Hi all

I need to make a lighting ring using a COB LED. The lighting must be bright and also last for a 5 hour period. What would you recommend as I can only use a 9V battery due to limited size of housing.

I have limited space of 48mm for the ring, and need a 20mm center clearance for a camera lens.

Thanks in advance

 

Then first select the leds that you want, noting their current drain, then select a battery with a Ampere hour rating that will give you that, you may find you will go for lithium-ion or nickel.

So example leds take 300mA, for 5hours, that's a 1500mAh battery minimum.

 

Then first select the leds that you want, noting their current drain, then select a battery with a Ampere hour rating that will give you that, you may find you will go for lithium-ion or nickel.

So example leds take 300mA, for 5hours, that's a 1500mAh battery minimum.

Many thanks can you get a lithium battery as small as a 9 Volt?

 

Do you mean Physical Size, like a PP3?

At best a PP3 will be 850mAh, you're better going for the 18650 cells or lifepo battery.