Lithium Ion: Unsafe at Any Charge

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 – a structure that might have to be heated slightly to ensure good function.


  1. It’s hilarious to find a battery ad under this post :-)

  2. Terry Foecke says:

    The lithium ion polymer (LiPON) batteries can have the same problems with “spontaneous catastrophic disassembly” as LiON batteries, but it depends on the materials used and design. Some are very, very stable in the recharge cycle, which is where the problems are.
    What is possibly useful as an investing angle is that LiPON batteries use most of the technologies like vapor-phase deposition and fine-line etching that are needed already all over the high-tech manufacturing industry. But kicked up a notch, because the materials must be deposited as funky alloys, with very narrow tolerances for the exact composition. Tricky is putting it mildly, and expensive, but encouraging to have something as important as portable energy storage building on such a solid base. Much better than micro fuel cells, for example.

  3. John Phostec says:

    lithium ion batteries are fundamentally unsafe!