How Can One Tell if a Li-Ion Battery Will Last for Decades in Only Three Weeks of Testing?
by Jeffery Dahn
Monday, May 2, 2011 | Montreal, Canada
Lithium-ion batteries are the preferred power sources for portable electronics where a calendar lifetime of three years and a charge-discharge cycle life of 500 cycles are adequate. Li-ion batteries are now targeted for EV and grid energy storage applications where thousands of cycles and lifetimes of 10 and 30 years, respectively are desired. Researchers are faced with a daunting task: How to tell in a reasonable time (i.e. in only a few weeks) if a change in an already excellent battery chemistry will further improve calendar and cycle lifetimes, bearing in mind that the loss in capacity of such cells over several weeks of testing is extremely small. In this lecture we discuss the role that precision coulometry and related measurements can play in the quest for long lifetime Li-ion cells.
Jeffrey Dahn is recognized as one of the pioneering developers of the lithium-ion battery that is now used worldwide in laptop computers and cell-phones. Dahn's recent work has concentrated on the application of Combinatorial Materials Science methods to battery and fuel cell materials problems. He is the author of over 440 refereed journal papers and co-inventor of 55 inventions with patents issued or filed.
Dahn was born in Bridgeport, Conn. in 1957 and emigrated with his family to Nova Scotia, Canada in 1970. He obtained his B.Sc. in Physics from Dalhousie University (1978) and his Ph.D. from the University of British Columbia in 1982. Dahn then worked at the National Research Council of Canada (82-85) and at Moli Energy Limited (85-90) before taking up a faculty position in the Physics Department at Simon Fraser University in 1990. He returned to Dalhousie University in 1996.
Dahn has always interacted strongly with industry. During his years at Simon Fraser University (90-96) he collaborated strongly with the R+D team at NEC/Moli Energy Canada (Now E-One/Moli Energy Canada). Dr. Dahn took up the NSERC/3M Canada Industrial Research Chair in Materials for Advanced Batteries at Dalhousie University in 1996. Dahn now interacts strongly with 3M's programs in battery materials, fuel cell materials and respirator carbons. The success of Dahn's research programs benefits from the quality his collaborators at 3M, in particular, Larry Krause, Leif Christensen, Kevin Eberman, Mark Obrovac (now at Dalhousie), Mark Debe, Radoslav Atanasoski, Lisa Croll, and Simon Smith.
Dahn has received numerous awards including: International Battery Materials Association (IBA) Research Award (1995); Herzberg Medal, Canadian Association of Physicists (1996); ECS Battery Division Research Award (1996); Fellow of the Royal Society of Canada (2001); Medal for Excellence in Teaching (2009) from the Canadian Assoc. of Physicists, The Rio-Tinto Alcan Award from the Canadian Institute of Chemistry (2010) and the "Iron Man" award from the Center Court Basketball League on his retirement from play in 2010.
A former varsity athlete (Soccer - Dalhousie University), Dahn has coached teams at all levels in both basketball and soccer. Both of Dahn's daughters were on the under-14 girls provincial championship team (2002) that Dahn coached. His son Jackson was on the 08/09 and 09/10 Sir John A. MacDonald High School Basketball team which Jeff helped coach. The team won the Nova Scotia Provincial Championship in 2010. Dahn is now head coach of that team.