The average consumer will not take care of his solar lights the way you do!
By removing the rechargeable batteries, cleaning the contacts and stocking your solar lights inside during winter time you are considerably extending their life-span.
Regarding the rechargeable batteries, according to my experience 2 years before replacement is very good.

I’m not sure where you can find exactly the same solar driveway lights but you can check some other models at http://www.clean-energies.org/Solar-Path-Lights_c_39.html

Maybe The solar garden light is located in the shade. In this case he photocell triggers the light during the day and the battery is too low at night.
Try to install your solar light in a sunny location and see what happens.

Thanks for sharing. I’m publishing your post so people who are interested in your hybrid solar system can contact you directly.

We believe that our hybrid CPV/T system could be successfully used in your mix of commercial and industrial applications and marketed as a very efficient use of solar energy in a number of states and countries. The benefits of such “marriage” are numerous, including taking full advantage of the present day energy credits and subsidies.

Anco Blazev, Ch.E.
President & CTO
SolarTech of AZ
480-381-7502

For this kind of application we always recommend a very bright solar light. You can go without hesitation for the 108 LEDs solar flood light at http://www.clean-energies.org/Solar-Flood-Light-108-LEDs_p_14.html this solar light is designed to illuminate large areas, signs, statues, etc.

Hope this helps

Thanks for your help!