For the sake of argument, suppose storing death didn't keep you "alive", but rather- stopped your body on a cellular level from "dying"?
If anyone's seen "Torchwood", I'm basically referring to that bland of logic...
This has been referred to broadly in other peoples suggestions, so I'll try and be as simple as possible... .3.;
So, technically speaking- "death" occurs when all your cells stop respiring (to create energy to make more cells, etc), so using stored death would stop your body on a cellular level from working, even with the right components. Suppose then, that storing "Death" would cause your cells to function, even without the right components. So, that would mean your cells could still function without having to respire to create energy (and when using the stored metal, your cells would stop functioning). The cool thing about this would be that you wouldn't need to breath- as you wouldn't require oxygen for respiration- the same would apply for eating and drinking. You also wouldn't need blood (to an extent), as blood mostly carries around that oxygen (but blood also carries a bunch of other useful stuff like hormones, so that could only work in the short term). Obviously, your brain and nervous system aren't affected by the change, you'll still feel pain (but your body won't rot), and if your brain is severed somehow (or your muscles rip, or something...)- you won't be able to use them. Storing death only means that your Cells won't need to live off anything, so there are a variety of bodily functions that would be not needed (specifically revolving around distributing stuff to the cells).
This is purely speculation, of course (it would probably make more sense for storing health, I guess... .3.- and doesn't really rely on any evidence, so I may be completely wrong. I'd appreciate being corrected :3