Intro: Solar Supercapacitor Charger and LED Jar
I made this just before the overnight camping trip to coast, in bit of a rush, because of time limit and was so hot and with solder iron on even worse and sugru was nearly melting in hands, so my tip try not to do it on hot day and dont leave it till last minute;)
The way it works is very simple:
Supercapacitor gets charged with solar, by connecting two parts together and placing this in sun (see picture)
When charged capacitor is connected to LED lamp the light is produced ( does fade with time, more farads more time it stays lit)
4.8V 50mA PowerFilm solar cell (you can use any make, the one with larger current would charge capacitor quicker)
3V Supercapacitor 20F or more
2.9-3V LED module
2 X 2.1mm X 5.5mm DC socket female and 1 male connector
Fin clear film sheet
Small glass jar with screw on lid
Moulds (shot glass)
Step 1: Solar Panel
Take small piece of protective film of the metal strips at the sides, use your DC meter to determine the positive and negative side (cathode, anode) Solder diode to + and some wire to -, then solder other end of diode to + on dc socket and negative to -, I find it easier to stick the wire through the hole then solder.
The reason for using diode is to make sure that electricity flows in one direction.
For finishing, cut solar cell shape out of clear film, cut hole for dc socket, fit the panel in and apply sugru on sides, this step is quite tricky. The reason for using film is to give it more protection as these modules are not waterproofed and not UV balanced.
Step 2: LED Jar Light
Connect led module to female dc socket by soldering, same as usual + to +, - to -. I used piece of diode wire it is nice and sturdy and only need short one, so its perfect.
Take the lid of a jar and make hole in the middle, stick the socket through and screw on the nut and washer (comes with socket).
You can go one step further and make it more safe and pretty by making colourful lid and rubber sleeve. To make sleeve wrap double layer of cling film around jar, and then form sugru around it, when set remove, if it not coming off, gently run the knife in between the jar and set sugru to loosen. This not only protects the jar from braking while travelling, but also works well as a stand for capsule shaped capacitor enclosure. For the lid, you can make permanent one by sticking sugru on it or removable, like me, using clingfilm, this option give you another option, whether to to use this as lid or as part of lamp when its lit, my option again is second, so for this you would need to make hole for connector by cutting it out with knife (can do this when set)
Step 3: Supercapacitor
For this I used solderless connector, so if you have the same one, just trim the wires a bit, bend top so it grips better, insert the positive wire (longer one) to + of connector and negative (arrow pointing down) to minus, I used round piece of black foam and place it in between the capacitor and connector, by poking holes in foam then sticking wires through, this makes it more sturdy and other benefits (sorry forgot to take picture of this)