I quote from skyrim wiki
"The number of charges depends on your destruction skill, and if you have a 100% destruction reduction set, many enchanted weapons will stay enchanted indefinitely."
i have 100% destruction reduction and i dont think i have noticed this? can anyone confirm?

does absorb health count as destruction? im thinking about combining that wth shock damage for an enchantment but it only has 50 charges with a black soul gem. If the above quote can be confirmed, i think i might try it.

I definitely noticed this with my shock-fire dagger when I put on fortify destruction set. I was using a dagger that ran out of charge a while ago, but it was back to doing full damage.

Yes. Absorb Health counts as destruction.

Makes me want to try enchanting a bow with 100% destruction cost via console commands to see if it'd give me infinite charges.

They placed the slider control there for a reason ...