I'm building a solar panel (12 volts, 3 watts,250 mA)+ batterypowered weather station type of thing + autonomousgardeningwith arduino and sensorsat the heart of it. I need 12 volts for a couple of the components in this project as well as 5 volts for others, so I figured I'd throw 18650's in3s1p or 3s2p to get 12 volts and run asmall buck converter off that to get5 volts. Most of the components, including the 18650's,will be housed inside a 16" cube box and will sit in direct sunlight most of theday. The box willbe painted white and the top half of it will be allsoffit vents (16" wide on each side) to help keep the heat down inside.Is this enough to keep the 18650 from overheating or is there something else I could do for prevention?
P.S. - I also thought about lining the inside walls and roof of the box with reflective foil insulation (used as insulation in roofs, walls, garage doors in homesand RVs to help keep them cooler in the summer), but wasn't sure if that's a good idea with all the electronics inside. Maybe make a double wall and put the insulation between the walls??
P.P.S. - Also, I thought about installinga Noctua 120mm fan (12 volts, 50 mA)and an outdoordryer ventin the boxto act as an exhaust system so the fan kicks offwhen the box reaches a certain temperature, but worry it'll draw too much current from the panel, charge controller orbattery and hamper the circuit. Maybe add a second solar panel in parallel to help with the extra load and only run the fan during sunlight hours??
P.S. - I also thought about lining the inside walls and roof of the box with reflective foil insulation (used as insulation in roofs, walls, garage doors in homesand RVs to help keep them cooler in the summer), but wasn't sure if that's a good idea with all the electronics inside. Maybe make a double wall and put the insulation between the walls??
P.P.S. - Also, I thought about installinga Noctua 120mm fan (12 volts, 50 mA)and an outdoordryer ventin the boxto act as an exhaust system so the fan kicks offwhen the box reaches a certain temperature, but worry it'll draw too much current from the panel, charge controller orbattery and hamper the circuit. Maybe add a second solar panel in parallel to help with the extra load and only run the fan during sunlight hours??