Lithium-Oxygen Batteries –The next

generation of energy storage technology

By Richard Padbury

Principle Investigator: Dr. Xiangwu Zhang

Why Energy Storage?

• Consumer Products

Why Energy Storage?• Energy Demand and Climate Change - World energy demand

expected to double by 2050

IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the

Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)].

Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

World Energy Technology Outlook – 2050. EUROPEAN COMMISSION

Directorate-General for Research

Investment in Renewable EnergyConsumption and production must be

exactly equal all the time.

‘. .

• The effective utilization of renewable energy

sources

• Improving the performance of consumer

products

The advancement of energy storage

technologies is essential for:

Existing and Emerging Energy Storage Technologies –

Comparison of theoretical energy densities

Figure obtained from: R. Padbury, X. Zhang. Journal of Power Sources 196 (2011) 4436–4444

Limitations

• Structure

• Reaction Kinetics

• Internal resistance

What is a Lithium-Oxygen Battery?

Anode half cell reaction

Li2 + e- Li+

Cathode half cell reaction

O2+2Li++2e- Li2O2

Overall Reaction

2Li + O2 → Li2O2 - 3.1 v

OIL RIG

Figure obtained from: R. Padbury, X. Zhang / Journal of Power Sources 196 (2011) 4436–4444

What Limits the Li-O2 Battery?

Figure obtained from: R. Padbury, X. Zhang . Journal of Power Sources 196 (2011) 4436–4444

Reaction kinetics are related to internal resistance

• High porosity

• Large surface area to volume ratio

• Lighter material weight

How textiles can improve the performance of

the Li-O2 battery

• High Porosity – Facilitate O2 diffusion and reduction product

deposition during discharge

Figure obtained from: J.P. Zheng, P. Andrei, M. Hendrickson, E.J. Plichta, J. Electrochem. Soc. 158 (2011)

A43–A46

How textiles can improve the performance of

the Li-O2 battery

Electrospun carbon nanofibers (CNF’s)

SEM micrograph obtained from: Liwen Ji and Xiangwu Zhang. Nanotechnology 20 (2009) 155705 (7pp)

Research Objective

Maintain good electronic conductivity while

promoting ionic conductivity at the cathode:

• Increase reaction kinetics - achieve higher

discharge capacities

• Create a more uniform concentration of

reactants inside the cathode

Composite CNF’s

• Disperse inorganic particles in PAN

solution

• Electrospin to form non-woven mat

• heat treat to form carbon nanofiber

composites

SEM micrograph obtained from: Liwen Ji, Xiangwu

Zhang. Electrochemistry Communications 11 (2009)

1146–1149

Industry Relevance

• IBM Battery 500 Project

• Polyplus Battery Company

Research and development of Li-O2

Battery• Anode

– Stable to moisture

• Cathode– Meso - porosity

– High oxygen diffusivity

– High Li+ conductivity

– High electrical conductivity

• Electrolyte– High oxygen and Li+ solubility

– High oxygen and Li+ diffusivity

– Hydrophobic

• Catalyst– Facilitate charge and discharge

reaction

High

Performance!

AcknowledgementsPrinciple Investigators:

Dr. Xiangwu Zhang

Dr Behnam Pourdeyhimi

Special Thanks:

Dr. Mataz Alcoutlabi, Dr. Zhan Lin, Dr. Quan Shi, Hun

Lee, Guanjie Xu, Yingfang Yao, Ozan Toprakci, Shuli

Li, Ying Li, Shu Zhang, Bohyung Kim, Narenden

Vitchuli, Michael Sieber, Sarah Hoit and Andrew

Hicks

Practical Energy Densities

Figure obtained from:J.S. Hummelshøj, J. Blomqvist, S. Datta, T. Vegge, J. Rossmeisl, K.S. Thygesen, A.C. Luntz, K.W. Jacobsen, J.K.

Norskov, J. Chem. Phys. 132 (2010) 071101

Practical Energy Densities

Lithium-Oxygen Battery The Internal Combustion Engine

Theoretical Energy Density ~ 13 kwh/kg Theoretical Energy Density ~ 13.2 kwh/kg

Energy efficiency ~ 50% Energy efficiency ~ 12%

Practical Energy Density ~ 6.5 kwh/kg Practical Energy Density ~ 1.5 kwh/kg

But, Li-O2 battery is further limited by bulky

components

Best approximation is 1.7 - 2.5 kwh/kg

Practical Energy Density = Efficiency x Theoretical Energy Density