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So, the fun part will start now. Building the thing!
I'm not sure if the type of solar cells usually supplied with these type of devices are the best for your purposes, but of course, the best way to discover, is trying.
Just a hint: unless you are planning to put something over the solar panel of these garden lights, don't buy just one, because in less than a year the shiny surface of the solar panel will become almost opaque, and it will supply half the current.
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31-08-2017, 15:46
Alan,
I looked at your links and that's almost exactly what I tested few days ago that I bought from aliexpress. The problem with that is to mount it. You are right we see strange data ... Just below the picture we see ni-mh solar cell ????? We may think it's the battery certainly better than other models using ni-cad. Protection level is IP65 which is excellent, and that's what I'm looking for. Other models didn't indicate IP level. Lower in the page we see more specs : crystalline silicon 2v / .08 watt. This makes sense. All othes similar lamps I've seen were 0.06w and much less expensive than this one.
So I'll try ... J Guy
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Hi.
It shouldn't be difficult to achieve IP65; just encapsulate the whole circuit in a "potting compound" or a surface treatment . The batteries are often a soldered, wire-ended cell, so the only exposed component need be the switch. That could be a magnetic reed switch, but probably not at a reasonable price point. However, encapsulation is no use if you want to "recycle" any of the components, or the enclosure. Interestingly the "10 packs" of lamps on the same site, look very similar but are specified as Amorphous silicon panels and with a much lower IP rating.
The "crystalline" PV panels appear to be about 10 cm2, but that should deliver around 150 mW. However, the crystaline PVs in the garden lights that I've seen have used just "slivers" (offcuts?) with a much smaller overall active area. Also, don't expect too much from the batteries, they are often just "button" cells (which is generally sufficient for one day).
However, I did find two with a "real" AAA and AA NiMH cell in a "battery holder", so I could easily measure them in my charger/tester. The AAA was marked 300 mAh (only about 1/3 of what's possible in that physical size) but actually measured 36 mA (yes ~12%), the AA was marked 600 mAh (about 1/4 of what's possible) and actually measured ~50 mAh (yes < 10%). Some Chinese specifications are no more than "think of a number".
Cheers, Alan.
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You may be right that led lamp is not worth the price but I do not intend to use it. I will remove everything but the solar panel. You may also be right that it's not a real IP65 ... I'see in a few weeks. For the batteries, I previously tested these chinese batteries. I found exactly the same thing. I asked for a refund and got it. I will never buy any batteries from china.
J guy
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I will test with one of the dome of my cameras before ordering. thanks.
