Shop OBEX P1 Docs P2 Docs Learn Events
Solar Light Help — Parallax Forums

Solar Light Help

NWCCTVNWCCTV Posts: 3,629
edited 2010-07-15 01:07 in General Discussion
Does anyone know what type of solar panels are being used to manufacture the garden style solar lights? I have searched EBay for solar cells, but all I can find are 3"x6" that put out a whopping .5V. I am going to purchase a $3.00 one just to open it up and see the insode, but that does not tell me what type of solare cell is used. Thanks for the help.

Comments

  • stamptrolstamptrol Posts: 1,731
    edited 2010-07-13 12:48
    The ones I have use a small array about 3" square feeding a 1.2 volt nicad cell. You can rest assured these are not top of the line solar cells, but they do work for the intended purpose. Watch the Home Depot or Wal Mart in your area; they will be on sale soon. You'll get the cells, batteries, control circuit and the LED for not much more than the 0.5 volt cell you're considering.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Tom Sisk

    http://www.siskconsult.com
    ·
  • BradCBradC Posts: 2,601
    edited 2010-07-13 13:17
    Mine have small strips of solar cell wired in series and potted to provide the 1.7v required to charge the batteries.

    I thought they were quite resilient until the dog found them..

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "I mean, if I went around sayin' I was an emperor just because some moistened bint had lobbed a scimitar at me they'd put me away!"
  • NWCCTVNWCCTV Posts: 3,629
    edited 2010-07-13 18:49
    OK, I understand what you guys are saying, but what I am asking is what are they using as far as solar cells to get that much power from the smaller sized cells.
  • FranklinFranklin Posts: 4,747
    edited 2010-07-13 22:38
    There is probably a boost converter in there or at least series cells to get to 1.7 volts. Take one apart and see how it works and what it is actually putting out. The cells are probably cheap chinese cells to cut cost.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    - Stephen
  • Spiral_72Spiral_72 Posts: 791
    edited 2010-07-14 18:24
    I was under the impression that a "Solar cell" is made up of individual cells wired in series and parallel arrangements and packaged on a single board or panel. Jameco has a bunch. For and given size..... 2x3" for example you can have (again for example) 0.5V at 250ma, or 1V at 125ma or 1.5V at 80ma off the same footprint.

    Am I right??

    I was also looking at Pitsco.... while grossly overpriced, they have different 2x3 cells in a nice little sealed plastic enclosure. They're all the same size with the same enclosure but the rated current is inversely proportional to the voltage.


    So they are using series cells (either wired or manufactured in one unit that way) to make about 1.5V at maybe 50ma or so to trickle charge a battery for 12hrs during the day.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "puff"...... Smile, there went another one.

    Post Edited (Spiral_72) : 7/14/2010 6:30:34 PM GMT
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-07-14 18:34
    I think you're right about the boost converter. I've had several of mine apart to repair bad solder connections or to bridge defective switches and have seen a chip-on-board device that handles the light detection/charging/LED driving. The solar cells themselves seem pretty rugged, however. I've had deer kick them out of the ground with no apparent damage.

    -Phil
  • NWCCTVNWCCTV Posts: 3,629
    edited 2010-07-14 18:58
    So in series you can stack them on top of each other????? Seems to me that they would be obstructed from light and would be difficult to charge. Any ideas on a boost converter to use? I would like to make some of my own lights in pieces of driftwood, etc. to place in my yard. I have tons of LED's and diodes but want to put at least 2 or 3 LED's in each unit. Would standard transistors maybe work for boosting the power? I have used them to build a set of 8 LED's that will all run on a single 9V battery.
  • FranklinFranklin Posts: 4,747
    edited 2010-07-14 23:10
    www.google.com/search?q=boost+converter+circuit&rls=com.microsoft:en-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1&rlz=
    Start reading here.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    - Stephen
  • NWCCTVNWCCTV Posts: 3,629
    edited 2010-07-15 01:07
    I bought one of these solar chargers some time ago on EBay: http://cgi.ebay.com/USB-Solar-Battery-Panel-Charger-Cell-Phone-MP3-MP4-/130395874736?cmd=ViewItem&pt=PDA_Accessories&hash=item1e5c3325b0

    I tore it apart and find that the solar panel is 4" x 1.5" but is a bit thicker than standard solar cells. Funny thing is that the cell itself with nothing else connected is putting out 6.88V, at a measley .1 Amp. Seems to me that it would take some time to charge a cell phone with that low of amps coming out of it.
Sign In or Register to comment.