batteries

[labador]

Question,

I Have a Nichia NSPW500GS-K1 5mm in a pocket light used for a project and running it on 2 / 3volt coin size batteries, If I switch to 1 double AA battery for the light is it only still 3 volts with the AA. Is 2 /3volt coin size batteries more power then 1 AA battery.

Next question I want to switch to a 10mm white light led for more lighting power can I get away with using a double aa battery for that and will it keep it bright for 4 hrs or more being on that long. Is a 10mm white led more powerful than a 5mm white led and will I get more light and a brighter light with a 10mm led.

Thank You

Jim

 

[DM51]

Welcome to CPF, labrador.

We have a sub-forum for discussions relating to batteries, so I'll move your thread there.

 

[UnknownVT]

Nichia NSPW500GS-K1 5mm in a pocket light used for a project and running it on 2 / 3volt coin size batteries, If I switch to 1 double AA battery for the light is it only still 3 volts with the AA. Is 2 /3volt coin size batteries more power then 1 AA battery.

I think what you said was the light right now is using 2x 3V coin cells?

If that is the case then you have 3V+3V = 6 Volts at the LED.

A single AA battery is rated at 1.5V which is (obviously) only 1/4 that voltage.

LEDs are basically Diodes - most 5mm white LEDs have a forward voltage (Vf) of more than 3.0V, below which the LED will not turn On (ie: light up)

Your Nichia NSPW500GS-K1 Vf = 3.2 typical and 3.5V max
(ie: do NOT exceed 3.5V - your light is getting away with 2x 3V coin cells because they just cannot deliver enough current to damage the LED)

So I would say to use AA batteries - try only 2 in series and see if that works.
But I think more likely one needs 3 in series = 4.5V,
but because AA batteries can deliver much more current than coin cells there has to be a limiting resistor to drop the voltage to below the max rated Vf at the LED - otherwise the batteries will blow out the LED.