In the dark about remaining charge?

Hi everyone, I haven't popped in for a while but I've recently become re-inspired to get something off my chest.

I have become more and more convinced that the lack of a charge indicator in consuming devices is unforgiveable, and can only be explained by laziness or cheapness.

I can't be the only person who resents carrying a spare battery 'just in case' the one in the flashlight is low. It means toting a second, somewhat fragile item, when I really only need the primary tool (which is plenty rugged for the task). Battery management is all very well for regular users - you know how long a full charge gives you - but I have several flashlights in several places, and tend to just grab the nearest when I'm heading somewhere that might be dark. I have NO idea when I last changed its battery, or how much use it's had since then - let alone whether that use was on a high setting or not. It's a crapshoot. I really don't want to have to remove and test (or swap) the battery EVERY time I grab a flashlight and head out, so instead I end up grabbiing a fresh battery, or risk running out of light mid-task.

I have tried (and conceived) a number of different systems to try and solve this, ranging from custom holsters with spare battery compartments, to flashlights with switchable parallel power sources (ie a 'reserve tank'), but at the end of the day the best solution is clearly an onboard charge level indicator of some description.

I realise that yes, flashlights are available with charge indicators. But the vast majority don't, and I wonder why not. It seems like such a no-brainer. The technology is already in so many other battery-powered devices, why not flashlights? Is it too hard? Too bulky? Too expensive? Has it just not dawned on manufacturers (and users) that it would be a really, really useful thing to have (in fact, perhaps more useful than a hundred different strobe modes)?

Or is it just laziness and cheapness?

I'd be interested to know if anyone has a compelling reason for NOT including a basic battery level indicator in a ~$100 flashlight.

Interesting premise. One of my flashlight, an HDS (more than one HDS) is in a holster with a spare battery compartment built into the holster. Nothing to worry about here. When I take out lights with rechargeable cells I usually switch out for a freshly charged one. No big deal on my part, and I am lazy too. I do have a battery carrier that I can fit one 18650, four AA's, four CR2's. or three CR123's that I can carry if I am going to be out for awhile.

Bill

How would the battery level indicator appear in such lights? Are we talking a LCD screen with information like on battery chargers? Are the current battery level warnings in most lights not enough?
Would it blend with the design of the light? Would it affect the toughness, durability, etc of the light? Why would anyone be out without a spare battery?

For such a light,either a battery voltage mode similar to the Nitecore EA4's blinking indicator would be enough for me but I'd like to use the primary emitter to do the blinks, instead of a fragile screen or another led at the side.

RobertMM said:

For such a light,either a battery voltage mode similar to the Nitecore EA4's blinking indicator would be enough for me but I'd like to use the primary emitter to do the blinks, instead of a fragile screen or another led at the side.

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+1 on that
technology is available, so it would be nice if more lights had the voltage-check built-in.

Yes, such a feature would be really nice in all lights. I don't have very many so I'm currently able to keep track of all the lights pretty well (and I usually bring spare batteries), but I can imagine trying to keep track of a few more could turn into quite the chore. It would at the very least save some time so I don't necessarily have to get out the multimeter when I come back from a trip.

kj2 said:

+1 on that
technology is available, so it would be nice if more lights had the voltage-check built-in.

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Agreed!

I have a brinkman 2D 3 watt LED Digital Flashlight.
It has a four button waterproof panel and screen.
2 buttons work the up and down brightness modes
1 button is a battery test
1 button is ON-Off.

The panel/screen shows the battery strength (like your cell phone) (when tested, or while the light is powered on.
It also shows 1-4 bars of light intensity mode.

Very simple, and helpful.

I have no problem if my light has a battery level indicator. Do I really need this feature? I would say no. Whenever I go out, I just put a freshly charged cell(s) to my light and carry 4 fresh primary cells.
I EDC a HDS Hi CRI (with a SF with Malkoff M361N as backup), so I can tell when the battery needs to be replaced.

It would be nice but its not needed. For those times I know I'll be using a light I just top off the battery before hand and Im good to go. For those times I dont know I'll be using a light, chances are I wont need long run times and the battery is still good to go.

There are lights that have voltage indicators, the TM26 for example has a digital display that says the charge, and the remaining run time at whatever brightness you have it on, etc.

Buy a TM26, and your problem is solved.

Meters make a lot of sense for Li-ion consumer electronics like cellphones, tablets, laptops which are integrated in terms of dedicated device/battery/charger - this complete integration is also what makes them safe for the average layman to use without all the Li-ion knowledge and rules we flashaholics need to abide by (don't overcharge, undercharge, mismatched capacity used in series, etc.). The circuits and software handle all the details for them. The chemistry also lends itself to accurate meter readings with an even, steadily sloping discharge curve.

Flashlights are quite different in that they can usually accept a wider variety of battery chemistries (each with different voltages), and configurations (eg, single 18650/multi CR123) and some of those chemistries (lithium manganese dioxide and NiMh) have incredibly flat discharge curves lending themselves to false meter readings of remaining capacity. How many different battery chemistry/configs options can a meter be accurate with a light that supports a 3-9v range?

Then the current flashlight battery meter technology seems to require electronic switches (I just don't know any mechanical clickies with a meter) which have parasitic drain, and are an additional point of failure that cannot be easily repaired or field by-passed. Although it should takes months, or years, for the parasitic drain to deplete a cell - I anecdotally read about enough post where cells are draining in days/weeks (perhaps just faulty).

When a light supports a single Li-ion cell, like an SC600, then the meter will work great, but you lose the back-up option to run primaries. But in another broad voltage multi-cell light, like the SC52, the meter only seems to work well with 14500s - NiMhs show 75% full when only 25% is left (a function of the cell's flat discharge curve) and the idiot-proof auto step down means the light won't support the 3V CRAA.

I prefer a meter-less, broad voltage AA/14500, mechanical clicky light with a good moonlight mode, for which I can find AAs anywhere, including cannibalizing cells from another AA device I'm usually carrying. Except for protected Li-ion's, I can use a max/high comparison to determine when the cell is nearing its end and stick to the energy conserving low and moonlight (my most often used modes anyways). I also carry a piece of MacGyver tinfoil so I can use a AAA/9v and anything between a CR123 and 18650 in a real pinch... this cell versatility constitutes near unlimited runtime for me. Course, like many others, I also carry a back-up keychain AAA or two .

A guy who finds using a meter on his cells or carrying spares, to be an unacceptable burden is unlikely to think that even more prep is a solution though.

Not a burden, just unacceptable limitations for a marginal benefit for me. Spares? I EDC plenty, they're just occupied in other devices serving other purposes.

reppans said:

Not a burden, just unacceptable limitations for a marginal benefit for me. Spares? I EDC plenty, they're just occupied in other devices serving other purposes.

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Lol

Not you, the OP.



He didn't want to carry spares or use a meter.



All he has to do though is buy a TM 26 though. ...Easy enough.

TEEJ said:

Lol

Not you, the OP.



He didn't want to carry spares or use a meter.

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Hehe....Oops

But it did apply to me as well... I don't like carrying [dedicated] spares nor having to open my light for batt tests, or changes. I guess the big difference is that I'm sub-/low- lumen, night vision, runtime nut that rotates one light at a time - so I just meter my 1x14500 weekly, and charge/change it every three weeks (that's about at about 40 hrs usage, or 2 hrs/day).

I see theOP's point. How many out there would buy a cell phone that you had to take out the battery, test, and place into an independent charger as compared to just plugging it in? I think we'll see more and more hand held flashlights with not only charge indicators, but also without any specific sized battery, just cells that can be recharged. Not those $50 two million candle power spotlights that are all over the place. But quality lights that have the output and runtimes of the indepent cell lights most of us have.

LGT said:

I see theOP's point. How many out there would buy a cell phone that you had to take out the battery, test, and place into an independent charger as compared to just plugging it in? I think we'll see more and more hand held flashlights with not only charge indicators, but also without any specific sized battery, just cells that can be recharged. Not those $50 two million candle power spotlights that are all over the place. But quality lights that have the output and runtimes of the indepent cell lights most of us have.

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I suppose if cell phones used interchangeable cells instead of dedicated power packs, it would be relevant.

The key, for me at least, is that if the cell has to be in the device to charge it, I am out of action during the recharge.

If the electronics are flexible enough to tell me what the dmm would have, and durable enough to not be the weak link, and reasonably priced. ..why not?

In practice, adding a dmm to a flashlight tends to add vulnerability and cost....but, for some people, I could see it as an option.

As there ARE lights with this feature, the end result of whether they SELL or, end up on the clearance rack, will be if the feature is as important to THEM. If so, more lights will follow suit.

If they languish on the shelves, makers will drop it from the features list.

TEEJ said:

I suppose if cell phones used interchangeable cells instead of dedicated power packs, it would be relevant.

The key, for me at least, is that if the cell has to be in the device to charge it, I am out of action during the recharge.

If the electronics are flexible enough to tell me what the dmm would have, and durable enough to not be the weak link, and reasonably priced. ..why not?

In practice, adding a dmm to a flashlight tends to add vulnerability and cost....but, for some people, I could see it as an option.

As there ARE lights with this feature, the end result of whether they SELL or, end up on the clearance rack, will be if the feature is as important to THEM. If so, more lights will follow suit.

If they languish on the shelves, makers will drop it from the features list.

Click to expand...

Fine point , but I just see the trend of everything having to be easier to use with less and less hands on, figure it out by yourself type products. It's just the way things go. For instance, how many out there would know how to clean, if they knew what one was, a carburetor.

reppans said:

When a light supports a single Li-ion cell, like an SC600, then the meter will work great, but you lose the back-up option to run primaries. But in another broad voltage multi-cell light, like the SC52, the meter only seems to work well with 14500s - NiMhs show 75% full when only 25% is left (a function of the cell's flat discharge curve) and the idiot-proof auto step down means the light won't support the 3V CRAA.

Click to expand...

What about a voltage flash system like the Nitecore P12?
(5xflash/pause/2xflash=5.2volts)
That would work with any cell combination and chemistry.

I would love a simpler way to determine charge left in cells without taking them out. I'm on board. Only caveat is I want it to fit retroactively on the lights I already have.