Solar :garden light

[leoneil]

Hi, guys i am building a solar garden light, with LED of around 1 or 2 watt,
wat kind of rechargeable batteries can i use , if i want a backup of around 8-10 hrs..

thanks in advance.

 

[kpatz]

What's the voltage and current rating of the LED you're using?

The voltage will determine how many cells you need, and the current times the backup time will determine the Ah/mAh rating of the battery.

So, for example, if you are using a 4 volt LED that draws 300 mA, using 1.2V NiMH cells you would need 3.33 cells (make it 4) and to get 10 hours you'd need a 3000 mAh capacity. (C sized cells).

Seems like a lot for a solar garden light... most solar garden accent lights are a fraction of the wattage, usually 1-2 miniature white LEDs that draw 1/10th the power. The solar panel is going to have to be several inches square to produce enough power to charge the batteries.

 

[Hero999]

How big do you want it to be?

As mentioned above, a solar panel capable of recharging the batteries it going to be quite large.