IMREN IMR 32650 3.7v 5000mAh Li-Mn Batteries, opinions?

I just ordered 2 of the 26650 hosts and 1 with heat sink from budget beams and I have been searching for the best 26650's.
The NUBM44 and 07E are power hungry and even my LG inr 18650's are lacking runtime unless I run 4 in series parallel.

I ordered these:
2 Green Efest IMR 26650 50A Battery 3 7V Rechargeable Li MN 4200mAh w Free Case | eBay

I am trying to read but not finding much about if there are any better, I have heard about AW cells but they spec out much less.
Has anyone done any real testing on 26650's ? Did I overlook a thread?

I bought a bunch of 32650's to use in a project and changed my mind, now I want to run four 18650's in parallel, or even series parallel using battery extender modules for the Fenix TK75 flashlight: Fenix Aer TK75 Flashlight Extender Tube with 18650 Battery Holder | eBay - I can get more capacity out of four 18650's in parallel than a single 32650.

Alaskan said:

I bought a bunch of 32650's to use in a project and changed my mind, now I want to run four 18650's in parallel, or even series parallel using battery extender modules for the Fenix TK75 flashlight: Fenix Aer TK75 Flashlight Extender Tube with 18650 Battery Holder | eBay - I can get more capacity out of four 18650's in parallel than a single 32650.

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From what I have been reading the 32650's have not caught up yet, but as the vaporing masses need more power to drive basically a dead short, that is their glowing red hot shortened nickel chromium coils to vaporize their nicotine juice the battery manufacturers have been mass producing improved formulations such as IMR and INR for the 18650, but the 26650 has taken hold and they are being mass produced with the newer formulations as well.

The 32650's seem to still be using the old formula.

If you are driving 4 of the 7475's then INR 18650's may be enough but you will recharge more often than with 26650's, that's why I'm switching over.
p.s. I'm looking forward to seeing your build, I'll just follow the bright green glow in the sky.

Oh Ok, I just looked at the link, yes if that holder holds 3 18650 cells then that will do the trick and it won't have to be as long as a broom stick LOL

The Fenix TK75 holder holds four 18650's, but not all four in parallel, two x two in series-parallel, so the output is 8.4 VDC for fully charged batteries and 2X the current of one battery. I am considering putting four sections each containing 4 batteries together for what I want to do, that's 16 batteries at 8.4 VDC (since the way the holders are wired they add current, not voltage when stacked). So, the current capacity will be 8X that of a single battery, in that case. If using 3500ma batteries, the total capacity would be up around 28 amp hours at 8.4, that's a whole lot!

I am communicating with two people here who build hosts and trying to get this kicked off to have two of them built, neither exactly the same, but both to build knife edge pointers. So far no work has started on either project by either machinist. Not sure how soon my project will be done, or even if I can get this built, I'm probably pushing the capabilities of both machinists with this big guy, while I have not been denied, I fear they might not take the work on, sadly. If I have to take this to a local machine shop I'm afraid the cost will be far too high, Alaska machine shops charge a premium because they have more than enough work in this town.

Alaskan said:

The Fenix TK75 holder holds four 18650's, but not all four in parallel, two x two in series-parallel, so the output is 8.4 VDC for fully charged batteries and 2X the current of one battery. I am considering putting four sections each containing 4 batteries together for what I want to do, that's 16 batteries at 8.4 VDC (since the way the holders are wired they add current, not voltage when stacked). So, the current capacity will be 8X that of a single battery, in that case. If using 3500ma batteries, the total capacity would be up around 28 amp hours at 8.4, that's a whole lot!

I am communicating with two people here who build hosts and trying to get this kicked off to have two of them built, neither exactly the same, but both to build knife edge pointers. So far no work has started on either project by either machinist. Not sure how soon my project will be done, or even if I can get this built, I'm pushing the capabilities of both machinists with this big guy, they might not take the work on, sadly. If I have to take this to a local machine shop I'm afraid the cost will be far too high, Alaska machine shops charge a premium because they have more than enough work in this town.

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Its a great idea for providing lots of amps and keeping it hand sized.
I thought you were going to use the accompanying housing as well, it will be more expensive but maybe not as much as having 1 made.

You could go with 3 26650's and a Chinese driver that will work between 7 and 18 volts and drive your diodes in parallel like they do in projectors, I don't like all my eggs in one basket but it's an option. I have been looking at many slightly larger drivers on ebay that are not designed to fit in an ink pen.

As far as machining goes I would think someone here could do what you need.
I used to work in a machine shop and they had a pair of 3 axis cnc's and a couple manual mills, but it's been years and they may well have 5 axis machines by now. It's a mom and pop and they would probably be willing to do anything you needed but you would need to have exact drawings of what you want.
Actually I could see if Mark still works there, he went to school with the owners son and has been there forever, he runs the cnc's and if so you could probably deal with him online as he is always willing to hustle a buck.

I would think someone here could do what you need, I have seen people advertising for work even and a lot of the parts you need can be bought online.

http://www.ebay.com/itm/Knife-Edge-...-DPSS-Laser-/131507871267?hash=item1e9e7ade23

At this point, I am starting to think just buying a TK75 flashlight and removing the LED lights and having a knife edge heatsink made for it might be the least expensive way to build one, since the battery compartment is the larger challenge for the project due to my wanting to have so many big batteries (assemblies) in it. Another issue was finding a switch which could handle 20+ amps, I have that solved though, using a driver which can be controlled with a low current TTL input voltage to turn the diodes on. I think I will stick with individual drivers for each diode though, donno, I could always change my mind on it I suppose but I really like the idea of keeping the voltage at 8.4 VDC, I see no reason to regulate 12VDC down so far to the diode operating voltage and waste all that capacity as heat, except to reduce the number of drivers which I already have in hand anyway.

Maybe I will wish I had three sets of batteries in series for 12V if I find the batteries drain too fast, but these TK75 battery holders don't add voltage by stacking, due to how they are wired inside. There is a battery holder I think is fairly ideal requiring very little modification for stacking three sets of four 18650 paralleled batteries in series, it is part of a Niteye EYE40 or EYE30 flashlight, I have two sets I bought from HKEquipment some months ago, I recently tried to buy a third and they are no longer selling them separate from the flashlight, tried several other sellers including the manufacturer and they just ignore my emails.

TK75: http://budgetlightforum.com/node/40917

http://www.candlepowerforums.com/vb...650)-Review-RUNTIMES-BEAMSHOTS-VIDEO-and-more!

A buck driver wont waste all the over capacity in heat like a linear driver.
But I think the upper limit is 12 volts not 12.6 so I don't know that you would want 3 lipos in series.
Lazeerer builds the SXB, he can answer your questions.

I was told by a seller that the SXD driver can take a maximum of 18 VDC, is that not accurate?

Alaskan said:

I was told by a seller that the SXD driver can take a maximum of 18 VDC, is that not accurate?

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Huh YES I had it wrong.
I just checked and it is 18v max, somehow I thought it was 12v not sure how I got that in my head.
Thanks for straightening me out on that. Being able to run 3 rather than 2 18650 or 26650 in series will solve a lot of run time issues.

I was hoping it would give more run time, but if a problem, I could always put a dummy battery in series to reduce it to just two batteries in series at 8.4 VDC charged. There is also the possibility of running two NDG7874T diodes in series with a single driver running with 3 batteries in series from 11 when drained, to 12.6 VDC charged, but the run time would be shorter.

Alaskan said:

I was hoping it would give more run time, but if a problem, I could always put a dummy battery in series to reduce it to just two batteries in series at 8.4 VDC charged. There is also the possibility of running two NDG7874T diodes in series with a single driver running with 3 batteries in series from 11 when drained, to 12.6 VDC charged, but the run time would be shorter.

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Put 3 cells in series to power your heat sinked driver and drive a 1 ohm load in place of your diode and monitor the amperage out ,voltage drop and runtime as well as driver heat.

I think you will find you get longer run time and not too much more heat.

You can try it with 2 cells in series i.e. 8.4 then 3 and even 4 because as you said the upper limit is 18v so 4 cells is 16.8 max at full charge.

My only concern was the driver pot settling in after adjustment, someone brought up proper heatsinking, but because my driver was stable with my heatsink and the only change I made was a pot adjustment then I can't very well start blaming the heatsink as it was never a problem.

This is where I would settle it in with the 1 ohm test load before powering my diode. But maybe that's just me and DutchLaser that had any issues with that and after a couple cycles it settled out fine.

Anyway you can use the 1 ohm load to test 2,3, and 4 cell configurations and determine what will work best as the 1 ohm load simulates the diode.

100W 1 Ohm Power Resistor Wirewound Aluminum Housed | eBay