To charge an 80Ah battery at 12V, you need 960Wh, or 1kWh. A 200W solar panel can provide this in 5 hours of sunlight. Next, account for. What size solar panel to charge 80ah battery? Enter battery specs (ah, volts, and battery type), charge controller type, and desired charge time in our solar panel size calculator to find out. Many people are looking to harness solar power for their energy needs, but figuring out the right equipment can be tricky. Imagine you're planning a weekend getaway in your RV or need backup power for your. Recharging an 80ah battery using solar panels is straightforward, but how long does it take? And how many panels do you need and what size? We will answer those questions and related topics in this guide using simple teems and concepts. Charging duration is contingent on solar panel output, 2.