Review: Ultrafire WF-504B with 5-mode R2 drop-in

79% output now. This is a grey 2400mAh Trustfire cell.

78%. Not dropping appreciably. Got the 18650s all charged again.

Wow now that is pretty good.......

76% and going strong. There sure are going to be a lot of data points on the runtime graph.

76%

Down to 74% now. Wonder if it'll still be lit in 9 hours time when I get up in the morning?

72%. Off to bed so I'll stop boring you with updates till the morning when a runtime graph will appear. Assuming it has decided to turn off by then. I reckon another 3-5 hours should see it.

Long enough Mr. Admin? Or do I need to get some higher capacity cells?

Dude with higher capacity cells that light should last a year with low running...lol.

This has been a real white-knuckle thriller for me, percentages trickling in all day long, I love it!

24 hours or I'll eat my hat.

58% and still going. Better look out the hat seasonings!

We're now below 50% but it is still emitting light. I'll let it run till the cell protection cuts in. Now 47%

Still lit. Down to 29% Now 15,555 data points.

Looks like it'll still be lit when I go to work. It is just possible that hat eating won't be necessary.

Now down to 6%. Don't think I'm getting a whole day out of it.

How are you going to cook your hat?

Steamed....lol......with a little bbq sauce for good tasting. Thanks for doing the runtime....the light is still doing a good job at lighting up, have you tried turning the light off to see if it will come back on.

Came home to see to the hound - it is still lit. Now down to 2% after 28hr 20 minutes. It is about as bright as a sick glow-worm but it is still shining. Now 20,385 data points. This is impressive, I'd have thought the cell protection would have cut in by now.

That's a very impressive light then. And it sounds like most of the time the light was actually strong enough to be usable. But are you sure it has cell protection?

I'll save my dinner for another day....

The dropin won't have protection, but the cell does (or at least ought to have). Will see when I get home again in about 3.5 hours. There will be a lot of data in the graph. I have seen the protection circuit work in several of these Trustfire cells - couldn't say for certain about this one. If the voltage at the end is less than 2.5V I won't even try to recharge it. The protection circuit is supposed to cut in at 2.75V.

Once I get home, I'll try switching it off and leaving it for a bit before I try to turn it on again. Of course, it could be like some that will run, but not start when the voltage gets too low.

Ah, the CELL has protection? I didn't know that. My Akoray K-106 has an option cell protection feature in which it will not run when the current is too low, that's why I thought that it was up to the flashlight to protect the batteries.

The beauty of these lights is that the battery "rejuvenates" itself when it sits. (Maybe our in-house chemist could explain this Don?) So assuming that you were lost in the wilderness with only one battery, you could theoretically use the light all night long, then turn it off during the day, and it will turn on again the next day again at almost full brightness.

Well protection can go both ways.....the circuit on the cell will cut-off or the light will have one built in causing the light to turn off or give you a warning like blinking and such. If the light has built in low voltage protection then thats when i like to use unprotected cells.....nice to see that the the light is still going.

31.5 hours now. 1%. Dim enough that I can now look into the LED. Time to check the cell voltage. 2.68V which is after the cell protection should have kicked in. I'll let it stand for a few minutes then see what the voltage recovers to. 2.86V - even gives some usable light though I suspect, not for long.