, Menzel J, Wiemers-Meyer S, Winter M, Nowak S. J Chromatogr A. The eluting analytes were ionized in the ESI interface in the negative ion mode. Two-dimensional ion chromatography for the separation of ionic organophosphates generated in thermally decomposed lithium hexafluorophosphate-based lithium ion battery electrolytes. Based on Karl Fischer measurements, the electrolyte contained 25 ppm of water. A Metrosep Supp 4/5 guard (Metrohm) was used to avoid contamination of the analytical column. Epub 2014 Jun 7. This site needs JavaScript to work properly. which is followed by the reaction between the formed POF 2 (OH) and water under formation of monofluorophosphoric acid (POF(OH) 2 ): The proposed decomposition products including structural formula and molecular weight are depicted in . The decomposition products were identified by their m/z ratio. In , the chromatogram (conductivity detection) of a commercially available battery electrolyte containing LiPF 6 is presented. FOIA Acetonitrile (AcN, HPLC grade) was obtained from VWR International GmbH (Darmstadt, Germany). The chromatogram reveals three peaks, since F cannot be analyzed by this mode, but was already identified earlier. mobile phones or notebooks . In , the chromatogram of the commercially available electrolyte (without water addition) stored at 35 C for the same time (4 weeks) is shown. For the detection and identification of the formed decomposition products, an IC method using IonPac AS14A 250 mm 4.0 mm i.d. This results support for very different decomposition rates resulting from the lower dielectric constant of the electrolyte . A commercially available battery electrolyte containing 1 mol L 1 LiPF 6 with EC/DEC (3:7 w/w) was spiked with 600 ppm (3.3 10 2 mol L 1 ) of purified water. By comparison with a standard, peak 1 was identified as fluoride. eCollection 2021. Electrochemical performances of the related polymer electrolytes, On the limited performances of sulfone electrolytes towards the LiNi0.4Mn1.6O4 spinel, Stability of Ionic Liquids in Application Conditions, Preparation of microporous Cellulose/Poly(vinylidene fluoride- hexafluoropropylene) membrane for lithium ion batteries by phase inversion method, Syntheses of a wide family of new aryl based perfluorosulfonimide lithium salts. The IC system was coupled to the ICP-OES using PEEK tubing with an inner diameter (i.d.) Both systems consisted of a suppressor for chemical suppression, which acts as a cation exchanger to remove cations and replace them with an H so that the background noise is lowered to 1 mS and a conductivity detector. Clipboard, Search History, and several other advanced features are temporarily unavailable. Purified water (18.2 MU 1 cm 1 , TOC <4 ppb, Milli-Q Advantage A10, Millipore GmbH, Schwalbach, Germany) was used for all experiments. A new HILIC-ICP-SF-MS method for the quantification of organo(fluoro)phosphates as decomposition products of lithium ion battery electrolytes. Four peaks were detected with the following retention time: 1 3.45 min, 2 4.25 min, 3 7.37 min and 4 10.86 min. 2017 Mar 6;22(3):403. doi: 10.3390/molecules22030403. A non-spiked electrolyte sample was stored at 35 C for the thermal aging investigations to show the different impact of temperature in contrast to water content. Subsequently, the same commercially available electrolyte system was analyzed to prove the usefulness of the proposed method to investigate the influence of the thermal aging in lithiumion batteries. The site is secure. The .gov means its official. 8600 Rockville Pike ICP-OES parameters are presented in . Kkl JM, Aln RJ, Isoaho JP, Matilainen RB. To get some information about the element composition of each peak the IC was coupled with the ICP-OES. The sample was spiked with 600 ppm of water and stored at room temperature for several weeks. Further peaks in the chromatogram could not identified by IC using conductivity detection. Disclaimer, National Library of Medicine Additionally, the relatively low amount of water present in the commercial electrolyte (up to 25 ppm) is certainly not enough for reactions (3)e(5) (see above) to proceed since water is stoichiometrically involved in these reactions. This is important for the quantification of the decomposition products using IC/ICP-OES or IC/ICP-MS since there are no commercially available standards available today. Notice that in order to avoid peak overlapping the sample was additionally tenfold diluted. Kraft V, Grtzke M, Weber W, Winter M, Nowak S. J Chromatogr A. Ion chromatography electrospray ionization mass spectrometry method development and investigation of lithium hexafluorophosphate-based organic electrolytes and their thermal decomposition products. The https:// ensures that you are connecting to the All the compounds which were found in the water spiked sample were also present in this chromatogram: (1), fluoride, (3), difluorophosphate (5), PF and monofluorophosphate. The SPECTRO ARCOS was controlled by the Smart Analyzer Vision 4.0 software (SPECTRO). Epub 2015 Jul 16. Furthermore, studies have shown that difluorophosphate (F 2 PO 2 ) can be formed by the hydrolysis reaction [16e19]. sharing sensitive information, make sure youre on a federal Electrochemical performances of the related polymer electrolytes, The Mechanism of SEI Formation on Single Crystal Si (110), Si(110) and Si(111) Electrodes, XPS, XRD and SEM characterization of a thin ceria layer deposited onto graphite electrode for application in lithium-ion batteries, Radiolysis as a solution for accelerated ageing studies of electrolytes in Lithium-ion batteries, Interface layer formation in solid polymer electrolyte lithium batteries: an XPS study, The synthesis of 1,8-naphthalimide groups containing imidazolium salts/ionic liquids using I, PF6, TFSI anions and their photophysical, electrochemical and thermal properties, Study on the decomposition mechanism of alkyl carbonate on lithium metal by pyrolysis-gas chromatography-mass spectroscopy, Modeling Thermal Abuse in Transportation Batteries, Concentrated electrolytes: decrypting electrolyte properties and reassessing Al corrosion mechanisms, New type of imidazole based salts designed specifically for lithium ion batteries, Infrared Spectroscopy Studies on Stability of Dimethyl Sulfoxide for Application in a LiAir Battery, Beneficial influence of succinic anhydride as electrolyte additive on the self-discharge of 5V LiNi0.4Mn1.6O4 cathodes, Enhanced thermal stability of a lithiated nano-silicon electrode by fluoroethylene carbonate and vinylene carbonate, Improved lithium manganese oxide spinel/graphite Li-ion cells for high-power applications, Mechanism of hydrofluoric acid formation in ethylene carbonate electrolytes with fluorine salt additives, Electrochemical studies of ferrocene in a lithium ion conducting organic carbonate electrolyte, Effects of Electrolyte Salts on the Performance of LiO 2 Batteries, The role of Li-ion battery electrolyte reactivity in performance decline and self-discharge, Highly ionic conducting methacrylic-based gel-polymer electrolytes by UV-curing technique, Ion conducting corn starch biopolymer electrolytes doped with ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, An experimental and theoretical correlation to account for the effect of LiPF 6 concentration on the ionic conductivity of poly(poly (ethylene glycol) methacrylate, Comparing Triflate and Hexafluorophosphate anions of Ionic Liquid in Polymer Electrolytes for Supercapacitor Applications, Controlling Oxidation Potentials in Redox Shuttle Candidates for Lithium-Ion Batteries, Effect of monocationic ionic liquids as electrolyte additives on the electroche mical and therm al properties of Li-ion batteries. The sample was stored four weeks at room temperature. of 0.25 mm. Federal government websites often end in .gov or .mil. Separation of the hydrolysis products of LiPF 6 was carried out using an anion separation column model Metrosep Supp 4 (Metrohm, Herisau, Switzerland) with the following dimensions: 250 mm length 4.0 mm i.d., 9 mm particle size. You can download the paper by clicking the button above. A novel method for the analysis of LiPF 6 and battery electrolytes was presented. In the ESI-MS chromatogram of the aqueous LiPF 6 sample is shown. 2008 May 9;1190(1-2):150-6. doi: 10.1016/j.chroma.2008.02.096. Accessibility Academia.edu no longer supports Internet Explorer. Electrospray ionization mass spectrometry coupled to liquid chromatography for detection of cisplatin and its hydrated complexes. According to these studies and the proposed hydrolysis reaction scheme, it is expected that the peaks might consist of difluorophosphoric acid and monofluorophosphoric acid. For the hyphenation of IC with ICP-OES or ESI-MS a solution of 1 mmol L 1 LiPF 6 in water was prepared, which was stored at room temperature. The API2000 and QTRAP3200 were controlled by the Analyst 1.4.1 and 1.5.1 softwares respectively, (both from Applied Biosystems). A preliminary reaction cycle was proposed for the thermal decomposition of the investigated system. Qualitative analysis of LiPF 6 based on IC with a conductivity detector, IC/ESI-MS and IC/ICP-OES was carried out to identify its decomposition products in aqueous solution. For IC/ESI-MS measurements, an API2000 and a QTRAP3200 mass spectrometer from Applied Biosystems (Darmstadt, Germany) were used with an electrospray ionization source. Epub 2008 Mar 6. Samples, which were stored at room temperature and at 5 C, were analyzed several times over a period of two weeks to demonstrate the progress of the hydrolysis of LiPF 6 in aqueous solution and commercially available electrolyte (EC/DEC (3:7 w/w) 1 M LiPF 6 ).