In-operando XAS analysis of Li-ion and Li-sulphur batteries Iztok Ar č on 1,2 Robert Dominko 3,4 , Giuliana Aquilanti 5 , Manu Patel 3,4 , Lorenzo Stievano 5 1 University of Nova Gorica, Vipavska 13, POB 301, Nova Gorica, Slovenia 2 J. Stefan Institute, Jamova 39, P. P. 3000, Ljubljana, Slovenia 3 National institute of Chemistry, P.O.B. 660, SI-1001 Ljubljana, Slovenia 4 Center of excelence Low carbon technologies, Ljubljana, Slovenia 5 Elettra Sincrotrone Trieste, Italia 6 Univeriste Montpellier II, 2 Place Eugene Bataillon–CC 1502, 34095 Montpellier (France) XAS Joint ICTP – IAEA School on novel experimental methodologies fro SR aaplications in nano-science 19. 11. 2014 Iztok Ar č on and environmental monitoring
Motivation for in-operando XAS analysis on Li-ion batteries • Searching for new cathode materials for high energy Li-ion batteries with fully reversible lithium extraction that can deliver high battery capacitiy. • Some candidates Li 2 VTiO 4 , Li 2 FeTiO 4 and Li 2 (Fe x Mn x-1 )SiO 4 • Exploiting the reversable oxidation potential of Fe 2+ /Fe 3+ , Mn 2+ /Mn 3+ / Mn 4+ and V 2+ /V 3+ /V 4+ redox couples without collapse of the structure. Theoretical specific capacity ~ 166 mAh/g ( 332 mAh/g if both Li equivalents are extracted); Thermal stable cathode materials; Cheap and environmental acceptable cathode materials; XAS 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Aim of in-operando XAS on Li-ion batteries The feasibility and reliability of in situ XANES and EXAFS analysis as a tool to monitor gradual changes of oxidation state and local structure of transition-metal cations during lithium exchange, i.e. during charging and discharging of the Li-ion battery. Provide the information on the dynamics of the battery operation on the atomic level and clarify the role of transition-metal cations (Fe, Mn, V) in the electrochemical activity of the material. Determine the degree of reversibility of the process in one or several cycles. R. Dominko, I. Ar č on, et al., Journal of Power Sources 189 (2009) 51–58 XAS 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Some basic facts about the Li 2 (Fe 0.8 Mn 0.2 )SiO 4 meterial XRD data : Advantages : Monoclinic crystal structure with P121/n1 space high capacity (200 mAh/g at a C/50 cycling rate) group. a = 8.245 Å, b = 5.018 Å and c = 8.246 Å good thermal stability The structure is composed of MnO 4 , FeO 4 , Moesbauer data on Fe valence in as synthesized SiO 4 and LiO 4 tetrahedra. Li 2 Fe 0.8 Mn 0.2 SiO 4 : •80% Fe 2+ (tetrahedral iron in crystal structure) The crystal structure contains empty octahedral •20% Fe 3+ (tetrahedral iron in crystal structure) interstitial cavities that form empty channels, which enables transport of Li + ions. 4.5 4.0 3.5 + U / V vs. Li/Li 3.0 2.5 2.0 1.5 1.0 0.0 0.2 0.4 0.6 0.8 1.0 x in Li 2-x Fe 0.8 Mn 0.2 SiO 4 Charge / discharge curves in the first cycle at C/15 current density at 60 oC. Exchanged of 1 mol Li. R. Dominko, M. Bele, M. Gaberš č ek, A. Meden, M. Remškar, and XAS J. Jamnik, Electrochem. Commun. 8 , 217 (2006). 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
In situ battery In operando XAS experiment charge / discharge owen – 60 o C Half-battery sealed in triplex foil: 3.5 Fe K-edge ELETTRA, XAFS beamline, April 2009 XANES 3.0 2.5 Mn K-edge XANES • Li 2 FeTiO 4 charging (411min), discharging (192 min) at RT 2.0 d with C/10 current density in time intervals of 25 min. 1.5 Fe EXAFS • Li 2 Fe 0.8 Mn 0.2 SiO 4 : In situ charging ( 908 min), discharging (852 min) 1.0 Mn EXAFS at 60 o C with C/15 current density in time intervals of 50 min 0.5 • XAFS beamline at ELETTRA and C beamline in HASYLAB at DESY, 0.0 Hamburg. A Si(111) double crystal monochromator with about 1 eV 6400 6800 7200 7600 8000 energy resolution at Fe k-edge (7112 eV) was used. Exact energy E (ev) calibration with simultaneous absorption measurements on a 5 mm thick Fe and Mn XANES and EXAFS spectra were V, Fe or Mn metal foil. Absolute energy reproducibility of the measured spectra was 0.05 eV. XAS measured in time intervals of of 55 min. 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Li 2-x Fe 0.8 Mn 0.2 SiO 4 battery discharging battery charging 1.6 1.6 Fe oxidation Fe reduction 1.4 1.4 as synth. 1.2 1.2 as synth. 3+ 22% Fe Normalised absorption 3+ Normalised absorption 19.5% Fe 1.0 1.0 0.8 0.8 end of reduction st cycle) (1 0.6 3+ 0.6 27% Fe st cycle) 0.4 start of reduction (1 st cycle) 0.4 end of oxidation (1 3+ 86% Fe 3+ 86% Fe 0.2 0.2 0.0 0.0 7110 7115 7120 7125 7130 7135 7140 7145 7110 7115 7120 7125 7130 7135 7140 7145 E (eV) E (eV) R. Dominko et al., Journal of The Electrochemical Society, 157 12 A1309-A1316 2010 XAS 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Li 2-x Fe 0.8 Mn 0.2 SiO 4 battery charging battery discharging Mn oxidation Mn reduction 1.6 1.6 1.4 1.4 as synth. as synth. 2+ 1.2 100% Mn 1.2 2+ 100% Mn Normalised absorption Normalised absorption 1.0 1.0 0.8 0.8 end of reduction st cycle) (1 0.6 0.6 3+ 11% Mn 0.4 st cycle) 0.4 end of oxidation (1 st cycle) start of reduction (1 3+ 37% Mn 3+ 37% Mn 0.2 0.2 0.0 0.0 6535 6540 6545 6550 6555 6560 6565 6535 6540 6545 6550 6555 6560 6565 E (eV) E (eV) R. Dominko et al., Journal of The Electrochemical Society, 157 12 A1309-A1316 2010 XAS 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Linear combination fit Li 2-x Fe 0.8 Mn 0.2 SiO 4 of XANES spectra of intermediate states with the spectra of the starting and the most charged state. 1.5 4 Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 34% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 Normalised absorption ch. 141 min Experiment 3+ 22% Fe Fit 1.0 3+ 27% Fe 3 Li 2-x Fe 0.8 Mn 0.2 SiO 4 -sint (81%) 3+ 34% Fe 0.5 Normalised absorption 3+ 35% Fe as-sint. 3+ 56% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 (19%) dis. 841 min 0.0 ch. 908 min 3+ 58% Fe 7100 7110 7120 7130 7140 7150 7160 2 E (eV) ch. 141 min 3+ 1.5 75% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 56% Fe dis. 694 min 3+ 74% Fe Normalised absorption ch. 336 min Experiment ch. 336 min 3+ 86% Fe 1.0 Fit dis. 351 min 1 Li 2-x Fe 0.8 Mn 0.2 SiO 4 (53%) ch. 908 min ch. 537 min 0.5 dis. 204 min Li 2-x Fe 0.8 Mn 0.2 SiO 4 -sint (47%) ch. 908 min 0 0.0 7100 7110 7120 7130 7140 7150 7160 7100 7110 7120 7130 7140 7150 E (eV) E (eV) R. Dominko et al., Journal of The Electrochemical Society, 157 12 A1309- XAS A1316 2010 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on
Linear combination fit Li 2-x Fe 0.8 Mn 0.2 SiO 4 of XANES spectra of intermediate states with the spectra of the starting and the most charged state. 1.5 Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 27% Fe 4 Normalised absorption dis. 841 min Li 2-x Fe 0.8 Mn 0.2 SiO 4 Experiment 1.0 Fit 3+ 22% Fe 3+ 27% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 -sint (92%) 3 3+ 34% Fe 0.5 Normalised absorption 3+ 35% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 (8%) as-sint. ch. 908 min 3+ 56% Fe dis. 841 min 0.0 3+ 58% Fe 7100 7110 7120 7130 7140 7150 7160 2 E (eV) ch. 141 min 3+ 75% Fe 1.5 dis. 694 min 3+ Li 2-x Fe 0.8 Mn 0.2 SiO 4 74% Fe 3+ 74% Fe Normalised absorption dis. 204 min ch. 336 min 3+ 86% Fe Experiment dis. 351 min Fit 1.0 1 ch. 537 min Li 2-x Fe 0.8 Mn 0.2 SiO 4 (81%) dis. 204 min ch. 908 min 0.5 ch. 908 min 0 7100 7110 7120 7130 7140 7150 Li 2-x Fe 0.8 Mn 0.2 SiO 4 -sint (19%) 0.0 E (eV) 7100 7110 7120 7130 7140 7150 7160 XAS E (eV) 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on R. Dominko et al., Journal of The Electroch. Society, 157 12 A1309-A1316 2010
Linear combination fit with XANES spectra of “as-sint.” and “ch. 908 min” Li 2-x Fe 0.8 Mn 0.2 SiO 4 1.5 Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 35% Fe Normalised absorption dis. 694 min Experiment 4 1.0 Fit Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 22% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 -sint (79%) 3+ 27% Fe 0.5 3 3+ 34% Fe Li 2-x Fe 0.8 Mn 0.2 SiO 4 (21%) Normalised absorption 3+ 35% Fe ch. 908 min 0.0 as-sint. 7100 7110 7120 7130 7140 7150 7160 3+ 56% Fe E (eV) dis. 841 min 3+ 58% Fe Linear combination fit with XANES spectra of 2 ch. 141 min 3+ 75% Fe “dis. 841 min ” and “ch. 908 min” dis. 694 min 3+ 74% Fe 1.5 Li 2-x Fe 0.8 Mn 0.2 SiO 4 3+ 35% Fe ch. 336 min Normalised absorption dis. 694 min 3+ 86% Fe dis. 351 min Experiment 1 Fit 1.0 ch. 537 min dis. 204 min Li 2-x Fe 0.8 Mn 0.2 SiO 4 (86%) dis. 841 min 0.5 ch. 908 min 0 7100 7110 7120 7130 7140 7150 Li 2-x Fe 0.8 Mn 0.2 SiO 4 (14%) 0.0 ch. 908 min E (eV) 7100 7110 7120 7130 7140 7150 7160 XAS E (eV) 19. 11. 2014 www.ung.si/~arcon/xas Iztok Ar č on R. Dominko et al., Journal of The Electroch. Society, 157 12 A1309-A1316 2010
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