The chances are that the portable gadgets in your bag or pocket use lithium-ion batteries (LIBs) as they are among the most popular types of rechargeable batteries for consumer electronics.  LIBs have been commercially available since 1991, but the technology, which involves the movement of lithium ions from the negative electrode to the positive electrode during discharge and back when charging, has been around since the 1970s.  As well as reviewing the evolution of LIBs over the years, including their pros and cons, this seminar examines new opportunities and research, especially those related to electric vehicles and energy storage.