Solar light problem

Hi Guys,

I have a bit of a problem.

I have tried recreating these solar garden light designs:

Solar Light circuit 1

Interesting Electronic Schematics and Circuits - Novotill circuit 1

using exactly the components they specify, a 1.2volt ni-cd battery and this solar panel:

Solar Cells sixth one (2v @ 45mA)

Unfortunately I have two problems:

1) I can’t get the circuit to switch off the LED as it always remains on. Which is because the solar panel does not produce enough voltage at low light levels to switch the first stage transistor on, turning the whole circuit off.

2) Also the battery does not charge! I leave the circuit in direct sunlight for 30min and then in a dark area and it lasts for less than a second. But when I attached a 4.5v panel the circuit works well.

I understand it’s the solar panel which is causing the troubles, but it is a 2v panel and that’s what the specs use. I have tried using IN5817 diodes with low Vf for better charging but still doesn’t work.

Is there anything that can be done with keeping the exact same solar panel??

Thanks.

Where are you in the world?
If you are in upper North America then guess what? It is winter and the sun is weak because it is low in the sky. Today was sunny and tonight my solar garden lights were normal for about half an hour after charging all day. In summer they light all night long. I am in Canada but very close to the USA border.

A window's glass reduces the sun's intensity to half or less. The solar panel must point directly at the sun, not straight up and not to one side.

Im in australia and its very hot at the moment. I have been testing the circuit in direct summer sun...

Buy a solar garden light for only $2.30.
I bought two but one didn't work so I took it back to the store. They threw it in the garbage and gave me another one.

I need the circuit to be as small as possible so i am trying to build it using smd components and with a small solar panel.