While the exact cause of the recent fires experienced with Samsung’s Galaxy Note 7 smartphones have not yet been precisely determined, it appears that these incidents are in some way related to the batteries.
One known problem for both the lithium-ion (Li-ion) batteries used in today’s mobile phones as well as next-generation lithium metal batteries is that they are susceptible to the growth of finger-like deposits of lithium called dendrites inside the battery. These dendrites grow so long that they pierce the barrier between the two sides of the battery and cause a short circuit, possibly leading to a fire.
Now researchers at the University of Michigan—inspired by the potential of next-generation lithium metal batteries to store 10 times more charge than conventional Li-ion batteries—have peered into lithium metal batteries to observe the growth of dendrites. They leveraged a novel microscopy tool that enables them to watch how the lithium changes inside the battery during cycling to create conditions conducive to dendrite growth.