Hello solar forum, I don't often post in here! My shed has had solar power for the last 2 years. It has a 120W solar panel, PWM charge controller (see pic below) and a 105aH non-sealed deep cycle battery. I have not been looking after the battery properly and let the levels get too low for too long. I now have a new battery. The charge controller allows the battery to be charged to 13.7V (well that's what it says, my volt meter says 13.4V) and then keeps it at that voltage (at least during the day, drops lower at night). Is this voltage too high for my battery to be kept at and would this cause my battery levels to drop more quickly? Ps.. dont suppose anyone recognises this charge controller and can tell me what the 3 buttons do? I bought the kit from Bimble solar, nice chaps and helpful so they may reply but thought I'd ask here as well.