Very High Output Light Batteries Question

Due to the very high current drain batteries needed for rated output are ultra high Lumens lights all headed for the use of proprietary battery packs? I note that the Acebeam X50 and X75 both use such packs as does the Fenix LR60 and even such an oldie though still current light such as the Nitecore TM28 is very clear about what the requirements are for the batteries needed for the light to reach maximum output, and their extended battery for their TM series lights is a sealed pack with a claimed eight 18650 batteries equivalent internally.

Based on their ridiculous capacity claims and low prices I doubt that many of the 18650 and 21700 batteries listed on Amazon would be suitable for the true high output lights currently being sold. To keep customers who need or just want the light output of the monster lights happy are we headed for proprietary battery packs throughout the industry for these lights?

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You don’t need a proprietary battery pack for lumen monsters. I have a HaikeLite HK08. That has 4 user replaceable 21700’s. 1lumen mesured the HK08 at ~60,000 lumens at 30 seconds (turbo holds ~60 seconds) with 40T’s. They also were able to charge the light at 85 watts. So, you don’t need a proprietary battery pack, but companies make more money that way. Also, the batteries used in proprietary battery packs are normally disappointing. 40T’s and P42a’s are used, instead of newer batteries.

I think the big challenge for development in lumen monster lights is cooling. At a certain point the light needs active cooling, and that’s a jump in complexity and cost. Batteries aren’t really a limiting factor.

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And what happens to both the light output and batteries if the light is fed something in the way of many of the junk cells that are out there as far as output and safety are concerned? Even years ago Nitecore warned of possible incorrect operation of Turbo mode in the TM28 if fed with batteries with inadequate current capacity. I bought a couple of laser pointers last year and they came with 18650 batteries that weighed about 1/2 that of name brand batteries and yet claimed a capacity of 6800 mAh, a obvious total fiction. As a knowledgeable light hobbyist you know about high drain batteries requirements but based on the reviews I see on Amazon praising under $30 junk lights claiming 1 million lumens output most consumers are woefully ignorant of such matters.

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James_C, I agree that this is a problem as noted in the 1Lumen test of the HK08 as referenced by LightThrower in his post. There is a reason that light has a handle complete with switch as it is needed based on reported light body temperatures reached in high output testing. Those type of temperatures are not too good for the batteries either.

I note after a bit of searching that Nealsgadgets lists the Molicel 21700 P42A 4200mAh 45A Battery in the button top format as 1Lumen indicated is necessary for the HK08 and it sounds ideal for that light and probably others but how aware of it’s even existence is the average high lumens output light user? Does the HK08 manual thoroughly cover the requirements of batteries needed for optimum performance of the light?

I think of these items as I worked in quality assurance and reliability testing for years at a Xerox subsidiary in Silicon Valley.

The influence of battery choice on light output is illustrated by the post 8/8 by cannga in the following thread. Different batteries provided 800 lumens versus 500 lumens in his test. Cheaper no name lithium ion batteries typically have higher internal resistance, limiting current output.

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Most definitely and that’s why I often listed outputs according to battery. Such as the list for the high power lights HERE. For example:

NIGHTWATCH CHAOS
Throw 754m
Output:
Nealsgadgets “Mystery” Lishen “LR2170LH”: 29300 lm
Molicel P45B 26900
Samsung 30T 25800
Samsung 40T 22900
Molicel P42a 22600
Convoy Liitokala 19300
Wurkkos 5000 mAh 18800

The Nealsgadgets “Mystery” Lishen LR2170LH (mystery because for a long time we didn’t know what it was) is essentially unobtainable unless you buy lights from him, and capacity is IIRC ~3000 mAh, so IMHO the best all around, number one battery to buy is Molicel P45B, extremely high output and 4500 mAh tested HERE on BLF.

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Thanks for the input cannga! I would love to see the actual capacity and current capability for the claimed 9900 mAh 18650 batteries listed all over Amazon’s listings for 18650 batteries. One reviewer found that when tested they were about 1/9 the claimed capacity. The no name 18650 batteries though seem to have pretty much taken over Amazon’s 18650 battery listings. The bad has driven out the good.

I think that this example and cannga’s linked to post justifies my original question regarding proprietary battery packs as with the junk replacement batteries currently on the market from multiple sources, the light makers have no means of controlling what is placed in their lights by customers and light performance is highly variable depending on what it is fed. How many flashlight and battery buyers though are as knowledgeable about these matters though as many members here?

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Although many enthusiasts wrinkle their nose at the concept of proprietary battery packs, thinking they doom the light to obsolescence once they fail, they do have an advantage for very high current series/parallel arrangements for high output lights like the Acebeam X75. Robust internal hard soldered connections and balanced charging circuitry all integrated makes for optimal performance with ease of charging.

A well maintained pack should last more than 5 years of use and if and when the pack fails, chances are the evolution of emitter and battery technology over that time will render the entire light obsolete anyway.

The Nightwatch Chaos is a one of a kind beast. It demands at least 60 Amps at full output which exceeds the capacities of the most robust cells. It needs those bespoke 3000mAh Lishen cells to reach peak output and with that relatively small capacity (to allow the insane current) so its overall runtime is quite short at anything more than moderate output.

The absolute gold standard reigning king of high current 21700 cells is the Molicel P45B, soon to be eclipsed by the 5000mAh P50B. One step down from that is the mighty Samsung 50S, another 5000mAh 21700 with a 35A rating. These 2 cells are the high current/high capacity “have your cake and eat it too” champs for high output lights. You need not look further.

A bit of advice, AVOID all ebay and Amazon battery sellers like the plague. They are flooded with Chinese garbage inflated rating cells. Only buy from reputable suppliers like 18650batterystore.com, liionwholesale.com, illumn.com, imrbatteries.com, and batteryjunction.com. Stick with Molicel, Samsung, Vapcell and Keeppower and you cant go wrong.

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Also, for your edification refer to the battery ratings and performance reviews by the esteemed fellow Mooch.

The information hes compiled is absolutely gold.

FB link: Redirecting...

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Thanks, pretty much what I figured but good to know. What is your current recommendation for high performance 18650 cells, both protected and unprotected as I have multiple older lights that require button top 18650s.

Batteries haven’t matured much for flashlights. They’re predominantly borrowed from industrial and EV use or power tools and we get to use them only because third parties can get them from the manufacturer and resell them to us as loose cells.

That said, the highest preforming batteries I’ve ever seen are sold by Neal Zhang at Nealsgadgets with the Nightwatch NS14R and A15. They’re probably rewrapped Lishen cells and are between 2900 and 3100 mAh. I tested the ones that came with the oeiginal NS59V1 at 2990 and 2899 mAh after a deep discharge and the NS14R a little better. The A15 cells came in around 14 Ah (for 3) after a runtime. These will happily chug along for a good while at nearly 30 amps a piece and take 60+ C temps. The closest competitor to these is the Samsung 30T. Even the P42A or P45B cannot compete for outout (in my testing real-world not on a bench).

For 18650, the best I’ve ever used are the Panasonic/Sanyo 18650GA, Sony VTC6, and Molicel P28A.

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IMO the biggest reason for battery packs in lights like X75 and X50 are not the cells themselves, but arrangement. They want to use cells (and likely LEDs) in series to get more power without dealing with ridiculous currents.

Because to get 80k lumens at 3v with LEDs/cells in parallel current will be ridiculous and it will reduce efficiency significantly and require driver which can handle such current.

And once 4 cells are in series it requires a BMS and they have to make it a pack, especially companies like acebeam which sell in retail and can not just say that if it blows up it is user’s fault.

BMS? Is that shorthand for a Battery Management System?

A parallel arrangement with modern LEDs and current levels would also require pretty large gauge wires too to manage the current without excessive losses and potential heat generation. Even the Nitecore TM28, a now 7+ year old design though still being made, apparently runs up to 40 amps from it’s 4 batteries in parallel based on Nitecore’s listed requirement for 10 amp continuous discharge rated batteries for full rated turbo output which is still only 6000 Lumens claimed, minimal by current standards.

Yes. Have to monitor individual cell state for it to be safe.

I am pretty sure something like x75 would be completely impossible with parallel arrangement.

80000lm with quite generous 150lm/w would be what, ~530W, ~150A at 3.6V, ~180A at 3V? Even at 20000lm it sustains current will still be very high…

At this current everything becomes an issue - springs, any contact points, wires, PCB traces, transistors used to switch all this, etc. A bunch of extra losses and heat generation everywhere.

But at 14.4v (4 cells in series) it goes down to the same ~40A you’ve mentioned which is much more manageable. Though it does require quite good cells…

Basically the same reason why power tool manufacturers go for higher voltage and packs too. And USB charger standards are switching to higher and higher voltage. Higher voltage means more power can be practically used without dealing with impractical currents…

And it also means new fancy 46800/46950 cells and lights with them will have to deal with certain limitations compared to multiple 21700/18650 lights…

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Is this the ball park figure for most flashlights? Including my small Convoy lights for example?

As i said - that is very generous. Realistic for efficient low CRI high CCT emitters and efficient driver only.

High CRI emitters, especially at low CCT, can go well below 100lm/w even by themselves, before considering driver efficiency. There are some awesome emitter tests around here, you can use those to roughly estimate what to expect from lights with specific emitters.

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It would rewire more current than that. Closer to 220-250 amps at 4 volts provided you used 3 volt xhp70.3. the A15 from Nightwatch claims 270 amps on turbo with fully charged batteries. Plus voltage sag after 90 seconds or less even with the fan on might trip LVP with all but the highest performing cells even in 4P so they’d tune the firmware to step down aggressively. This is why the A15 stinks for sustained output and running with aggressive (totally impractical) fan cooling drops the runtimes significantly and even then only managing around 9,000 Lumens max.