This is a very simple mod that will add a super capacitor into your wireless keyboard (i chose to leave the battery compartment in so i can use batteries if i want), there is a few things to consider before you do this mod, firstley if you keyboard is very power hungry this may not be for you (but don't let that put you off, it can never hurt trying just hooking one to the battery contacts for awhile) and if you use your keyboard allot it may have the same effect as if it was very power hungry.
A note on safety:
Remember these capacitors hold allot of charge, because of the low voltage you are unlikely to get a shock of it unless you lick it (I know it's tempting, but try to avoid it) but nevertheless, be careful and always discharge the capacitor before working on it.
Also it should be noted that super capacitors don't like being charged at more than the rated voltage, this is why we charge it with a voltage regulator.
Step 1: Gather Materials
-Super Capacitor (I used a 10F one) (I got it here )
-Some sort of socket (I used a phono one)
-A plug to fit your socket
-Wire (I used some scavenged from some cat5e cable)
-A 2.5v regulator (TS1084CZ-2.5) (I got it here )
-2x Small Capacitors (Optional) (I used 2 10uF ones)
-A small piece of stripboard / protoboard / PCB
Step 2: Crack Open That Keyboard
Step 3: Decide Where to Put the Super Capacitor
Step 4: Install Your Super Capacitor
Start by dremeling off any unnecessary plastic around where your super capacitor is going to go, then solder a different color wire to each lead of the capacitor, insulate with tape or heatshrink if needed ( i used a pice of plastic in the keyboard to separate the leads so this wasn't nessery). Now hot glue the super capacitor into place and root the cable coming off it to the keyboards PCB (or to the battery holder) and solder the negative cable to the appropriate point on the board.
Step 5: Add Charge Socket and Super Capacitor Isolator Switch
Now how you install the switch depends on what one you have, if you have one which the toggle can go through the plastic of the keyboard and still be moveable grate, mount it on the underside of the hole (inside the case). If you have a small switch (like me) solder 2 lengths of wire to it, now carefully thread the wires through the hole, turn the keyboard over and inject liberal amounts of hot glue into the hole
Step 6: Connect It All Up
Step 7: Put It Back Together
Step 8: The Charger
Step 9: Your Done!
Now you never need to wait hours for batteries to charge.
Enjoy your fast charging Super Capacitor keyboard :-).