Battery information you may want to know

Don't know if this has ever been posted before but while searching around for batteries that can handle a serious current draw for some PT-121 Phlatlights I found this site. Before seeing this I had already purchased 6 Samsung 25R besides already owning a lot of other high drain well known cells such as Pan Pf and Sanyo along with lots of Efest stuff. Have a pair of the Sony VTF4 on their way also from a legit place also. Basically about 6 months ago I decided I would rather give up some capacity for cells that could handle a bigger load as the hobby is quickly ramping up with newer and much more powerful diodes.
Anyways you can see a lot of information here on cells you commonly use and they focus particularly on the Samsung 25R in the main page with the information I really wanted to know (checkout the pulse specs on them). Difficult to explain how staggeringly bright at 25A a green PT-121 is (and the in-rush current is 27.1A)
Towards the bottom there's the information on who rewrapps their cells too. It is a very good read.

Best 18650 Battery

Make sure you scroll over if you have to so you can see all the information as they have data sheets you can click on. Matters depending on what you are using to view the site. Do wish all the data sheets would show the pulse information for everything. You have to search harder to find the specifics like how many seconds at 50A type stuff.

Here's another great link and within the first post click on the things that start with "here's the chart for...".
https://www.e-cigarette-forum.com/forum/threads/comparison-of-vtc4-vtc5-lg-icr18650he2-and-samsung-inr18650-25r.592339/

Thanks Pman! That's a good comprehensive site, it's nice to see most everything on one page.
Definitely going to bookmark this one for reference. :yh:

Very nice dude.. Thanks

I also found some info. on the Sony VTC4 (I hear there's also a 5 that has 500mAh more out too) that states not only the 30A continuous but they can also do pulse at:
35A = <80 sec.
50A = <60 sec.
60A = <30 sec.
80A = <15 sec.
That's some serious draws.
If I didn't make it clear enough this research came about learning about the possibility of running PT-121 Phlatlights at full output capability without what would likely be a very expensive driver direct through a properly rated switch keeping in mind its a shock and awe short run time kind of thing. A lot of these heavy load batteries were developed from my understanding from the needs of the sub-ohm vaping community where some are using them all day long at .04 OHM and even less.
I don't know how often the site updates but it also has good references to click on. It is information from the beginning of 2015 so it's valid for us today.
There are only 2 used PT-121 greens left on Ebay from the seller that I have purchased 3 of them from for just over $20 shipped in the US. I've never seen any others sold unless you look at $100+ for a new one. I purchased 1 at least a couple months ago and it looked like new but also experimenting bought 2 more which will arrive next week.
With 2 Samsung 25R in series the voltage will drop to 5.7 and will pull the 27.1 A in-rush and basically start slowly dropping the V and A. Looking at the data sheet this is pretty much the max which should be 5000lm and it really is incredible. Keep in mind we are talking the color green here and I couldn't imagine being on the receiving end.
Regardless of how I found this information I hope this helps others out for whatever they are buying/building.

PMan ;

Having abused many 18650 cells in RC racing, I would caution everybody on using the pulse ratings on the cells tested. Every manufacturer would say DO NOT use them at those peak current levels, because of heat rise internally and possible venting/fire.

Maximum continuous current rating should be what is used in any high-output design.

I built a few PT LED lights and heat dissipation at the LED was the limiting factor.
This is a 50W UV light I built with two pounds of aluminum:


That being said, I do like the new Sanyo NCR18650GA cells for their combo of 10 amp continuous draw and 3500 mah capacity.

We have a fresh shipment on the way to Dallas.

Absolutely. I would caution anyone/everyone also about this. Practically everything we do here is a risk assessment and the individual must assess where they are at. There are users that want nothing to do with anything over 5mW and I respect that.
When I am experimenting I take other precautions such as was the case with the PT-121 testing where I enclosed the batteries inside a metal toolbox before hitting the switch. That used PT-121 green took a 1 second hit of 47A with 2 paralled sets of 2 series cells (8.4V paralled) and I can see no damage with a 10x jewelers loupe and then re-ran with the single set of series cells and got the exact same readings before I hit it. The point was not really to see what the amp draw would be as I knew it would be significantly more but to see how robust the LED was.
Some of the sub-ohm vaping I've been reading about puts a much harder load on cells than one of these LED's. It would be absolutely wonderful if a proper driver was used not only for something like this but what the vape community was doing.
That being said, I can't disagree with you on the panasonic and sanyo cells. I have a large number of them and they are a great compromise between the 10A rating and the high mAh and for the moment fit well with the current crop of diodes. A lot of people buy the B type cells when I would recommend the 10A ones at this point. I've bought cells from you. Did not know there were ones rated at 3400mAh now at the 10A. What are the b type cells rated for now as the panasonics I used to buy were that 3400mAh I believe?
The Samsung and Sony cells are something I got into from experimenting with PT-54/121 and they have a lot less capacity. I just don't use my lasers like others do. They sit in cases 99% of the time. Not very concerned with on cycle.
Maximum continuous of the Sony are 30A. Other than faulty cell or fake battery the LED should blow before the battery and I will reiterate that I am NOT after a long duty cycle with the way I am using them. I buy them from reputable places and check against the information out there for counterfeit and have run all my cells that are awaiting builds through my OPUS BTC-3400 V2.2 to verify capacity and internal resistance . Fake cells seem to be sold everywhere now and I've found myself edgy about it so I do some basic tests before use.

The original green NCR3400B Panasonic cells were rated @ 2C or 6.8 amps.

The brand new Sanyo cells are 3500mah, AND have a 10 amp rating.

That is a 47% increase in current rating and more capacity.

I also have some of the Samsung 25R cells with higher current ratings,

but much less capacity.

Here is a photo of a PT-54 Red light I built in a brass pill for one of our members (Daguin) :

^
I've been reading through this also:
Types of Lithium-ion Batteries ? Battery University
Very interesting stuff as I do own a plug-in Prius. No $ for a Tesla until publishers clearing house comes to visit

I've got a project box with a couple of high draw 18650 in parallel and high amp switch for a wack of about 650lm with that PT-54 red according to the data sheet. What driver did you use for that? The same one Jayrob used or something else?
I believe I purchased a set of the Samsungs from you as a special request
The seller only has 2 greens left. Mail was way late today but I received my second one today and it looks and acts like new. One more to come next week. Couldn't resist before they are gone.
I have tested the reds and blues also real quick but I didn't write anything down yet as I was distracted by the green.
When running the red and blue I parallel 2 18650. I think you can get about 850lm out of the blue and over 2000lm on the red but I would have to test and check the data sheets.
I'll point out that I never mix and match cells and all of my lasers and lights have their own batteries. Probably have a couple 100 cells. Rather insane.

Pman said:

^

What driver did you use for that?

I believe I purchased a set of the Samsungs from you as a special request

When running the red and blue I parallel 2 18650. I think you can get about 850lm out of the blue and over 2000lm on the red but I would have to test and check the data sheets.
I'll point out that I never mix and match cells and all of my lasers and lights have their own batteries. Probably have a couple 100 cells. Rather insane.

Click to expand...

I used a 3 amp driver as customer wanted continuous operation capability.

From using lots of 18650 cells in stressful applications, the best method for matching cells is Internal Resistance with your cell analyzer/charger.

I have gone thru ~500 cells in various projects.

Thank you for the link, great information. After reading about what is out there, their pluses and minuses, I'm very interested in the LiFePO4.

I use quite a lot of LiFEPo4 instead of 10440 and 14500 in units that don't require the extra voltage of a standard lithium.
Larry, after I got the Opus I began writing the internal resistance on the cells in perm marker.

New technology by Sanyo/Panasonic NMR cells lower the Internal Resistance . . .

allowing higher current capabilites . . .

both for discharge and charging.

Amazing 260Wh/kg Power Density

Are you going to run it DD single cell? Ive hooked up my PT-54 to a single cell VTC5 and after 30 seconds the cell gets pretty hot. You probably want to put 3 cells in parallel or get 2 in series with a bucking driver. The leds get very hot too

The green PT-54 I have is from Jayrob and is a complete build that runs off of (2) series Feilong unprotected 6000mAh cells with a driver and has about a 1 hour run-time so that's not an issue.
I have a red PT-54 in a project box with a 30A switch that I don't think I've never ran more than 10 seconds on that has (2) High continuous discharge rated cells in parallel for about 650lm. If I remember correctly the amp draw is about 13 but I can't find the paper that I had with the voltage sag. That 54 red is strictly a flood as I took of the lens. Have one set up with a lens on it and original heat-sink and another 3 complete ones. Just see my sig for the list of them all. Don't know how I ended up without a blue PT-54 but I'm looking for one even though they have the least output.
Everything else is just high max discharge rated cells in (2) cell 18650 battery boxes either run in series or parallel with 30A 12V switches. Yes I have paralleled those setups also to test Amp draw/voltage drops/sag but doing so will cause a large swing in amp draw and you may blow the LED. Need to look at the data sheets on them. I blew one PT-121 blue with a stupid mistake of paralleled series (4 batteries). Running series cells with a blue 121 pulls 32A at 4.2V.
The ratings on batteries are very dependent upon the "C" (temp) rating and I have NEVER run any of my tests long enough to more than just slightly warm a cell. Heat is the enemy and messing around like this you are stressing the batteries, decreasing life and capacity. NEVER mix cells and match them first as close as possible to their internal resistance. It can take quite a few cells to match especially as you get into the parallel/series game. Don't just throw all your batteries together and grab whatever of the same kind especially if they have different usage. It's a very good idea to have a plastic box with compartments for keeping the cells matched with their partner. You can of course label them with permanent marker which is usually easily removed with isopropyl alc.
When I first posted this stuff I was just giving a very basic reason why I had started to earnestly look into what the "real" deal is with batteries and how to reduce the risk as much as I reasonably could in my testing. I really hadn't intended to get into all this though in this thread but it just came out and I understand why there have been concerns/questions.
I'm going to add a couple more links for some other testing I ran into as even though I have some 30A+ rated cells that site recommending the Samsung 25R as a great overall battery for higher drain devices is some wise advice.
Here's the link though for those who have already been here and wouldn't read the first post again:
https://www.e-cigarette-forum.com/forum/threads/comparison-of-vtc4-vtc5-lg-icr18650he2-and-samsung-inr18650-25r.592339/
Also click on the links that start with "here's the chart for..." in the first post for some great information

I am NOT Mr. "battery" but the information is there in a way that isn't overly complicated. Does anyone doubt that we are on the verge of 10A plus driver/diode draws? Wouldn't surprise me at this rate to see them by this same time next year or sooner plus more and more members are getting into multiple diode builds. There's a ton of info. from other sellers and forums and individuals with flashlight and vape builds with crazy power. You just have to search around a bit and discern what is legit.
I apologize for anyone thinking I'm trying to push anyone else into doing anything dangerous. I have very high quality meters and before becoming medically disabled I was a Nuclear Reactor Operator for 10 years in the USN working with electronic and very high voltage/Amps and then was a commercial/industrial refrigeration tech for 17 years constantly working on very dangerous equipment both physically and electrically. I would never claim to be comfortable around any of it (and I would say your fooling yourself if you claim to be) but as anyone knows who works with electricity you get in the game or get whacked.
It's not only about getting an electrical shock but there are a lot of VERY unsafe multimeters out there that if you are on the wrong setting or you flip through a setting while your probes are attached will cause the meter to explode (not kidding). I young new guy was working with me once on something else (but not within my site) when that very thing happened to him. He got lucky and it just scared him.

If you want unbiased third party reviews of cells, there's this guy (HKJ) over at candlepower forum, who does them. Very indepth reviews with graphs of performance at different amp loads, etc.

His site is:

lygte-info.dk


http://www.lygte-info.dk/info/indexBatteriesAndChargers UK.html


His native tongue is Danish, and there's a Danish version too.