Ion Conducting Glasses: An Overview of Our Activities at IIT Bombay

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1 Department of Metallurgical Engg. and Materials Sci Indian Institute of Technology - Bombay, India ajit.kulkarni@iitb.ac.in 1/26 Ion Conducting Glasses: An Overview of Our Activities at IIT Bombay A. R. Kulkarni

2 2/26 Today s presentation Lithium Ion Conductivity in Al(PO 3 ) 3 Glasses Electrical and Mechanical relaxations Mixed Mobile Ion Cross-over Effect : Through relaxations Complete Conductivity spectrum at room temperature 2. Applications of Glassy Compositions Investigated Fluoride Ion Selective Electrode Glass and Glass Ceramics for substrate applications LATP Glass Ceramics for Lithium micro-batteries 3. What next? Collaboration Possibilities Structure and ion dynamics glasses through NMR? Lithium microbatteries using PLD more collaborations

3 LiF-Li 2 O- Al (PO 3 ) 3 glasses 3/26 Kulkarni, Maiti Solid State Ionics 14(1984) 319

4 High Conductivity and Mechanical Loss Due to F - ions in PbF 2 -MnF 2 -Al(PO 3 ) 3 Glasses Kulkarni, Angell Mat Res bull 21(1986) /26

5 Electrical Conductivity of LiF-PbF 2 -Al(PO 3 ) 3 Glasses Interest: Study mixture and cross over from dominant cation to dominant anion (Mixed mobile ion effect)? Kulkarni, Angell J, Non Cryst Solids 99(1988)195 5/26

6 Mechanical Relaxation Behaviour to Confirm the Mixed Mobile Ion Effect 6/26

7 7/26 Mixed Alkali Effect Mixing two alkali glasses (SiO 2, B 2 O 3, P 2 O 5 ) Two Different Mobile cations one glass former Two Different ions Li + - F - : anion - cation Single cation Two Different Glass Formers New term Mixed Mobile Ion Effect Can it be observed in the ac conductivity?

8 Scaling Behavior in the Frequency Dependent Conductivity of Mixed Alkali Glasses Kulkarni, Lunkenheimer, Loidl, Solid State Ionics 112(1998)69 8/26

9 Conductivity Spectroscopy Covers large frequency range > 17 decades ( Hz) Allows study of the motion of charged particles on very different time scales 9/26

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11 A Complete Conductivity Spectrum 11/26 Kulkarni, Lunkenheimer, Loidl, Ceramics Trans 92(1999)115 Translational mode Vibration mode

12 Fluoride Ion Selective Electrode To develop a fluoride glass with enhanced ion conduction Design and fabricate a prototype fluoride ion selective electrode MATERIALS FOR ISE S LaF 3 single crystal (commercially used) Deposition of Metal fluorides on Metals Fluoride Polymer composites GLASS ELECTRODES VERSATILE FOR HYDROGEN IONS High cost Limited Shelf life (6 months) NEW GLASS ELECTRODES FOR FLUORIDE IS ENVISAGED TO BE SIMILAR 12/26

13 13/26 Conductivity (S/cm) 10-4 B D 10-5 C A E F / T (K -1 ) Longer shelf life Inexpensive than commercial

14 Glass Based Low Temperature Co-Fired Ceramic (LTCC) Substrates for Electronic Packaging Materials Glass ceramics Glass + ceramic Crystallizable glass + ceramic 14/26

15 Ca-Al-BSG (Anorthite) Glass Anorthite(CaO.Al 2 O 3.2SiO 2 ) C:A:S = 1:1.82:2.14 Liquidus temperature >1500 o C Isothermal contours indicate liquidus Reduction in liquidus Increasing SiO 2 Increasing CaO Selected composition C:A:S = 1:1.33:3.13 Liq. Temp o C; Batch size 100g 15/26

16 Ca-Al-BSG (Anorthite) glass Composition Properties Component wt% SiO 2 47% B 2 O 3 15% Al 2 O 3 20% CaO 15% PbO 3% Property Value T o g C 680 T o s C 740 α ppm/ o C ( o C) 4.7 ε 7.9 tan The glass has required dielectric and thermal properties for LTCC C. J. Dileep Kumar et al., J. Am. Ceram. Soc., 91 [2], , (2008) 16/26

17 Softening behaviour of glass Initial stage at RT Sintering Smoothening Rounding Bead formation Bead on alumina without flow 17/26

18 Wetting and flow of over fillers Flow over alumina Poor flow over fused silica Flow over mullite Flow over cordierite C. J Dileep Kumar et al., J. Am. Ceram. Soc., 92 [3], , (2009) 18/26

19 Tape casting of Anorthite Glass+Cordierite Tape casting slurry Constituent Content wt% Powder Solvent (Ethanol+xylene) Dispersant (MFO) 0.55 Binder (PVB) 3.24 Plasticizer (PEG+BBP) 2.49 LTCC green tape Cross-section of cofired LTCC substrate 19/26

20 LATP Glass Ceramic as Electrolyte for Lithium Microbattery Lithium Battery at Present Lithium Battery in Future Thin Film Technology Anode Solid Electrolyte Li4.4Sn LVSO glass LiCoO2 EC/PC-LiPF6 LiC6 Cathode LiCoO 2 Explosion of Lithium Battery (Organic Liquid Electrolyte) Smart-Card LSI TFB loop antena On Chip Battery Silicon LSI 20/26

21 Construction of Thin Film Lithium Ion Battery 1. Amorphous junction 2. Only by PLD Pt current collector SnO anode (400 nm) (10 nm) Li 2 O-V 2 O 5 -SiO 2 solid electrolyte (1-2 µm) (< 1 mm) Including substrate Crystal-crystal junction Crystal-amorphous junction LiCoO 2 cathode Pt/Cr current collector SiO 2 substrate (500 nm) (10 nm) Schematic cross-sectional view of a thin-film lithium-ion battery. 21/26

22 Heat treatment schedule As cast glass T = 550 o C > (Tg o C) t = 6,12, 24 hr t = 6 hr T = 550, 650, 750, 850 o C, 900 o C, 950 o C Soman et al Journal of Solid State Electrochemistry (2012) 22/26

23 Pulse Laser Deposited LATP Glass Ceramic Film (a) Thin film battery structure with LATP film (b) I-V Characteristic (c) Substrate : Pt/SiO 2,Target : Glass Ceramic optimized at 850 o C, 6 hr, Laser : ArFexcimerlaser (Coherent COMPexPro102), Wavelength : 193 nm; Energy: 150 mj (a) (b) (c) 23/26

24 What Next? - Possibilities To identify suitable anode and cathode materials that are stable with LATP glass ceramics to fabricate microbatteries and evaluate performance Structural studies through NMR and other spectroscopic studies to support of observations from conductivity data and structural hierarchy New glassy systems and ion dynamics 24/26

25 All those who made it possible. Dr. H. S. Maiti and Prof. A. Paul (graduate supervisors at IIT) Prof. C. A. Angell, During Post Doc at Purdue University Prof. Loidl and Dr. Lunkenheimer at University of Augsburg, Germany during Humboldt Fellowship Prof. Junichi Kawamura at IMRAM Japan, INDO-JAPAN Project on microbatteries My colleagues, undergraduate and graduate students at IIT Bombay Collaborators at National Institutes and Laboratories National Funding Agencies IFCPAR and CEFIPRA for this and future opportunities 25/26

26 Thank you from SMDL Sensor Materials and Devices Laboratory Dept. of Metallurgical Engineering and Materials Science, IIT Bombay 26/26