This Desktop Energy Seed Lamp is interesting. It uses old batteries as a power source. All of the batteries are put in parallel using two large metal plates and a jewel thief circuit (I prefer the rusty nail implementation though) is used to create the larger voltage needed to power the LED circuit. As long as the batteries all have about the same amount of charge left the circuit should efficiently drain the remaining energy out of the batteries. I am not a big fan of Parallel LED circuits, but they may last long enough not to make that a concern. Have a look at the full article, it documents the mechanical and electrical process of this design very well.
"Today I will show you something very interesting. It is not a killing robot or skynet (not yet). It is a desktop ambiant light that use dead alkaline battery to power itself. This design can hold up to 15 batteries. It use a single joules thief circuit to power 50 LED!"
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I am amazed at the number of LED’s that you can run off of a single AA battery with this circuit! I may have to make one tonight, as I just received a brand new batch of 100 White LED’s from an overstock website.
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this design makes people feel better about using alkaline batteries – it should not – thats sending the wrong signal, use rechargeable batteries in the first place
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@ arni: Are you a magic mind reader all of a sudden that you somehow know what everyone is feeling re: alkaline batteries? The reality is that they exist and are used, and even those of us who regularly use rechargables somehow end up with some dead ones here and there. This is a truly creative and clever design, and definitely does not warrant such lazy and regurgitated criticism.
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Such a fantastic design, and a great information about alkaline batteries.
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Interesting article. Were did you got all the information from… 🙂