In the last few years most modern battery's are being recycled except for today's battery cells used in electric cars, trucks but soon they will learn how to recycle them also.
The big killer with any combustion is you just can't make it more efficient than 38% + - very little, that's as good as it gets. It doesn't matter if it super charged, turbo, diesel, gas, ethanol, propane, CNG or whatever.
Modern electric cars are 68 to 72% efficient.
And the question about burning coal, you know that the 3 coal burners in Maryland run as efficient as clean coal can run with today's technology, the scrubbers that Mirant installed 5 or 6 years ago do a amazing job cleaning the air. Nothing comes out of the old smokestacks any longer, just steam more or less from the scrubber stacks.