there is absolutely no information on testing conditions for battery runtime
like
at 21°C
ENERGIZER L91 Ultimate Lithium
Constant Current Discharge to 0.8 Volts
Now, as I mentioned before , I did not expect the XTAR to get 80 hours runtime on a 2000 Mah eneloop , but I surely expected to get longer then 28 hours runtime. That is a big difference between the companies claimed runtime, and actual runtimes . And we now can see, the company was not claiming 80 hours runtime, on special lithium batteries, because they list nimh/alkalaine as being used . In fact, I will be shocked if this light got close to 80 hours runtime, on a new alkalaine. Maybe thats why it was marked down to $7.50.
correct….it doesnt even mention using lithium battery….therefore you conjecture that the 80 hour runtime, is accurate because the manufacturer is claiming use of lithium, is wrong. the runtimes were for nimh/alkaliane.
now can we admit you were wrong, and / or the company is being deceitful at best ?
Gestestet mit einem 750 mAh NiMH Akku und der mitgelieferten Alkali-Batterie. Die Brenndauer im 100 Lumen Modus ist akkumuliert, da die Taschenlampe nach 3 Minuten Betrieb im 100 Lumen Modus zum 25 Lumen Modus herunterschaltet, dann aber wieder neu mit 100 Lumen aktiviert werden kann.
Contact Xtar and ask em which battery they used to get the runtimes I am almost sure they did it with a Lithium primary
if you got a XP-G R5 LED inside you reach about 150 lumens/watt at low currents
so your NiMh has 1.2V and 2000mA that is 2.4Wh on paper
a Lithium primary has 1.5V and 3100mA that is 4.65Wh on paper
so 3 LED lumens x80 hours are 240Lh
so I need just a bit over 1.6Wh to power the LED the rest taked the flashlight converter
3.05Wh from the lithium primary are lost in the converter
34,4% efficiency
if you get only 30 hours out of your eneloops
that means from 2.4Wh are only 0.6Wh used to power the LED
so 1.8Wh are lost in the converter
25% eficiency
There is another thing to consider, which is how much charge is lost while sitting on the shelf. I use NiMH rechargeable batteries in many things. I recently bought a (16?) pack of eneloops and recycled some old Energizer’s.
HOWEVER, all of my devices that are strewn about the house for emergency use, have Energizer Lithium primary cells installed. In many cases I have also fashioned insulators out of old business cards that prevents each device from accidental turn on or any standby drain.
I have not run any tests to determine max run time for any of my emergency devices. I do have spare Lithium primaries and multiple methods of charging batteries from virtually any power source. I’m confident that I could easily go months without requiring new cells to generate light. But then I don’t live in a cave where I need a light on 24 hours a day either.
The eneloop , I used for this test…was fully charged at a slow rate…capacity read 2019 Mahs….it was then put right in the light, and turned on moonlight mode for testing. This eneloop, did not sit on a shelf for days or weeks, where it would lose capacity. I did this test, because I actually thought it would be incredible, if the XTAR got anywhere close to the 80 hour runtime as claimed.
you dont u8nderstand that testing conditions are not specified
and the battery type to use is as well Lithium primary but as it is not common they did not write that in the description so people dont put 3.7V batteries inside
no matter how you try to spin it, this is deceptive on the companies part.
If you bought a car, and they told you it gets 60 miles to a gallon ….but then you got it home, to find out you only get that MPG by using jet fuel…and if you use normal gas, you only get 20 MPG….and you werent told this by the manufacturer…would you feel deceived ?
For moon light or low low light, your best bet would be a alkaline. The Engergizer L91s have not performed well at lower levels. Edit, well for the money
How many light you plan on having on at once ?
Have you ever used a light camping?
Sounds like you just want a light left on in each room?
Compare the reported runtimes from the various reviews to (2nd page of results) what Gerber claims.
It won’t last as long as the manic pixie fantasy flashlight claims, but then, nothing will.
It will last a long time, and it will slowly get dimmer as the voltage drops.
One key point on low level light —- don’t turn it on and off, just leave it on. Just starting up the driver electronics will consume more of the remaining battery power than you save by using it intermittently in moonlight mode, according to Gransee of Arc Flashlight years ago.
PS, since your stated need is for a light that will last several days —
— do you mean 24 hour days, like in a storm shelter? Or will you have daylight every day?
— do you mean only when you’re in the room, and awake, or 24 hours per day?
If you look for emergency lights you’ll find a variety that may do what you need.
Try www.dorcydirect.com and consider their motion sensor battery lights and emergency lights.
If this XTAR would have gotten 60% of its rated runtime of 80 hours, with my eneloops, I woulda been happy. Only getting 28 hours out of a rated 80 hours, is quite a difference. I was expecting to get around 55-60 hours runtime , so I am dissapointed , but its no big monetary loss.
Ill probably just wait till a good sale comes for what I need or new technology comes out in 2017 to get the longer runtimes on moonlight mode using eneloops.
I did not want to have to buy all new batteries . I like the eneloops and their performance overall. I still think the XTAR suffers from severely over rated specs and this is to be expected for a $7.00 light.
[quote=hank]
PS, since your stated need is for a light that will last several days —
— do you mean 24 hour days, like in a storm shelter? Or will you have daylight every day?
— /quote]
Yes….this would be for a storm shelter type deal or power grid down for several days
Thats why im so dissapointed with the 28 hour runtime from XTAR.
I liked the idea of having a simple , inexpensive LED flashlight that runs on a single eneloop AA/AAA , for 2 days or more, on moonlight mode, using a light diffuser.
Well… theres really only one way to find out. Just get an alkaline cell and try it out. Not all alkaline batteries are created equal too. Some are longer running than others for low drain applications. It would be presumptuous to just assume a product doesn’t meet Akaline spec without actually testing.
The other aspect you are neglecting is the discharge characteristics of Alkaline versus nimh. Alkalines at very low current gradually deplete their output. So at these low currents its not always cut and dry. Oh also, eneloops may not be actually 2000mah. My understanding is they gradually lose capacity, especially when they are repeatedly deep discharged way down. So there can be a lot of variables.
Anyways… For whatever reason, ultra low candle modes (fraction of a lumen) are almost always not featured on budget-affordable lights.
The thrunite T10 has a .2 Lumen ultra low mode from a 1.2V battery (presumably an eneloop pro). This might get you to 80 hours and with a 240 hour spec I would fully expect it to.
I just got a TH20 headlamp. Its spec reads, With AA 2450mAh (eneloop pro I would assume) = 14 day run time at its .3 Lumen firefly mode. This headlamp has replaced my $$$ Zebralight and I am very impressed with its overall quality for the $ spent. I would expect similar levels of quality from the T10.
Anyways… Good Luck!!! At ~$8 I still think you got a GREAT light for the money.