The next step, Pearce believes, is to add an ethical dimension to the struggle by highlighting the fact that those intitially affected will be almost entirely located in the developing world where infrastructure and resources are already at their most over-stretched.
On that crucial dimension, if lithium-ion batteries are a 3, the next best technology, NiMH is a 2, and a lead acid battery, like the one you use in your car, gets a 1.