Have never used a 2x18650 light before and heard both batteries should be at same charge before placing in the light? Is this correct? part of purchase decision would be occasional disaster/emergency use( frequent floods and hurricanes with lengthy power outages in my part of the world) so a possiible scenario is having an odd number or randomly charged batteries on hand if things drag on. Is it safe to just insert and use them?
Using multiple18650 lights safely
- Thread starter mickb
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MAD777
Flashlight Enthusiast
NO NEVER, DON'T DO THAT!
For my multi cell lights, I buy them as a set (same supplier, shipment, brand, model, etc). Then I label them with the flashlight name and 1 of 2, 2 of 2, (or 1 of 4, etc.).
They are then Siamese twins. They get used together, charged together, stored together, etc.
If one gets damaged, they both get thrown out.
Don't be this guy...
For my multi cell lights, I buy them as a set (same supplier, shipment, brand, model, etc). Then I label them with the flashlight name and 1 of 2, 2 of 2, (or 1 of 4, etc.).
They are then Siamese twins. They get used together, charged together, stored together, etc.
If one gets damaged, they both get thrown out.
Don't be this guy...
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Why not just use the one in a single cell light?
StorminMatt
Flashlight Enthusiast
I don't go so far as using matched sets in multicell lights. Rather, I do runtime tests and measure voltages toward the end. When I know how long I can run the light, I just run it for a somewhat shorter period of time to give me a margin of error. Also, even though I don't run matched sets, I still keep all my cells the same in terms of model (ie all NCR18650GA, all VTC6, etc), all fully charged at the beginning, and all roughly the same age (ie not mixing a new cell with one three years old).
ven
Flashaholic
Just throwing a thought out here, instead of 2x 18650 fed lights that dont seem too suitable for your uses. How about a 26650 fed one, up to potentially 5200mah , built in USB rechargeable. Output wise around 2000-3000lm. Check out Olight and Acebeam offerings if may suit............from xhp35 HI( usually throw biased)xhp50(bit of both:naughty: ) xhp70( usually flood bias) in the newer offerings available.
Other than that and want to stick with 18650, have a spare matching set of 2 ready to swap out and rotate. Not ideal for the cycle life having a couple of cells sat there for an unknown time, but when needs must they will be available with pretty much full charge. Ideally dont leave for a year+, try and use them, even if it means for 1/2 hour then top off every 3 months or so.
Other than that and want to stick with 18650, have a spare matching set of 2 ready to swap out and rotate. Not ideal for the cycle life having a couple of cells sat there for an unknown time, but when needs must they will be available with pretty much full charge. Ideally dont leave for a year+, try and use them, even if it means for 1/2 hour then top off every 3 months or so.
Thanks Ven I will look at the 26650 also. Would be after a moderate thrower that beats say 40 lux but trying to stay under 2000 lumens and closer to 1000 would be preferable for battery life. I will check out those offerings you mention.
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MAD777
Flashlight Enthusiast
One of the ones ven mentioned, Acebeam EC60, would fit your desires nicely. It's one of my favorites.
ven
Flashaholic
+1
You can run it on L4 at 1200lm, no need for turbo mode if not needed(turbo is just a short use/burst/wow mode anyway due to heat limitations and also............ manufacturers bragging rights).
Hi mick, you can check out the Convoy C8 its a single 18650 light but it is definitely a thrower, or you can get the Convoy L2 which is a 1 - 2 x 18650 / 26650 cell(s) gives you the option to choose the cell configuration. I have both lights and both are throwers with the L2 beating the C8 by a small but obvious amount of lumens.
Hello Nick I myself own a nitecore P36 needs 2 18650 cells with button head I put in Flathead cells without protection sometimes I put in cells which I have recycled from old laptop batteries the only danger you can encounter is that you have to self and one cell has a low capacity that the load capacity cell will discharge itself below 3 volts so this cell can go to the recycle bin but it is also very handy to keep all cells standby in case of a total blackout it is always better to use cells which you keep in pairs of 2 but I like my light running on unprotected Quality cells which are only $5 each greetings from Netherlands
Thanks gents for the added suggestions and advice. Can I ask another question and that is when 2x18650 batteries are run in series does it increase run time for a given output? That is if I were running a single 18650 1000lumen light and extended it to 2x18650 do I get twice the run time, or any more run time. Or are their other factors at play?
StorminMatt
Flashlight Enthusiast
Usually, runtime is increased but not doubled. The reason for this is that with one 18650, the light will fall out of regulation at some point and start to dim somewhat as voltage drops. When this happens, current draw drops, which extends battery life. But this doesn't happen with 2x18650. If you are running an emitter (or emitters) with a Vf in the 3's and a buck driver, the light will NEVER fall out of regulation with 2x18650. It will continue to run at full power the entire discharge cycle while the current draw actually INCREASES with time. This will suck down cells faster.
Right. On the other hand, if the two 18650s are in parallel then it's basically like you have one battery with twice the capacity and the runtime increases. I've also heard that sometimes it increases by more than a factor of two because less current is supplied by each battery so it's less stressful on the batteries.
ven
Flashaholic
A good advantage with dual cell lights(other than the higher output ) is the ability to run at a higher output for longer. To keep simple, say a single 18650 light is usually 1000lm on turbo, maybe good for 3-5m before stepping down. A lot of dual cell lights are 2000lm, these can run at 1000lm levels for a good bit longer due to the extra mass(heat dissipation) and sustain for longer run times due to the extra tank(cell).
Blah, a good example would be the tk75 run time kit, this more than doubles the run time with 1 kit due to spreading the load over 8 cells, than just the 4.
If power cuts are frequent and maybe several days long at times, then (obv many other bits of kit come into play) a 4 cell type light(maybe pop can) gives great run times on lower modes. They may have a 6000lm wow mode which is useless other than 30 second scans(example), but to run at lower levels gives days of use. Where a single cell light would offer less light(ceiling bounced for an example) for less time overall. Of course we can have spare cells at the ready. But for ease, a multi cell light on lower output levels can come in very useful. For just one example would be a thrunite tn36(MKR), this on moonlight mode at 1.6lm(roughly) can give a nice soft light in a room with night adapted eyes...................for a month!!!
Just rough examples, but for higher outputs for long duration's(500lm + for an example) then dual cell lights would be a better choice over single for heat and run times. Which ever light or size of, always worth having a back up(might need to find fresh cells for the light your depending on). Or it could fail, get lost/misplaced ............ So no matter how expensive, good,reliable a light is.............it can still get lost/misplaced and still fail!
Blah, a good example would be the tk75 run time kit, this more than doubles the run time with 1 kit due to spreading the load over 8 cells, than just the 4.
If power cuts are frequent and maybe several days long at times, then (obv many other bits of kit come into play) a 4 cell type light(maybe pop can) gives great run times on lower modes. They may have a 6000lm wow mode which is useless other than 30 second scans(example), but to run at lower levels gives days of use. Where a single cell light would offer less light(ceiling bounced for an example) for less time overall. Of course we can have spare cells at the ready. But for ease, a multi cell light on lower output levels can come in very useful. For just one example would be a thrunite tn36(MKR), this on moonlight mode at 1.6lm(roughly) can give a nice soft light in a room with night adapted eyes...................for a month!!!
Just rough examples, but for higher outputs for long duration's(500lm + for an example) then dual cell lights would be a better choice over single for heat and run times. Which ever light or size of, always worth having a back up(might need to find fresh cells for the light your depending on). Or it could fail, get lost/misplaced ............ So no matter how expensive, good,reliable a light is.............it can still get lost/misplaced and still fail!
If you use protected batteries is no problem.
In time the batteries will not have the same capacity even if you use in the same light, charged together, will appear some difference between them in time. The protection circuit will always save you.
After 20-30 charges the batts will not have identical capacity. So use protected batteries and all be ok ( in the pasta I used one protected Eagletac + one protected Panasonic, different capacity, different age in a Nitecore MT40, I had no problems when one of batts was empty ) .
I don't recommend Acebeam EC60, too much money for what you get, instead you can look for example at Nitecore EC4GT , nice regulation, is not hot even after 10 minutes on turbo
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Thanks Octavian that is good to know.
Regards the EC4GT which looks interesting, wondered if I could ask a couple of questions?
Are these batteries in paralell or series, though they are physically paralell, one youtube review said they are series?
I notice you commented on this review. http://www.candlepowerforums.com/vb...EC4GT-(XP-L-HI-V3-2x18650-or-4xCR123A)-Review
I am just trying to make sense of Candle Lamps graph for non fan cooled regulation. Looking at the graph is it saying no fan and its automatic drop to 55% output for the whole duration of Turbo ??
Can I also ask how quickly light turns on using the on switch. While its not obviously a tactical torch is the on/off function instantaenous?
Thanks!
