Because you are improperly utilising that particular battery. They have great storage, but their output is garbage. For more serious output, use other batteries. And even then, you'll still need a quality generator to provide power.

I was using the solar+nocturnal panels as well as wind turbines and funneling them into several different batteries, is using a generator any different?

Yes. Generator power output is *significantly* higher than solar and nocturn. Wind can be pretty damned good, but still nowhere near what you'll get out of Fusion and the like.

Batteries only expend power that is "needed" but if your power output is not enough to create that need, you cannot operate the machine.