That charge controller you have is the weak link in your system. Renogy panels are highly rated, but that charge controller is part of a $25 cheap chinesium kit. You can get them individually for like $5 USD

What kind of 12v batts are you running? I assume deep cycle marines, since that's the type you want for solar but you never know. I know they're expensive as frig, but maybe look into lithium banks when you upgrade?