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"Spica" - My 455nm Nichia Custom by Badboybilly

RedCowboy

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The NCR18650GA at 3450mAh (probably highest mah you can get right now) do extremely well,
internal resistance is on par with VTC6 30Amp 18650's and doesnt seem to drop too fast driving at 4.5A.

44/47A's that drive 5A+ for 8W and higher will need the 26650's definitely.

Looking at the Panasonic 18650GA cells they say 10a discharge and don't say anything about being IMR/INR formulated, actually they are ( LI-ion ) the EFest 18650 IMR are rated at 20a for the 3500 mAh 18650 size cells that are IMR and for the 3000mAh 18650 IMR formulated cells are rated at 35a discharge, they are ( LiMN ) which will be slightly less capacity but have a higher discharge rate with less voltage sag.

Typically the higher capacity ( mAh ) will not give as much current without voltage sag, however the IMR/INR formulated cells can give a higher discharge current without as much voltage sag, but they have to give up some capacity for the higher discharge capable IMR/INR formulation. The trade off is well worth it in cases where minimum needed voltage is near normal charged voltage.

If you get good results with the Panasonics then great, if not you may want to try a higher discharge rated cell, but don't go by the mAh rating, that's just the battery capacity, go by the formulation when your normal charged voltage and your driver minimum Vin is close, that being typically 2 x 3.7 ( 7.4v ) and driver cutoff ( 6.8v ) Granted your cells will float at 4.2 fully charged, but you may need to recharge before they expend anywhere near 3450 mAh because of the driver cutoff.

This is not a critique but an effort to share useful information for all readers to consider, I personally have gone with 3 cell builds for 4.5a LD demands, but if you don't have a long duty cycle or lase a lot then you may be happy with just 2 cells, you can also go with a higher discharge rated 18650.

https://www.ebay.com/itm/2x-PANASONIC-SANYO-NCR18650GA-3500mAh-3-7V-Li-ion-Rechargeable-Battery-JAPAN/121655067899?hash=item1c533504fb:g:dw0AAOSwBLlVWfkQ

https://www.ebay.com/itm/2-x-GENUINE-EFEST-IMR-18650-35A-RECHARGEABLE-Li-MN-Battery-3000mAh-w-free-case/371476564200?epid=2030629882&hash=item567dba88e8:g:cQ8AAOSwZQRYWy7V
 
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badboybilly

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All good info, I’m sure most have spare 18650,s to swap out though, I won’t be building 3cell housing any time soon, Maybe 3 18350, But not the other, that stubby laser I built a while back most were saying was to thick for a pointer however it did sell quick,

I’m curious if anyone has used or tested the Tesla 18650 batts! If any better!
 

BowtieGuy

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I like to use THIS site for battery comparison and reference, it contains almost every brand and size that someone may be interested in; there is a lot of good information to be found there.

Sorry for the thread hijack. :)
 

ArcticDude

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I like to use THIS site for battery comparison and reference, it contains almost every brand and size that someone may be interested in; there is a lot of good information to be found there.

Sorry for the thread hijack. :)
Word!! ^__^
 

Phenomite

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I personally avoid rewraps like the Efest and AW brands.

You'll find that linked 35A will be a 10A usually, sometimes they switch the LG that is being rewrapped so long as it has the same CD current.

I haven't scoped an sxd so I can't speak on what it pulls in peak and constant levels but I do have a large flashlight hobby (cough $ all gone) and will do the switcheroo between Samsung 30Q, Sony VTC6 and LG HG2's to see if runtimes can be extended.

I have a feeling VTC6 is the best still, new design and nice continuous 19A stats.


Edit, yes HDK or W/E his BLF handle is has a great collection of tests. I use his site regularly, it's how I picked out the diagnostic constant current (no pwm) Lii500 charger.

It's awesome!
 
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RedCowboy

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That's interesting, VTC6 says Li-ion but if you read into the specs it says: Cell designation based on IEC61960. INR19/66

So apparently the VTC6 is an INR formulation, they just list as Li-ion in the main part of the ad.

I bought some grey Panasonics that were touted as high drain a while back and claimed 10a, but the green Panasonics did not and they did sag more than INR cells, maybe the new red Panasonics are INR as they claim 10a but still list as Li-ion in the main part of the ad.

Anyway the green Panasonic NCR's used to be the gold standard and the NUBM44 strained them so I went to 26650 INR and that sagged much less, maybe the new red Panasonics are really INR as well, I did not see it in the ad, at any rate yes, the VTC6 will be high drain as they actually are INR formulated.

https://www.ebay.com/itm/2-Sony-18650-VTC6-3000mAh-High-Drain-30A-15A-DISCHARGE-3-6V-RECHARGEABLE-BATTERY/311843879022?epid=2255550840&hash=item489b57f86e:g:x8wAAOSw~HBaEoGY
 
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Phenomite

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Yea I suspect my reds are INR, I can always cook one and find out :whistle:

At least it's hard to find ICRs since people didnt like the explody bit when it's overdrawn.
 




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