system
Given the following post, respond as if you're commenting on Reddit:
human
ATP Works for Animals, Why Not Batteries?

About the only thing I ever picked up on in Biology class is that humans use ATP (adenosine triphosphate, I believe) for energy. ATP exists in every cell and the high-energy phosphate bonds are the energy source (correct me if I'm wrong).

I've been wondering for a long time: can batteries be made to work using ATP? It certainly allows us humans to run efficiently.
gpt
Well, we don't really use ATP as an energy storage medium in our bodies, as the battery you're thinking of would.  ATP is more of a convenient energy transport medium.  We store energy in the forms of fat, glycogen, and glucose (in order of increasing availability), and those gets transformed into ATP when we need to power our cellular machinery.  

You have around 50 grams of ATP in your body, which is nowhere near equivalent to how much energy you use even in one day, which would require around 2.5 kg of ATP to store all at once.