I somehow find it useful on 10180 keychains although it increases size. 10180 chargers are pretty rare so internal charging seems to be the only option. Charging port is in the treaded part of the head so it does not compromise water resistance. On the downside the port is mini-usb rather than type C, probably due to size constraints.
I also have a regular 18650 light and feel absolutely no need for a built-in charger.
I like onboard charging, some do it better than others like Olight or Imalent with their magnetic charging. I think it’s good to never have to open up a light unless it’s for replacing a battery, makes them more waterproof etc. It seems with my little light experience that achieving a 2m IPX-8 waterproof rating is not comon with light that have USB connectors under little rubber plugs. I guess it depends on your expectations and what type of light.
A minority for certain. I have a newish unlocked Samsung Galaxy Xcover Pro. It is also a rugged phone. Some mil-spec number. IP68
I think USB charging on a battery is more important than USB charging on a light.
Unless your flashlight uses a sealed design like iPhone.
Except EDC flashlight 
I wonder why it gets so little attention. Polarity doesn’t matter, charges LiIons and NiMHs, can always be with you on a journey. Cool little thing.
I’m wondering if people who would rather set their hair on fire rather than buy a light with onboard charging, have any phones, tablets, earbugs, powerbanks, anything that has and requires usb charging.
I’ve got lights that don’t have any built-in charging, those that have usb charging (micro and C), and those with magnetic charging. Each has pros and cons. But the biggest pro is choice.
I like onboard charging simply to not have to dig out a charger, whether my little LK or big honkin’ Opus. And in a pinch, I can swap cells from another light to charge that cell.
I’d also rather just use usb charging to not have to wear out the O-rings unscrewing/rescrewing the tailcap to get at the cell. And if I “wear out” the usb port, I still have the option of external charging.
Hell, I even topped off my lights on a bus on my way to/from work. Plug right in, vs juggling the light, tailcap, cell, charger, and cable, fumbling around and risking dropping some or all of it.
IMHO I’d rather have a phone with an easy removable battery. It’s a bonus if I can get a charger for said battery.
Yeeeeeeeah, that’s not gonna happen.
My old Note 4 has a replaceable battery and I have once. That doesn’t mean I want to remove it every time it needs charging.
Choice is a good thing no disputing that. For me though, as far as flashlights go, that choice comes with drawbacks for something I really would not use often enough.
Generally I do not buy electronic devices that only allow on-board charging of sealed batteries. I will always try to find another competitive option with easily replaced batteries. If there is no other choice, then I buy whats available. I sit here and type this response on a $$$$ macbook pro that has seen the bottom aluminum chassis slowly bowed outward from what I suspect is an inflating internal battery. It’s a leased computer owned by my employer. I have an appointment to have it checked out at the apple store later.
My personal laptop is an HP touch screen running widows 10, with a removable battery. I like that much better… thats why I bought it.
USB charging circuits have gotten extremely compact and advanced, and they can provide safe charging just like an external charger when designed correctly.
They are basically no different than an external charger, it is still just a microcontroller that adjusts the charging voltage and current.
The difference is no display for battery analytics and possibly lower charging rates.
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Ideally the light will still have a removable battery for either:
A) you need to keep using the light so you carry a spare charged battery to swap it out in a few seconds
or
B) you have an external charger and prefer using that to charge faster or to see detailed info
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If the light does not have a removable battery that would suck, especially since there are high end Li-ION options that you can replace the stock battery with for better performance.
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As for waterproofing, USB C is waterproof if you buy the waterproof version of the port. So that is a non-issue.
As for dirt getting inside, most lights have a rubber flap to cover it, or they hide the port behind the threads so the light needs to be slightly opened to plug in a charger.
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The main advantage is being able to carry the flashlight WITHOUT a bulky external charger and still be able to recharge it if it runs out.
Taking a flashlight to work, school, camping, travelling, etc. is something I do often but I never want to also carry around a large square Li-ION charger.
If I have a small square phone charger and USB C cable, I should just be able to use that to charge the flashlight in the rare occasion it runs out of battery.
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With USB PD up to 15 and 20V it should also be possible to charge larger flashlights now, not just single cell lights.
Even small cube chargers can now do 20W and are only 1” cube.
HKJ has done testing with examples of the variance in cell quality and in charging quality - http://www.lygte-info.dk/
I absolutely wouldn't want on board charging unless it is absolutely necessary for the intended function of the light, implemented properly, tested to verify that it is operating correctly, and from a manufacturer with a reputation and history of good quality control. For instance the BLF LT1 would not be as functional without on board charging, but it was done well. There are too many extra opportunities for problems to happen and too many manufacturers that cut corners with QC for me to say I am for onboard charging in general. I just carry an extra battery or 2.
I am for removable batteries in cell phones and still daily use my old S5 with a removable battery where the charging port has failed, and I remove the battery to swap it out when it gets low. It gets annoying, but I am glad I have that option, and eventually I'll get around to replacing the charging port on the phone. One huge caveat to cell phones and laptops using onboard USB charging are that unlike other USB charging devices, they use computer controlled and monitored charging with much stricter QC than any flashlight that I have heard of. I don't entirely trust the quality of my external phone battery charger, but I have verified that it slightly undercharges the cell and charges very slowly at a low current, so the cell never gets warm.
Just my preference, but I won't gift a Li-Ion light(and a tested, reliable external charger) to anyone who can't be bothered to treat the cells with the care they warrant and who hasn't been informed of the difference between Li-ion and primary AA batteries etc, and safety in handling them. I don't want to contribute to someone being injured or killed from a lack of understanding or from a manufacturer who puts profits above quality control and safety. A few years ago in a city near me, there was a little girl who was killed and her siblings severely injured in a fire caused by a "hoverboard" and the dangerous implementation of Li-Ion power where catching fire was so common that they were banned from being sold for a time and removed from store shelves if I remember correctly. Many clear cases of manufacturers cutting corners on safe implementation of Li-Ion and in quality control.
There are also reports, though rare, on BLF of people who have had cells charging externally, and they exploded, but if I remember correctly at least one case was a cheap 14500 ****fire cell. ***Edit I found it: https://budgetlightforum.com/t/-/11570
For anyone interested, another good source for everything battery related including info on variances in chemistries and on the charging of Li-Ion cells is https://batteryuniversity.com/index.php/learn/article/charging_lithium_ion_batteries
Multicell arrangements NEED an actual BMS, with taps at every cell-to-cell junction to monitor everything. So no way would I want a multicell light that claims to have onboard charging. Let’s get that out of the way. (Vaguely recall on the amazon-deals thread, a light was exactly that, a 2-cell light with onboard charging. Yeah… no.)
That said, I think what’s getting everyone’s panties in a knot is assuming (or demanding) that every charging circuit in a flashlight should be as rigorously designed as a dedicated external charger that can be cranked up to 18W or more, that monitors temperature, resistance, everything, and of course that’s never gonna be the case.
Especially when people demand C-to-C charging, so a flashlight can be used as a f’n powerbank and charge a phone… c’mon! Don’t be ridiculous. Spend the 10bux and get a f’n separate powerbank…
Onboard charging should be thought of as an “emergency” (or at least convenient) way to top up a light without needing a dedicated external bulky charger. No QC3 or PD or whatever, to fast-charge the cell so hard that you’d need to monitor the temperature. Just a simple stoopit way of feeding it a trickle at 500mA or even 1A, so that a 3000mAH cell could be good to go in 6hrs/3hrs or so. Ie, plugging in your light while on a car trip, or plugging it in overnight at a hotel, whatever.
Plugging into a 500mA-limited laptop port, I even charged decrepit laptop-pulls without one so much as getting warm. Same cell charging on one of my headlamps (think it was a D25, not sure) from a cube-charger started getting warm enough that it warmed the light itself.
Point being I slow-cook all my cells ‘cause I’m not in any itchin’ hurry to push the limits of the chemistry seeing how fast I can charge a cell. And I never had a problem.
So… every light with built-in charging that you get, throw in a few cells and immediately on indicating a full charge, pull the cell and measure its voltage. Do it a few times, freshly-turned and then let-sit for a while. A charger that cuts off after a full charge will probably show a few mV lower after sitting, which is good. Just make sure that the cell never sees more than 4.20V, and you can pretty much safely charge any quality cell that you feed it. I do the same (if I remember) even with cheepcheepcheep come-with external chargers, too.
Throw in a 9990mAH Crapfire cell to charge, and it’ll do the same whether it’s in an external charger or inside a light. So going supernova in an open charger is somehow “better” than inside a cell? They both go boom.
A flashlight should be a flashlight. Not a dedicated charger. Not a powerbank. Having simple onboard charging is a huge plus to pretty much any light (except diving lights and the like, of course).
Q: “How important is orange peel reflector?
A: “I would never buy a light with OP reflector”
A: “OP reflectors are dumbest idea in flashlights”
That’s kinda how I read the question and answers. On host USB charging is a design feature just like any other design feature of a flashlight. It’s useful to understand and consider all the pluses and minuses, and to flush out misconceptions.
On-board charging doesn’t really add much weight or size. Electronics are pretty small these days. It’s hard to square the “I don’t want the extra weight/size of onboard charger” and “I always carry my external charger / extra battery” as the same use case. The point is, different use cases, different feature sets.
Regarding the quality of the charging circuits themselves, they can be as good as the “good” external chargers. You can go out and get yourself a crappy external charger, just like you can go out and buy yourself a light with crappy onboard charging. The quality of the charging circuit is not inherent to whether it’s external or built into the light.
There may be more serious consequences to overcharge when it happens inside a flashlight. I’d be interested in really understanding what would happen. Would it act like a pipe bomb? I’m not sure. People seem to think onboard chargers are leaky enough to pose a water ingress issue, but also well sealed enough to be a pipe bomb? Those two ideas don’t square.
LB, if I understand your comment on charging multicell lights, you don’t recommend it? What about SP36 and the like? Always thought you were for it. Maybe you are referring toseries cells?
+1
Thanks Lightbringer, I thought that clarification was missing from the thread, but it makes for a lengthy post.
Context, perhaps, is important to this question. Specifying use by or gifting to noobs who might treat an 18650 like an AA and/or manufacturers with poor QC records vs quality on board charging used by knowledgeable enthusiasts with quality cells and reasonable charge rates makes a big difference. Being that this is an enthusiast website, I would think we would be talking about the latter, though use is becoming more widespread by the former. In that latter case I’d think about buying a light or 2 with on board charging for camping or backpacking perhaps if I needed it, though I would still use external charging most of the time. Personally, it would have to be from a manufacturer with a very good QC record or return policy though, if it would be cumbersome to replace a faulty charge board.
fourbyfive earlier had asked about reports of fires during charging earlier, not to imply that on board charging vs external matters for a cell that explodes. Past my bedtime and I forgot to cite. lol
I’ve got some ancient sanyo laptop pulls that are starting to get uncomfortably warm even when charging at 300mAh and are begging to be retired. I imagine they might cause a problem if someone left one of them charging at a high rate on the dashboard of a car sitting in the summer sun. But that speaks to using quality batteries and watching out for old cells that are getting close to retirement age.
Correct. Never ever ever try to charge a 2S/3S/etc. light without a BMS.
In parallel, though, you can mix panny-Bs with 30Qs with 10180s, again, all in parallel, and they’ll all maintain the same exact voltage across the lot, drawing only as much current as each individual cell wants.
The CC phase divvies up the current amongst all cells, each one only getting a proportional amount. The CV phase just finishes off the bunch, never exceeding 4.20V (or whatever’s the CV-voltage of the charger).
I mentioned before that as much as I like the BLF Q8 (warmer, floodier), my desktop light is my DC7, which is cooler and throwier, but has onboard charging. That convenience trumps the beam quality, sadly.
The light in question was a 2S plunger light. (Bah, looked, can’t find it anymore. Maybe a different thread…)
Same here. My Q8 gets little use compared to SP36. Just easier.
FWIW the usb-c charging socket on my Fenix PD36R seems good enough. My cheap multimeter read the charged voltage at 4.12v. I can’t see it being a problem in the rain, it’s on the underside of the light so even if the rubber seal failed rain is unlikely to get inside. It wouldn’t have an IP68 rating if it couldn’t actually be underwater for 30min without being damaged.
IP ratings are self-reported by the manufacturer. With Fenix it’s probably accurate.