Lithium batteries: a look into the future. Bruno Scrosati Department of Chemistry, University of Rome “Sapienza”

To fight the global warming a large diffusion in the road of low emission vehicles (HEVs) or no emission vehicles (EVs) is now mandatory

Electrified Vehicle sales forecast for Asia Pacific countries Source: The Korean Times

Source: http://aspoitalia. blogspot

Will it be a tank of lithium to drive our next car? Key requisite: availability of suitable energy storage, power sources Best candidates: lithium batteries

Courtesy of Dr. Jürgen Deberitz CHEMETALL GmbH Where lithium is taking us? Courtesy of Dr. Jürgen Deberitz CHEMETALL GmbH

Li-ion battery system: a scheme of operation Electrochemical Reactions Cathode Anode Overall Cathode more positive redox potential Discharge: Li+ intercalates the positive materials -> provide outer electron flow Charge: Li+ deintercalates from cathode and intercalates the anode. Li-ion shuttles b/w cathode and anode during cycling -> conversion & storage of electrochemical energy within the Cells Energy density: storage of large amount of Li Power density: fast ionic/electronic transfer The present Li-ion batteries rely on intercalation chemistry! (From: K. Xu, Encyclopedia of Power Sources, Elsevier, 2010) 7 7

Lithium Batteries Although lithium batteries are established commercial products Further R&D is still required to improve their performance especially in terms of energy density to meet the HEV, PHEV, EV requirement Jumps in performance require the renewal of the present lithium ion battery chemistry, this involving all the components, i.e., anode, cathode and electrolyte

Energy Density (Wh/kg)  EV driving range (km) THE ENERGY ISSUE Energy Density (Wh/kg)  EV driving range (km) Middle size car (about 1,100 kg)  using presently available lithium batteries (150 Wh/kg)  driving 250 km with a single charge   200 kg batteries Enhancement of about 2-3 times in energy density is needed!

Electric Vehicle Applications- The energy issue 140 Wh/kg* 170 Wh/kg* 200 Wh/kg* Estimated progress of the conventional Lithium-Ion Technology in terms of battery weight in EVs 200kg 140 kg Li-ion Batteries Present Near future Modified by courtesy of Dr. Stefano Passerini, Munster University, Germany 10

Midterm evolution of the lithium ion battery technology Some examples of new-concept batteries developed our laboratory.

Ente Nazionale Idrocarburi ENI SpA Main goal: complete the development of the battery starting from a further optimization of the electrode and electrolyte materials, to continue with their scaling up to large quantities and then on their utilization for the fabrication and test of high capacity battery cells, to end with the definition and application of their recycling process. Collaborative participation of nine partners. Consorzio Sapienza Innovazione (CSI), Italy, managing coordinator HydroEco Center at Sapienza including Dept Chemistry (scientific coordinator) , Dept Physics, Universities Camerino and Chieti; Chalmers University of Technology Ente Nazionale Idrocarburi ENI SpA Chemetall Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) SAES Getters SpA ETC Battery and Fuel Cells Sweden AB Stena Metall AB.

The APPLES SnC/ GPE / LiNi0.5Mn1.5O4 lithium ion polymer battery anode GPE cathode http://www.applesproject.eu

The Li[Ni0.45Co0.1Mn1.45]O4 / SnC lithium ion cell J.Hassoun, K-S. Lee, Y-K.Sun,B.Scrosati, JACS 133 (2011)3139

The Li[Ni0.45Co0.1Mn1.45]O4 / SnC lithium ion battery Li[Ni0.45Co0.1Mn1.45]O4 + SnC  Li (1-x)[Ni0.45Co0.1Mn1.45]O4 + LixSnC Projected energy density: 170 Wh/kg

Li4Ti5O12 / Li[Ni0.45Co0.1Mn1.45]O4 lithium ion battery   H-Gi Jung, M. W. Jang, J. Hassoun, Y-K. Sun, B. Scrosati, Nature Communications, 2 (2011) 516

Li4Ti5O12 / Li[Ni0.45Co0.1Mn1.45]O4 lithium ion battery Li4Ti5O12 + Li[Ni0.45Co0.1Mn1.45]O4  Li4+xTi5O12 + Li (1-x) [Ni0.45Co0.1Mn1.45]O4 Projected energy density: 200 Wh/kg

Electric Vehicle Applications- The energy issue Revolutionary Technology- Change >500 Wh/kg Super- Battery < 100kg 140 Wh/kg* 170 Wh/kg* 200 Wh/kg* Estimated limit of Lithium-Ion Technology 250 kg 140 kg Li-ion Batteries Year Present 2012 2017 Modified by courtesy of Dr. Stefano Passerini, Munster University, Germany 18

Cathode side: Li Metal Chemistries Where should we go ? 1 2 3 4 5 6 250 500 750 1000 1250 1500 1750 4000 3750 Potential vs. Li/Li+ Capacity / Ah kg-1 Li metal O2 (Li2O) F2 S O2 (Li2O2) Lithium-Element Battery Cathodes Li-Ion Oxide Cathodes "4V" Intercalation chemistry Carbon anodes Modified by courtesy of Dr. Stefano Passerini, Munster University, Germany

< Theoretical capacity of lithium polysulfides > The lithium-sulfur battery < Theoretical capacity of lithium polysulfides > Anodic rxn.: 2Li → 2Li+ + 2e- Cathodic rxn.: S + 2e - → S2- Overall rxn.: 2Li + S → Li2S, ΔG = - 439.084kJ/mol OCV: 2.23V Theoretical capacity : 1675mAh/g-sulfur Li2S8 : 209 mAh/g-S, Li2S4 : 418 mAh/g-S Li2S2 : 840 mAh/g-S, Li2S : 1675 mAh/g-S Cobalt: 42,000 US$/ton Sulfur: 30 US$/ton Charge process Discharge process S8 Li2S8 Li2S6 Li2S4 Li2S2 Li2S Lithium Sulfur Li Li+ Li2S Li+ + S e- Electrolyte (polymer or liquid) Anode Cathode B. Scrosati, J. Hassoun, Y-K Sun, Energy & Environmental Science, 2011

The lithium-sulfur battery Major Issues:  solubility of the polysulphides LixSy in the electrolyte (loss of active mass  low utilization of the sulphur cathode and in severe capacity decay upon cycling)  low electronic conductivity of S , Li2S and intermediate Li-S products (low rate capability, isolated active material)  Reactivity of the lithium metal anode (dendrite deposition, cell shorting, safety)

The lithium-sulfur battery Sleeping for long time……. booming in the most recent years………… Ji, X., Lee, K.T., Nazar, L.F., Nat. Mater 8, 500 (2009) Lai, C. Gao, X.P., Zhang, B., Yan, T.Y., Zhou, Z J. Phys. Chem. C 113, 4712 (2009). Ji, X., L.F. Nazar, J. Mat. Chem, ., 20, 9821 (2010) Ji, X., S. Ever, R. Black, L.F. Nazar, Nat. Comm., 2, 325 (2011) N. Jayprakash,J. Shen, S.S. Morganty, A. Corona, L.A. Archer, Angew. Chemie Intern. Ed. 50, 5904 (2011) E.J. Cairns et al, JACS, doi.org/10.1021/ja206955k and others ……. however mainly focused on the optimization of the sulfur cathode still keeping Li metal anode

Our approach: SnC nanocomposite / gel electrolyte/ Li2S-C cathode sulfur lithium-ion polymer battery ANODE Conventional :Li metal  our work : Sn-C nanocomposite (gain in reliability and in cycle life) ELECTROLYTE Conventional : liquid organic  our work : gel-polymer membrane (gain in safety and cell fabrication) CATHODE Conventional : sulfur-carbon  our work : C- Li2S composite Conventional : liquid organic (Li-metal-free battery ) (Li metal battery) Jusef Hassoun and Bruno Scrosati, Angew. Chem. Int. Ed. 2010, 49, 2371

SnC/ Li2S lithium ion battery J. Hassoun & B. Scrosati, Angew. Chem. Int. Ed. 2010, 49, 2371

THE CATHODE Potentiodynamic Cycling with Galvanostatic Acceleration, PGCA, response in the CPGE. Li counter and reference electrode. Room temperature. In situ XRD analysis run on a Li/CGPE/Li2S cell at various stages of the Li2S → S+ 2Li charge process. Anode peak area = cathode peak area (integration) Reversibility of the overall electrochemical reaction! Jusef Hassoun, Yang-Kook Sun and Bruno Scrosati, J. Power Sources, 196 (2011) 343

SnC/ Li2S lithium ion polymer battery SnC+ 2.2Li2S  Li4.4SnC+ 2.2S Projected energy density: 400 Wh/kg Safety

The kinetics issue Capacity decay upon rate increase. Slow kinetics! Some Li2S particles remain uncoated by carbon Optimization of the cathode material morphology is needed. Work in progress in our laboratories

Improved sulfur-based cathode morphology Hard carbon spherule-sulfur (HCS-S) electrode morphology, showing the homogeneous dispersion of the sulfur particles in the bulk and over the surface of the HCS particles. The top right image illustrates the sample morphology as derived from the SEM image (top left) and the EDX image (bottom right) in which the green spots represent the sulfur J.Hassoun, J. Kim, D-J. Lee, H.-Gi.Jung,S-M.Lee,Y-K.Sun, B. Scrosati, J.Power Sources, Doi:10.1016/jpowsour.2011.11.60 

Improved sulfur-based cathode morphology Rate capability Cycling response room temperature 0  C J.Hassoun, J. Kim, D-J. Lee, H.-Gi.Jung,S-M.Lee,Y-K.Sun, B. Scrosati, J.Power Sources, Doi:10.1016/jpowsour.2011.11.60 

LiSiC/ S-C lithium ion battery J.Hassoun, J. Kim, D-J. Lee, H.-Gi.Jung,S-M.Lee,Y-K.Sun, B. Scrosati, J.Power Sources, Doi:10.1016/jpowsour.2011.11.60 

LiSiC/ S-C lithium ion battery Projected energy density: 400 Wh/kg

The lithium-air battery. The ultimate dream Potential store 5-10 times more energy than today best systems Two battery versions under investigation Lithium-air battery with protected lithium metal anode and/or protected cathode (aqueous electrolyte) 2Li + ½ O2 + H2O 2LiOH Theor. energy density : 5,800 Wh/kg Lithium-air battery with unprotected lithium metal anode (non aqueous electrolyte) Li + ½ O2  ½ Li2O2 Theor. energy density : 11,420 Wh/kg Present Lithium Ion technology (C-LiCoO2: Theor energy density: 420 Wh/kg

The lithium-air battery (organic electrolyte) Unprotected electrode design Organic electrolytes Remaining issues: high voltage hysteresis loop, limited cycle life, stability of the organic electrolytes, reactivity of the lithium metal anode….. Courtesy of Prof O.Yamamoto, Mie University, Japan

Li / Polymer electrolyte / SP,O2 cell study by PCGA Oxygen electrochemistry in the polymer electrolyte lithium cell at RT Li / Polymer electrolyte / SP,O2 cell study by PCGA Y-C. Lu, Z. Xu, H.A. Gasteiger, S. Chen, K. Hamad-Schifferli, Y. Shao-Horn, 2010, JACS, 132, 12170-12171 Y-C. Lu, H.A. Gasteiger, Y. Shao-Horn, Electrochem Solid State Lett , 2011, 14, A70-A74 Lithium superoxide formation Lithium peroxide formation Lithium oxide formation Very low charge -discharge hysteresis with efficiency approaching 90% ! Reaction mechanism J. Hassoun, F. Croce, M. Armand & B. Scrosati, Angew. Chem. Int. Ed., 2011, 50, 2999

Oxygen electrochemistry in the polymer electrolyte lithium cell at RT Electrolyte decomposition ! EC:DMC, LiPF6 P.G. Bruce et al., IMLB, Montreal, Canada, June 27-July 2, 2010 P.G. Bruce et al., ECS, Montreal, Canada, May 01-06, 2011 J. Hassoun, F. Croce, M. Armand & B. Scrosati, Angew. Chem. Int. Ed., 2011, 50, 2999

Oxygen electrochemistry in the polymer electrolyte lithium cell at RT Reduction products Li / polymer electrolyte / SP,O2 galvanostatic discharge XRD of the SP electrode

The last concern: are lithium metal reserves sufficient for allowing large electric vehicle production?

Main Lithium Deposits

B.Scrosati, Nature, 473 (2011) 448

LAB-FCT Laboratory structure Principal investigator: Prof Stefania Panero Researchers: Jusef Hassoun Maria Assunta Navarra Priscilla Reale Post Docs: Sergio Brutti Inchul Hong Graduate students: average 3 Visitors : average 2 Master students : average 4 Total : average 15

ACKNOWLEDGEMENT This work was in part performed within the 7th Framework European Project APPLES (Advanced, Performance, Polymer Lithium batteries for Electrochemical Storage )