NITECORE NL2150HPR 21700 Batteries. Wrapper removed and I see this...

[Laser_Project]

Is this a legit battery from NITECORE?

I took the wrapper off of one of my NITECORE NL2150HPR 21700 batteries and found this marking under it. Also, the engraved end of the battery is simply a thin piece of metal which can fall off after the wrapper is removed.

The reason I removed the wrapper is to fit three of them into a Fenix TK75 battery tube, they then slide smoothly inside the 45 mm ID tube with no wiggle room, when the wrappers were on they couldn't go in. Next, to design and fit with a battery cap to interface to the head and provide a negative return.

The photo showing the batteries sticking out of the tube is just for the photo, they are reverse of the way they would go in the tube later. The LED's will be removed from the head and laser diodes installed later.

There is another thin layer of plastic material below the main wrapper which appears to have been painted on which has a warning printed on it not to use the battery if the wrapper is removed. What is the reason? Perhaps for devices which must have the negative shell of several batteries completely isolated from one another, such as when in series with other batteries surrounded by a negatively grounded tube? Edit: Thinking more, I can see this is so and I won't be able to use these in series inside this flashlight tube due to that

Anyone have a flashlight to recommend for my laser diode modification which has a large heat sinked head on it which uses a 50 mm or larger ID battery tube to recommend? I have been unable to find a flashlight which uses three or four strings of two or more 21700 batteries in series to produce 8.4 or 12.6 VDC.

Due to the drivers I plan on using and the way I want to wire this project, I cannot go above 12.6 VDC.

 

[snakebite]

Thats a lg m50.
The warning is a CYA.
I would use caution to prevent shorts with that sleeve removed.
Thats a protection board and it looks like its welded to the side of the cell.
I would put on a new shrinkwrap and get plain old unprotected cells from 18650batterystore.

 

[Laser_Project]

Already have replacement wrappers on the way, now that I see I can't use them in series that way, at least not in a metal tube. Wanted the protection board due to using two sets of three in series but the tube is too tight, will need to rewrap and use a larger ID tube. Due to this I will need to find a different flashlight host which accepts 21700 batteries in parallel for that now, considering a large BLF.

Appears Nitecore uses LG M50 cells for their NL2150HPR batteries. Here are some specs I found just now: (cut and paste)

LG M50 has the following specs according to its datasheet (pdf):
Nominal energy: 18.2Wh
Minimum energy: 17.6Wh
Nominal voltage: 3.63V
Standard charge current: 1455mA (0.3C)
Max. charge current:
0<t<25°C: 1455mA (0.3C)
25≤t≤45°C: 3.395A (0.7C)
Charge end voltage: 4.2V
Charge cut-off current: 50mA (100mA used)
Max. continuous discharge current:
-20<t<10°C: 2425mA (0.5C)
10≤t≤25°C: 14.55A (3.0C) (added in new version of datasheet)
25<t≤55°C: 7275mA (1.5C)
Discharge cut-off voltage: 2.5V
AC impedance at 1KHz: ≤25mΩ
Max weight (w/o washer): 70g

I wanted to use these due to their 15 amp rated continuous current, cant find protected 18650 cells rated for that amount of current (except for Acebeam cells BatteryJunction won't mail to me through USPS or ship via DHL etc., which is the only way I can get them) to use in series. I could use unprotected cells, but since they would be in series, it is possible to drain an individual battery below 2.5 volts before the total combined battery voltage is too low for the device to stop working on its own..

There is a video on Matt Smith's YT channel showing a size adjustable 8 cell 18650 (or 21700, but not confirmed yet) battery holder which is perfect for my needs but I have not been able to find it for sale, I believe this flashlight still uses two fixed 4X series-parallel 21700 cell holders which would work, but I cannot yet get NealsGadgets to even ship those to me at my APO, AE address:

 

[Laser_Project]

I am not happy LG shows this cell is not good for 15 amps continuous discharge, closer to half that, even less, depending upon the temperature. I found a site listing this as a INR21700 M50 10 amp CD cell, and NITECORE listing it as a 15 amp CD cell on their NL2150HPR wrapper, both well over the manufacturer specifications. I thought better of NITECORE specs.

LG Specifications