Energy created nor destroyed.

[uniquepegasister]

Take a stick of dynamite.  Light the fuse.  Run away.  After the tremendous bang, go back and look for your stick of dynamite.

Boru

First of all that everything that comprised that stick of dynamite still exists, it's just in a different form. Matter and energy both have mass, which means if the dynamite was converted into energy, it still physically exists because energy has mass.

When you die, the chemical energy that your brain and body use simply dissipates. It is not destroyed, rather, it is passed on to the various small lifeforms that help our body decompose.
*edit*
I should add that for a bunch of so-called "critical thinkers" none of you questioned what Boru said (matter / energy cannot be created or destroyed remember), just blindly gave kudos, which shows you'll blindly follow any doctrine, as long as it's against religion...

A battery supplies energy chemically, but when a battery "dies" it can be recharged, why can't you then do the same for a human body?

I very much like the idea you have there but it's a bit on the Frankenstein side. After all thats what Frankenstein was. He was a reanimated body compromised of different parts. However, i think it would be better that the body was originally intact.