I am looking for the most mah vs price vs length. I think this one, on Fasttech is what I am thinking is my best option.
Panasonic NCR18650 Protected Rechargeable 2900mAh 3.7V 18650 Lithium Batteries.
My question is what is the actual mah? It seems like other Panasonic’s get pretty close to stated mah, so this one shouldn’t be any different, but just want to make sure before ordering several pairs of them.
And will these work for high drain lights?
Thanks………
http://lygte-info.dk/info/Batteries18650-2011%20UK.html
The guy that does all those reviews is HKJ. He's a member here. His site also allows you to compare a few different batteries.
A few? He has way more than a few on his site 
I got six of those Gray Panasonic NCR18650 2900 taken from a brand-new but old laptop batt pack I bought from Ebay. Although the lowest voltage taken out of the pack was 1.72V, when charged and discharge-capacity tested in my hobby charger at 1.5A, the lowest was a high 2874 to as high as 2925mah. Higher in percentage than the also brand-new green NCR18650A/B that are currently flooding the market today.
For the OP, the capacity is not the only thing to consider, the larger capacity panasonic batteries maintain a higher voltage for longer.
The best Panasonic battery is Panasonic NCR18650PD green.
HKJ has protected version of this battery on a test so it will not be top performer as unprotected one.
This is definitely better than Sanyo UR18650FM. I tested this in my 3A lights.
- They are providing more current to led and lux results are slightly better than on Sanyo red for longer periods of time.
- They are even smaller and lighter than Sanyo red. They doesn’t heat when charging.
- It will fit in 2×18650 lights because although they are flat top their button has enough contact with surface.
- It should take up to 10A of current
I haven’t seen review of this cell? I mean review of bare unprotected Panasonic NCR18650PD?
I’ve read rumors that it is merely an NCR18650 without the PTC.
If that is the case where are my NCR18650PD 3400mah
If someone has review link of this bare Panasonic NCR18650PD cell please link that here.
I am using some batteries now that are 69.5mm and are putting a lot of pressure on the tail cap spring in a couple of lights, and these 2900 mah are 69.2mm so thats a plus.
I was also interesting in the 3100 mah batteries but they are 69.7mm long. I know it’s not much, but it would add a bit more pressure on the springs.
I looked at the NCR18650PD but they list for $26.35.
Panasonic NCR 18650PD unprotected Here.
I like these shorter protected Panasonic 18650A . They call them flattops, but there is really a low profile button which make good contact in most lights and in series.
Bare Panasonic NCR18650PD cell is 65mm long they are not 69,2 like you said. This is true 18650 battery, and not 18700 like plenty of protected ones.
They will fit to any 18650 flashlight in a world and preserve your spring contacts.
There were some German members that were doing a lot of tests on these batteries. I have a couple of them. They are good cells.
Yes but this still looks to long for me. 4 mm longer…
Is that protection on cell really necessary if a man knows basics?
I found interesting information about Panasonic cells.
This is from HKJ so I will quote him:
“I have not seen any clones of Panasonic, but you have real Panasonic in a couple of varieties:
1) Genuine Panasonic cell, is always unprotected.
2) Modified Panasonic cell, i.e. a button top added and/or protection added. This is not done by Panasonic, but by somebody unknown.
3) Rewrapped Panasonic cell, this is the same as 2), except that somebody is taking responsibility for the modifications.
Be aware that the Panasonic 2900 cells do not hold a charge exceptionally well. A 2900 charged to 4.20, will be down to 4.10-4.15 30 days later, much farther after 60 days. Not the end of the world, but other batteries hold charges exceptionally well, like the Samsung 2600 and the Sanyo purple-ring 2800.
Someone mentioned that this issue in the 2900 can be corrected if you use the battery in a medium-drain situation where the cell gets warm because of heavy use. Not hot, but warm.
Strange as it seems, this running the 2900 battery under heavy load just once seems to help it retain a charge much better. I have some Pan. 2900 batteries now that I allowed to drain down to 3.80 over about 20 minutes in a 2.5A light. And indeed 12 days later, ALL six of the 2900s are 4.18v or above; and four are still at their original charge of 4.19-4.20. Usually— before this new sacrificial draining and warming — 2900s routinely will be down to 4.17v a few days later after being charged to 4.20, let alone retaining a full 4.19-4.20 charge after 12 days.
Once again, dropping to 4.10-4.15 is not the end of the world, but if you plan on storing your cells for 3-4 months, these 2900 batteries will probably be down to 4 volts by then. UNLESS this draining-warming routine actually affects longevity for that long, which it may.
Hope this helps!
Very interesting,
Yes it really should not be any issue since it drops to 4,15 almost instantly under higher loads(3A). I would not call that as an issue if this really happens.
I had to measure mine after your post.
I have 7 days fully charged Panasonic NCR18650PD and they are still on 4,2V so no voltage drop here for now? But I will recheck again in a week or two.
They come stock charged at 3,56V so I guess this would be ideal storage voltage for this cell?
Info like this is what I am looking for. I am wanting something protected, in the (actual) 2700-2900 mah range for the $11-$13 per pair range like on Fasttech. And not over what I have now at 69.5mm.
This is for use high lumen lights like the TK75.
Lots of variables at play here, and there are tradeoffs involved. 
If you want short cells you would avoid protected cells, and you need to monitor the cell voltage closely to avoid problems.
The “most mah” ususally comes at the cost of high current ability or voltage sag - sometimes both.
What do you mean by “high drain”? A 4A load on one cell is higher drain the same load on two or three cells.
I try to match cells to my particular application:
My house light is an XPG in a P60 at 1A on high. I just use pack pulls for this.
An older C8 XM-L draws 3A on high but is never used more than 15 minutes at a time. An Aw LMR 1600 works well.
A new XM-L2 P60 use for walks needs higher voltage and good current. Sanyo 2600’s hold their voltage longer but don’t have the best capacity. But I take short walks. :bigsmile:
My J18 wants lots of current and isn’t picky about voltage ’cause it’s a buck driver with three cells in series. Some Pana PDs worked well until I got some KKs.
My point is that it’s almost impossible to get the highest current, voltage and capacity available in one package for a reasonable price. I think you’d be doing well to get two out of three. Someone already suggested using HKJ’s cell comparator, and I second that. It can help you pick horses for your courses.
I just received 4 x Panasonic NCR18650PD. They were all exactly 3.55V.