Instructables

Solar Lamp Hack to run off wall power!

Featured
Picture of Solar Lamp Hack to run off wall power!
IMG_0952.JPG
IMG_0948.JPG
This Ikea Solar Lamp, that I bought at Ikea, has a solar pack that charges batteries to power the 16 LEDs inside. This is very bright, but what if the batteries died and there is no sun because it is cloudy outside or for some other reason? Well now you can plug it in and it will run off the main supply! This is the first Ikea Solar Lamp hack to run off wall power.
IF YOU RUIN THE LAMP, IT IS NOT MY FAULT. THIS IS AN EDUCATIONAL HOW-TO PROJECT FOR THE SAKE OF THE LAMP.


 
Remove these adsRemove these ads by Signing Up

Step 3:

Mark the negative side with a marker so you don't mess the polarity up. 

Solder the 22 ohm resistor to the positive side of the connector. Then the adapters positive wire to the 22 ohm resistor.

Solder the negative side of the adapter to the negative side of the connector plate.

Jam it all in the plastic case thing. MAKE SURE you don't have anything touching that should not be touching.
Put the connector plate together to the dark base. Don't completely put it together yet.

Step 4:

Picture of
I drilled a quick little hole for the wire. 
Public Service Announcement: The IKEA solar lamps aren't all the same. Some of them have an array of 16 small LEDs and some have 3 big ones. The ones with the 3 big LEDs are brighter. So look underneath at the actual light source and choose accordingly.
aterz2 years ago
Thanks, very interesting!
Is it possibile to have a simple schematic of the circuit? As far as I understand the charger is directly linked with the leds using the 22ohm resistor to keep the current low and the battery has the diode in series with the + pole in order to avoid the current of the charger to enter the battery. Is it correct? At the end the diode reduces by 0,7volts the Voltage to the leds thus reducing the luminosity, is that right? Thanks for the answer.
It would be interesting also to open the solar panel and the battery in order to have also the battery recharged when the charger is plugged in...
alpe_97 (author)  aterz2 years ago
Hello! Yes that is correct. (I had to read it a couple of times though... haha)
It might be hard to draw a schematic of the insides of the battery pack because there is ICs in there.

Find the positive wire coming from the little circuit board that connects to the connector plate (that is what connects the lamp's LED and switch.)

Now just un-solder the positive wire, coming from the little circuit board, FROM the connector plate, which goes to the lamps switch and LED array, and insert a diode with the stripe closest to the connector plate(so the stripe is also farthest from the circuit board.


Then on the connector plate on the Lamp. Find the positive and solder on the resistor then the wall adapter to the resistor.

If you need more help, just ask! ;)
aterz alpe_972 years ago
Hi,
I did it. I saw that leds adsorb any current you push into with maximum 2vols fall. I eden tried to connect 12v power and I saw corrent up to 0.8amp! They were fine.
So ok diod, resistence at 40ohm, power supply 5volts, current around 50-70mA so only 0.25watts consumption half of which falls on the resistence that so has it is enough a 1/4watt normal resistence.
Next step is to put a potenziometer... From 10 to' 100 ohms
Ciao
Andrea
etanol2 years ago
Nice! I actually do something very similar but with an old phone charger and Ikea solar lamp, but without resistor and diode.

Use it when the battery is low and just leave the solar battery pack in so it powers the lamp and charges the batteries at the same time. The charger does not seem to mind, it does not get too hot either. As the batteries could get damaged when overcharged it is not wise to charge them for too long though.
pacwoods2 years ago
Why not just replace the rechargeable batteries?
Did something very similar for my Dad's solar garden light array.

We actually removed the solar panel and charger (as it failed after around 5 years of continuous use).

We used a old phone charger and ran it direct to the LED lamps. There was enough electronics in the lamps to regulate the current (as the lamps gradually change in colour).

Great use of old phone chargers - which we all have cupboards full of!
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!