I have a 12ah Weize lithium running a 93SV and black box. I typically only fish for a few hours at a time and I haven't ran it dead yet.

The black box will draw power when connected so you will need a disconnect switch of some sort, especially when running smaller batteries.

I strongly prefer lithium for the LS setup because the voltage stays pretty consistent in the mid-high 12s. Performance starts to degrade once they start dipping below 12v from what I have seen.