Why do you recommend the Sanyo FM? Because it is the better choice at 3A…?
In the 5A and 7.5A diagrams the PD is the best…?
In the last third the -FM has a higher voltage than the -PD. But you are right, I should have said it differently and therefore edited my post. I'll explain:
It all depends on the light. I have single cell lights exclusively. Now if you are like me or mainly use single cell lights, the 3A and 5A discharge curves are those that matter.
Triple or quad XPGs might pull up to 5A while still having a relatively low vF of about 3.2V @ 1.5A if I remember correctly. In the last third of the discharge curve, the Sanyo -FM is still well above 3.2V while the -PD isnt. Also, most people already have Sanyo -FM based cells while the -PD is rather new.
So if you wont draw more than 5A from one cell, the Sanyo -FM is still great.
These tests were all made with unprotected cells, right?
I looked a lot at the discharge curves from HKJ and recognized that protected cells have lower voltage curves, it seems they are just shifted parallel a bit down.
Yup, all unprotected. Protection lowers the voltage quite a bit due to more resistance. The more amps you draw from a cell, the higher the difference will be.
Will the Samsung cell vent when abused? As in, will it be have like an IMR? Thanks
Well, they are IMR cells. No regular cell would hold such a high voltage under load or even get through that without melting. For example, the Panasonic NCR18650E rated for 20A got so hot at 20A that the shrinkwrap around the negative terminal crumpled.
The Samsung -20R is UL listed and used in some power tools made in Germany.. so I consider them as being save. ;)
Thanks for the response!
When you do these discharge tests, do you usually log temps as well?
I didnt do them and no. But touching the cells after discharging works well. :D
Is it UL tested so far?
I thought that this will come later this year…?
I assumed it. An engineer of a well known German power tool brand told me that they have to use UL certified cells if built in Germany. Maybe he was talking just about an internal "law" in his company?
Will you write up a regular review test thread of these new Samsung INRs?
What do you mean with regular review test thread? The guy that tests them for me has nowhere near the equipment HKJ has. So all I have are discharge curves. We might publish an IMR shootout in the future, but some people were interested in the new Samsung cells. And because the recent king of IMR was AW I decided to share a few curves upfront. :)
Ah, ok, the discharge curves are very confusing, 20A 2Ah, 7.5A 1.3Ah? etc.
I just asked HKJ some minutes ago if he could test it. I will get one myself but I can’t test discharge much or make curves.
Yeah, I put a value wrong when plotting the 7.5A curve. Fixed it now, thanks for pointing that out. What else is confusing?
Oh, if you can regenerate them, use a single axis scale, so all graphs have the same X and Y values, min, max, step.
I guess that was the only one wrong. 5A seems correct I think maybe tiny bit lower than 7.5A, who knows. 10A seems longer than the previous two.
Hmm I guess just sort out the X axis values, put them true, not fictional 
I prefered the fictional X-axis, but I changed it so you can compare them better. Also added 15A curve.
Thanks.
I just bought one. I would suggest if anybody wants these, probably jump on it.
They were $6.50 and got sold out. Asked to have them relisted, waited a day for IS to get another order confirmed and these went up to $8.89 with shipping, after they sold sold 63 pieces in one day.
Wrote them I’m not going to buy it for that price since they have been much cheaper especially when I want just 1 piece. Got them discounted to $7.49 with shipping.
So if anybody wants one, go ahead, I don’t know how long they will stay cheaper.
They do make packs/add solder tabs for free as well if you want to make yourself a pack for some device! Which I find a really great option.
$7.49 Samsung INR18650-20R 20A 2000mah 3.6V Li-ion Rechargeable
They also have the lower rated 20Q version with “only” 15A rating. In my opinion they are probably 2nd tier batteries, you know, Samsung sorts batteries based on internal resistance or something, some factor that determines how hard discharge they can handle.
$6.95 Samsung INR18650-20Q 15A 2000mah 3.6V Li-ion
Second cheapest source if you want just 1 battery is here, paypal and shipped as well:
8.22 EUR Akkula.fi Samsung INR18650-20R
Will post my low amperage test once it gets here.
_
BTW there are also 13R and 15R versions that have lower capacity but some are rated up to 25A. They are on eBay too.
Samsung’s description of the various batteries.
13Q and 15Q are rated 18A, also on eBay.
i bought the “20R” from the same guy at 16/02 for 6.50 now they have for 6,99 still good price.
$7.49 with shipping. Yes they had a really good price for them for some time.