No light at 2.7 volts

[Albinoni]

I've got a LED torch which takes 1xCR123A battery and I today when I turned her on in the afternoon sometime she decided to not come on anymore, so I thought oh no hope its not the torch, anyhow I decided to try a new CR123A battery and she worked like a charm.

Now time to test the old battery on a multimeter (Hioki Pencil HiTester 3246) and I got a reading of 2.3 volts. Now I was quite surprised at even this voltage the LED refused to come one, had the voltage been under say 1.1 volts than that I would of understand but 2.3 I would of thought there would still be some light.

 

[Helmut.G]

the battery has normally got ~3,5 V, it's completely drained and cannot deliver any energy to the LED
The LED voltage is only important if there's no circuit in your flashlight, in this case the battery voltage would never drop below 3 V, the all white LEDs stop working at this point

 

[B@rt]

Albioni, I asked you before to stop asking questions that can be found with very little effort. CPF has a wealth of knowledge, but some own initiative in finding the answer is expected.

Please take a week off to familiarize yourself with the concept.