In the wake of Samsung’s recent lithium ion battery controversy, Slate takes a look at interesting place the batteries occupy in the world of modern manufacturing history.
In essence, the difference between a handy lithium battery and an incendiary one can be boiled down to three things: how industry manufactures these devices, how it integrates them into the applications they power, and how users treat their battery-containing appliances. When a lithium rechargeable discharges, lithium ions layered onto the negative electrode or anode (typically made of graphite) lose electrons, which go into an external circuit to do useful work. The ions then migrate through a conductive material known as an electrolyte (usually an organic solvent) and become lodged in spaces in the positive electrode or cathode, a layered oxide structure.
There are a variety of lithium battery chemistries, and some are more stable than others. Some, like lithium cobalt oxide, a common formula in consumer electronics, are very flammable. When such variants do ignite, the result is a blaze that can be difficult to extinguish owing to the battery’s self-contained supply of oxidant.