Make a Solar DS "light" (Version 1)

Step 15 Enjoy not Using the Charger!

Turn the DS on. If it works, good job! If it doesn't, I have no idea what you did wrong (or the battery is dead).

Ever since I did this to my DS, I have never had to plug it in to charge it. If you have used for a while, set it in the sun to charge some. ~~Don't let it sit in the sun all day every day, it's probably bad for the battery. The cells don't produce much current, but it's probably best not to risk the battery.~~ (see update)

Enjoy your DS "light"! :-)


Ratings and comments are appreciated. If you have a question, don't hesitate to ask! I'll gladly answer it!

Comments

[d3z0rian]

it is possible to use this?
http://www.batteryjunction.com/prcimopfor3l.html
Enlarge the image and the specification says "Overcharge Protection voltage 4.275 +- 0.045V"

[dark sponge]

Awesome idea!!! I'm going to have to order one of those! Is it ok if I add it to the Instructable if I credit you?

[dark sponge]

Yay! I just ordered three of them!

[d3z0rian]

Great hack for the DS, good luck!

[dark sponge]

Thanks!

[appsman]

This circuit has a risk of over charging and damaging you battery. Even though the solar cells don't output too much current, if they feed the battery when it is nearly full, they will damage it. The Li+ cell in the DS gets charged to no more than 4.2V but this circuit will keep charging beyond that. One thing that might save you is that it CAN'T charge for more than 8 or 10 hours at a time. So if you use it frequently you might stay ahead of over charge. But if you leave it by a window for a few weeks and never use it, that might be bad. I predict you're battery will not last as long as normally charged one, especially if you charge with the adapter and then top off with this. One thing I'm not sure about is the fire risk from this kind of over charge. It really is a LOT safer to go in through the adapter input. Or as another poster suggested, use a linear regulator to keep the voltage from exceeding 4.2V. There are some that eat only 10uA which is nothing compared to your 30mA.

[dark sponge]

I never charge it for very long, and I only charge it after playing it for a while to help prevent overcharging. It's ok if the the voltage exceeds 4.2v, because they are charged at a higher voltage. You might have gotten that confused with the voltage of a fully charged battery, 4.2v. I like your idea of the linear regulator though. I might try that.

[soccerray]

I think it's 5.2V

Is this a correct diagram? I am just learning about circuitry in school and am very interested by this project. I drew this up after checking my DS for its power information.

http://i41.tinypic.com/2crw0o7.png

[dark sponge]

5.2v is the power that is supposed to go through the charging port on the DS.

[buZztiaan]

sweet stuff :D wonder how you could improve it to not overcharge ...

[InfamousKirch]

wire the panel to a 5v regulator & plug it into the charging port, or hardwire it to the innards of the charging port.

[buZztiaan]

yeah, would fix it all, and use the LED to indicate charging is done :)

[dark sponge]

I already considered that. If I used a 5v regulator, I would have to wire all of the cells in series to get a high enough voltage for it. With the panels in series, it only produces a maximum of 30 ma. Put that through a 5v regulator, and you ends up even less. I would be left with so little current it could probably barely power the charging LED, ending up with next to nothing for the battery.