I was just looking at the Coast HX5 Torch and the different run times with the 2 batteries
http://www.torchdirect.co.uk/coast-lightweight-led-torches/coast-hx5-focusing-led-torch.html
How come the run time with the NiMH is so much less than the alkaline, I get that ones 1.2v vs 1.5v which is reflected in the lower lumens but if you were to use a 2500 eneloop pro it’s going to be similar capacity to the alkaline so should give similar run time or have I missed something???
In the tests, one can see that alkalines droop quickly in voltage under continuous load. At low current the alkalines have more voltage for a short time, but in continuous use the voltage falls way below that of NiMH. So the current with alkalines falls off too and they last longer but produce less light. Regulated boost and buck drivers try to reverse that by drawing more current at lower voltages, but that only works within limits.
The description says:
“Using 1 x AA alkaline battery:
130 lumens; 3 hours, 45 minutes run-time; 79 m beam range”
What it doesn’t say is that the 130 lumens and 79 m only apply to the first few minutes, or maybe seconds, of the 3:45 run time.
LED Lenser, which is really the same product line, counts run time down to 1 lumen output.
It is too bad they can’t sell things for their truly advanced optics and good build quality without making misleading claims.
Maybe they got it wrong? Or because of the lower voltage they have a harder time of stepping the voltage up to 3v from 1.2v which is the nominal voltage of a NiMH usually my NiMH are resting on about 1.37 volts fresh of the charger they are around 1.5v but either way NiMH should give a longer run time.
TOTALLY agree with this, I want one perfect torch that ticks all the boxes and I don’t mind spending a reasonable amout once if I find it so bought their P5R.2 which shows 4 hrs run time. Switch it on … absolutely amasing for such a small torch and a quoted run time of 4 hrs … granted down to 1 lumen …… BUT
Run it for 5 mins and the output drops massively (to the extent a 140 lumen torch is considerably brighter when you switch it on) turn it off and immediately back on again and it’s immediately incredibly bright again …. I’m guessing it’s designed to work like this to extend the run times albeit at a much lower output.
The reality though, it starts to flicker when the battery is getting low which I doubt was any more than 1 hour …… nowhere near 4 hrs …… real shame, even if it had of kept a decent level of brightness for 2 hrs I would have hung onto it but instead it’s in the post as I type heading back to the seller for a refund.
Cheers to both of you for the info an the alkaline vs NiMh !!