A provocatively bearish piece in today’s Times argues based on some Japanese researchers’ work that lithium ion batteries are fundamentally unsafe at any speed. While it’s not news to say that lithium ion batteries are volatile things, it is worth noting the argument that they are more dangerous than manufacturers want to know.
The recent recalls at Sony, Sanyo and Matsushita have, indeed, arisen from problems during the manufacturing process that led to short-circuits and other overheating issues, but it is possible, Tokyo Institute of Technology researchers say, to produce a lithium-ion battery that poses no fire risk, even if a fault develops. Existing lithium-ion batteries submerge the electrodes in an organic solvent that acts as the electrolyte, and separates them with a film of perforated plastic, which is expensive to produce. An alternative, chemical engineers argue, is to encase the electrodes in a solid polymer electrolyte â€“ a structure that might have to be heated slightly to ensure good function.