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Energy Storage


Li ion battery has had a huge impact in technology today. We have over the years worked on several aspects of battery, focusing particularly on Li ion systems. Creation of new designs for battery, improving the energy capacity of electrode materials, improving stability and cycling, creation of 3D nanostructured systems for thin film battery, creation of organic (green) electrodes are some of the results we have reported. Our ongoing work captures all these aspects of Li ion battery and we are constantly thinking about new formats for electrochemical energy storage in addition to the Li ion battery.


Electric double layer capacitors (and pseudo capacitors) form the class of supercapacitors, which are also electrochemical energy storage devices but with different characteristics than battery. While the energy density of supercapacitors are much smaller than that of battery, the power density can be orders of magnitude higher because they can be charged and discharged very fast. Carbon materials are typically used as electrodes in electric double layer capacitors whereas oxides and other electrode materials give pseudo-capacitance. We have worked on various materials over the years to develop better supercapacitors, with better temperature stability and with new designs that offer better form factor. Three dimensional, nanostructured electrode materials are being developed for the next generation of supercapacitor electrodes.


S. Yang, Y. Gong, Z. Liu, L. Zhan, D. P. Hashim, L. Ma, R. Vajtai, P. M. Ajayan, Bottom-Up Approach Toward Single-Crystalline VO2-Graphene Ribbons as Cathodes for Ultrafast Lithium Storage. Nano Letters 13, 1596-1601 (2013). Read Article

R.S. Borges, A. L. M. Reddy, M. T. F. Rodrigues, H. Gullapalli, K. Balakrishnan, G.G. Silva, P. M. Ajayan, Supercapacitor Operating At 200 Degrees Celsius. Scientific Reports 3 (2013). Read Article

A. L. M Reddy, S. Nagarajan, P. Chumyim, S. R. Gowda, P. Pradhan, S. R. Jadhav, M. Dubey, G. John, P. M. Ajayan, Lithium storage mechanisms in purpurin based organic lithium ion battery electrodes. Scientific Reports, 2 (2012). Read Article

S. R. Gowda, V. Pushparaj, S. Herle, G. Girishkumar, J. G. Gordon, H. Gullapalli, X. Zhan, P. M. Ajayan, A. L. M. Reddy, Three-Dimensionally Engineered Porous Silicon Electrodes for Li Ion Batteries. Nano Letters 12, 6060-6065 (2012). Read Article

N. Singh, C. Galande, A. Miranda, A. Mathkar, W. Gao, A. L. M. Reddy, A. Vlad, P. M. Ajayan, Paintable Battery. Scientific Reports 2 (2012). Read Article

J. J. Yoo, K. Balakrishnan, J. Huang, V. Meunier, B. G. Sumpter, A. Srivastava, M. Conway, A. L. M. Reddy, J. Yu, R. Vajtai, P. M. Ajayan, Ultrathin Planar Graphene Supercapacitors. Nano Letters 11, 1423-1427 (2011). Read Article

W. Gao, N. Singh, L. Song, Z. Liu, A. L. M. Reddy, L. Ci, R. Vajtai, Q. Zhang, B. Wei, P. M. Ajayan, Direct Laser Writing of Micro-Supercapacitors on Hydrated Graphite Oxide Films. Nature Nanotechnology, 6 (2011). Read Article

A. L. M. Reddy, M. M. Shaijumon, S. R. Gowda, P. M. Ajayan, Multisegmented Au-MnO2/Carbon Nanotube Hybrid Coaxial Arrays for High-Power Supercapacitor Applications. Journal of Physical Chemistry 114, 658-663 (2010). Read Article

A. L. M. Reddy, A. Srivastava, S. R. Gowda, H. Gullapalli, M. Dubey, P. M. Ajayan, Synthesis Of Nitrogen-Doped Graphene Films For Lithium Battery Application. ACS Nano 4, 6337-6342 (2010). Read Article

A. L. M. Reddy, M. M. Shaijumon, S. R. Gowda, P. M. Ajayan, Coaxial MnO2/Carbon Nanotube array Electrodes for High-Performance Lithium Batteries. Nano Letters 9, 1002-1006 (2009). Read Article