Easy Garden Solar Lights Project

[colerainescotty]

Hi guys,

I am one of those people who have bought the cheap solar stake lights (crap) from local shops just to add a little bit of interest into the garden at night. I seem to buy them every year even though I know they are really crap, especially for my Northern Ireland weather (loads of clouds) so...

I was looking for a possible project...My thinking is to adapt the current stake lights and perhaps add a 1w led and larger solar panel on the top. Not totally sure how it would work out but this is my line of thinking at the moment. They do not have to light up paths or anything as there are mains powered security lights for that. It is simply to add a bit of low light to the garden borders at night (and to give me another project ofcourse lol)

Have any of you done anything like this? Or would you recommend a cheep and cheerful way to adapt the cheap lights into something more meaningful?

I had thought of getting a 12/24V garden light setup but I am not sure I wanted to go to too much trouble just yet. I think if there is a possibility I may be able to use my existing casings etc and add 1w leds and better battery etc it might look quite tempting to try.

All thoughts are very welcome and would love to see some of yours if you have made any yourself?

I have attached the current led lights I have that I would love to adapt / upgrade
solar-garden-lights.jpg

[tater1337]

when they die, try banging them a bit. it seems the batteries are held in normal spring contact holders and a little corrosion tends to do a lot. remember that you got them cheap, so you need to look into whether it woudl be more cost effective to get a new light or screw around with a faulty one.

I do admit they do look pretty in the yard, i have about 50 of them, some are over 5 years old

[colerainescotty]

Thanks for the reply I know what you mean but I was even thinking of buying brand new ones and upgrading the solar panel, led, battery or internals to make it more effective. Has anyone else done this and had good results?

I was thinking perhaps a brighter led, bigger mah battery and larger solar cell or cells on top? I would love them to work all night in the winter

[Sunking]

All the Solar Garden lights use a 1.2 volt 600 to 800 mah NiCd battery. If you do the math is just under 1 Watt Hour of capacity. Now do a little more math' how long do you think a 1 watt LED is going to last with a 1 watt hour capacity battery?

Your answer had better be less than 1 hour.

See the problem? Adding a larger panel and LED is not going to buy you anything. Your battery is the choke point.

[colerainescotty]

I see what you mean sunking, certainly the existing battery could not stay. I did think about upgrading the battery too, to a much higher capacity or even going for 0.5w led etc to help use less current. What would you recommend for a nice little setup but again something not crazy money? Basically the little solar lights are good if they would last longer into the night or even be just slightly brighter and last longer. I only need around 5 for a shrub bed just to give comfort night lighting or add a little interest.

Thanks again

[SunEagle]

I see what you mean sunking, certainly the existing battery could not stay. I did think about upgrading the battery too, to a much higher capacity or even going for 0.5w led etc to help use less current. What would you recommend for a nice little setup but again something not crazy money? Basically the little solar lights are good if they would last longer into the night or even be just slightly brighter and last longer. I only need around 5 for a shrub bed just to give comfort night lighting or add a little interest.

Thanks again

The biggest problem I have seen (and experienced) with similar products is that sometimes those lights get blocked by shade due to the trees and plants surrounding them. Then they do not get fully charged back up.

The second short cumming is the type of film that is used to protect the solar cell. The plastic used gets foggy and opaque after a year or so in direct sunlight and then no longer generates enough to recharge the battery.

Lastly as Sunking stated the batteries are usually on the very low end of quality (it keeps the price down) so may not last daily cycling.

My suggestion is to look for small batteries that are used in those 808 keychain cameras. They are rated 3.7volt between 250mah and 400mah and can provide a high number of cycles but cost less than $10 bucks ea..

[tater1337]

The biggest problem I have seen (and experienced) with similar products is that sometimes those lights get blocked by shade due to the trees and plants surrounding them. Then they do not get fully charged back up.

I'd argue that, I have the cheapest dollar store solar lights and they repeatedly get buried in tall grass yet still work

The second short cumming is the type of film that is used to protect the solar cell. The plastic used gets foggy and opaque after a year or so in direct sunlight and then no longer generates enough to recharge the battery.

depends on the lights, mine are so cheap they just have the cell bonded to glass.

Lastly as Sunking stated the batteries are usually on the very low end of quality (it keeps the price down) so may not last daily cycling.

My suggestion is to look for small batteries that are used in those 808 keychain cameras. They are rated 3.7volt between 250mah and 400mah and can provide a high number of cycles but cost less than $10 bucks ea..

the problems i've seen with my dollar store solar powered LED lights.....
they have near non-existent solder joints to the solar cells, repairing or even swapping out once cell for another is near impossible.
they use spring type battery holders of a minimalist design, causing any tiniest corrosion causes the batteries to not charge
they seem to design them to have charge and discharge rates at unity, I mean they seem to think that if they get one hour of sunlight, they'll give out one hour of light. good for summer, bad for winter.

I just checked them over and realized some of them are over 4 years old. I am not sure what the failure rate is for mine, but much less than 50%....even if it was, a yearly cost of $0.50 per life was worthwhile, without upgrading