Any flashlights with battery status indicator?

Just wondering if such a feature is available? It would be nice to know before the output drops...

There are various sears craftsman lights that used to have a power meter on them. Surefires unreleased optimus and invictus will probably have a small lit indicator, though no one really knows how it works(full low dead? something else?). What I'd like to see is a tailcap for surefire 6P/C2/etc with a battery indicator light for the folks who use rechargables, would be a great feature to have

The soon to be released Surefire UA2 and UB2 have one.

The LiteFlux LF5XT has one but I'm not sure about their other products.

the LiteFlux LF5XT and not sure about other liteflux, has a battery voltage check function which tells you the voltage in X.X Volts in the form of flashes.
Also Olights have a low battery warning which flashes a few times when the battery is low.
I know there are a couple other brands/lights that do that as well but i cant quite think of them.

All LiteFlux flashlights have a function that tells you on demand the status of the battery. I have also to say that reading the answer is easy enough but asking the question is a bit difficult.....

You have to perform the by now famous SW operation five times (SWx5) and then the light starts flashing and gives you a direct voltage measure e.g. two flashes, pause, nine flashes = 2.9V

I've read somewhere that the new Surefires will use a 3 color LED, which I assume would read green (full), yellow (depleted) or red (low). I'm interested to find out how accurate this will be since estimating the remaining power for Lithium primary cells should be done under load (like with the ZTS line of battery testers). I'm pretty confident that Surefire will do this the right way, so I suspect the indicator will light up while the light is in use. Another light that does this is the Petzl Tikka XP headlamp.

The various other lights out there that can flash out voltage I would think are most useful when using rechargable Li-ion cells. In that case, the "resting" voltage is a good indicator of state of charge - ie, 4.2v = full, 2.9v = dead.

It takes 2-4 seconds to 'ask the question' on a LiteFlux and about another 15 seconds to complete the 'answer.'

You have to access this function to get cell voltage. If you have the light's over-discharge protection function turned on, it'll blink to let you know that the cell is depleted and then it shuts the light off to protect the cell (for rechargeables).

Another light with an actual indicator for a low cell is the Photon Proton and the Pro. The red LED comes on when the white(s) is/are on and that indicates a low cell.

PT Apex has a tiny flashing LED that changes color (green to red) as batteries are depleted.

The best example of a battery indicator IMHO was the one that was built into the Mr. X lights. You could run the light for 45-50 minutes in regulation, but the moment the batteries couldn't keep up with it, a small red LED near the mag switch would come on alerting the operator that the light was now shifting to direct drive.

So far, I haven't seen any light that has anything close to as functional as the Mr. X version. That being said, I can't wait till later this summer to see what Surefire's version of a battery indicator will look like.

I wonder why no one has reproduced that invaluable feature from the Mr. X??? Its a mystery to me!

:thinking:

MSax

MSaxatilus said:

The best example of a battery indicator IMHO was the one that was built into the Mr. X lights. You could run the light for 45-50 minutes in regulation, but the moment the batteries couldn't keep up with it, a small red LED near the mag switch would come on alerting the operator that the light was now shifting to direct drive.

So far, I haven't seen any light that has anything close to as functional as the Mr. X version. That being said, I can't wait till later this summer to see what Surefire's version of a battery indicator will look like.

I wonder why no one has reproduced that invaluable feature from the Mr. X??? Its a mystery to me!

:thinking:

MSax

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Interesting feature but it's probably a solution looking for a problem. The second LED would only add bulk / complexity to a light and that is not what what the mainstream users would want.

The Mr X indicator sounds like an interesting feature, but I wonder how useful it would actually be with today's regulation circuits - guess I'm thinking (although this could certainly be misguided) that many of today's circuits operate from a fairly wide voltage range and in doing so are capable of maintaining regulation a good bit longer, sometimes with the disadvantage of not offering much warning before the light suddenly dims into oblivion. At least in my experience, it seems once my lights drop out of regulation, I find that I don't really have much juice left in the cell(s).

But then again, since switching over largely to rechargables, I don't often take them to that point and behavior with primaries is obviously very different.

Petzl Tikka XP headlamp has a small flashing LED on the side, it changes color from green to yellow and red (nearly depleted).

The Blackhawk Gladius gives a double flash every 15 seconds IIRC when the batteries need replacing

There is a Brinkmann available at Target that has a built-in power indicator and variable power bottons. I think there was even a review done on it.

Edit: It is a 2xD cells light.

Here is the review:

http://candlepowerforums.com/vb/showthread.php?t=193331

The Pelican 7060 blinks every few seconds when it's running low.

There are a number of flashlights including surefire lights which drop into a "moon" mode. IMHO this is a pretty good inidicator as well as being a simple solution vs installing a voltage sence circuit and LED's to show voltage...
Yaesumofo

yaesumofo said:

There are a number of flashlights including surefire lights which drop into a "moon" mode. IMHO this is a pretty good inidicator as well as being a simple solution vs installing a voltage sence circuit and LED's to show voltage...
Yaesumofo

Click to expand...

It would be quite useless. The only purpose it can serve is tell you when hit a lower voltage limit for the pack/cell so you can turn it off before you damage the rechargeable cells.

The voltage profile of NiMH, NiCd or lithium doesn't allow reliable indication of the state of charge.

The reason laptops and Sony cameras/camcorders can very accurately predict the state of charge is that it records when full charge is reached based on termination points and literally counts the amount of energy leaving the pack before you reach end of discharge termination.

It has algorithm to compensate for usable capacity change as a function of changing load, duration elapsed in storage, etc but the prediction is not perfect so you have to do a full charge/discharge once in a while, not to condition the pack, but to calibrate the meter.

As to why it isn't integrated to every device, cost is an obvious reason, but it's quite possible that it just isn't permissible due to patent issues.

bagman said:

The Blackhawk Gladius gives a double flash every 15 seconds IIRC when the batteries need replacing

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+1 for the Gladius and Typhoon. Insight Typhoon H2X is the exact same thing and much cheaper. Recently got mine new for $133.00 USD shipped. Was very easy to upgrade to a seoul U bin emmiter as well. You can also get the Typhoon H2X2 that already has the seoul emmiter in it from the factory for around $150.00. I'm a big fan of this format and UI.
Fletch