All solar chargers work on the amount of power the panel (or panels) create. If you buy a 100w panel, you'd expect nominally to spend 10 hours charging a 1000w battery. If you had 10 100w panels in series, you could charge the thing in 1 hour if the battery could accept the charge that fast.
I have a160w panel and a 840w battery, I charge full in about 5 hours.