February 3, 2012

Colloquium Speaker: Rengaswamy Srinivasan


 

Rengaswamy Srinivasan, PhD, has been a Senior Professional Staff scientist at the Johns Hopkins University Applied Physics Laboratory since 1989.  His previous appointments include Lecturer at the Indian Institute of Technology (IIT) Bombay, Research Associate at Georgetown University, Washington, DC, and Research Scientist at the Johns Hopkins University. He completed graduate studies in 1978 in Chemistry at the Indian Institute of Science, Bangalore.

 Dr. Srinivasan's passion for electrochemistry sparked from a childhood interaction with the Central Electrochemical Research Institute in India. Since joining APL, Dr. Srinivasan has authored over 50 papers and 9 US and International Patents.  He has been an invited speaker in meetings held by US Federal agencies and professional societies. His postdoctoral trainees have continued into various electrochemistry-related fields including batteries, corrosion, fuel cells, fractal electrodes, nanoscience and electroanalytical chemistry.




Colloquium Topic: Advanced Lithium Batteries: One way to use, many ways to abuse

 

In 1991, SONY made the first rechargeable lithium battery, propelling a revolution in mobile devices. The following twenty years in lithium battery development witnessed substantial gains in energy density and power delivery for ever-more-complex personal electronics.  Despite these advances in performance, lithium batteries continue to suffer a safety profile that includes rare-but-catastrophic failure, with batteries infrequently catching fire during routine use. Emerging interest in lithium batteries for mainstream use in hybrid and electric vehicles highlights the need for new strategies to minimize or eliminate the risk of catastrophic failure in an application where requirements for robustness and safety are higher than with personal electronics.

 The Achilles heel in present-day lithium batteries are nanometer-thick protective layers that are coated onto the anode and cathode. When these protective layers fail, a battery is doomed to blowout, despite auxiliary safety measures like mechanical and chemical fuses. In this talk, we present a new technology, recently developed at the Johns Hopkins University Applied Physics Laboratory, that directly monitors the health of these protective layers.  With an eye towards inexpensive and miniature design, this emerging technology may be able to detect evolving threats in cells of most batteries, triggering countermeasures that avoid blowouts entirely.