This is the extract I don't like to see though:
The A123Systems project is pursuing a second-generation nanomaterial that would replace some or all of the iron in A123 cells with manganese, increasing the battery’s energy density and therefore reducing cost per watt-hour.
For the sake of capacity gain and low initial cost this abandons the very long life potential that iron gives. Iron is by far the best of all the elements as a cathode material for lithium batteries, manganese more than half way down the scale of suitable materials.
Hopefully it will prove a dead end.
.