Panasonic NCR18650B Protected and Unprotected

Hello all. I recently purchased a Convoy S2+ 7135x6 flashlight as well as the Lii 202 charger I was recommended and now I am looking at the popular Panasonic NCR18650B batteries online. Would you recommend the protected versions or the standard unprotected ones on Illumn?
Protected: http://www.mtnelectronics.com/index.php?route=product/product&path=59_88&product_id=55&sort=pd.name&order=ASC
Unprotected:https://www.illumn.com/batteries-chargers-and-powerpax-carriers/batteries/18650-panasonic-3400mah-ncr18650b-flat-top.html
Thanks for reading! :smiley:

I used to push protected cells (“what can it hurt?”), but now I only get unprotected.

Most doodads worth anything will have their own built-in protection and not let you drain the cells too far before cutting off.

Protection circuits have parasitic drain — small, but there — that will eventually drain your cells just sitting around doing nothing, especially if you already drained them in a light without recharging them.

Most chargers probably won’t overcharge your cells, and this is maybe the only extra bit of protection where protection circuits might be better as a “just in case” level of defense.

Protection circuits will kill off high drain rates, so for whether high-drain lights, vaping equipment, etc., no protection is the norm.

The sense-strip on protected cells means the cell has to be double-wrapped, even if only a strip of kapton tape, so it will be thicker and possibly not fit into a light whose tube is marginal. Also, protected cells will be longer, and also possibly not fit.

Protected cells usually have button-tops, and some lights just won’t take flat-top cells, period, so you’d need to install your own button-tops, use a solder-blob, or use (gaaah!) small magnets.

So, all things in balance, I get unprotected cells, period.

Well the choice seems obvious now. Thanks for your replies.

+1

I prefer protected one.
But my Convoy S2+, Eagle Eye X2R,X5R and Skilhunt H03 has short tubes and protected cells do not fit. No problem with Zanflare F1.

The S2+ with 3/5 mode UI does not have low voltage protection (only warning). However if you get into the habit of mechanically locking out the light after use then there should be minimal risk with unprotected batteries.

Larger protected batteries struggle to fit in some S2, though this is more of an issue for protected GAs. Most newer protected cells (usually protected GAs have minimal performance difference compared to unprotected, however this wouldn’t be the case of older protected Bs. The S2 you have only pulls 2.1A anyway, so you should be fine with unprotected or protected Bs.

Personally I would recommend unprotected GAs (or even 30Q/VTC6) if you plan to use more powerful lights in the future.

Yea!

Protection circuits just get in the way once you understand the basics of li-ion cell care. The standard low side MOSFET ones (at the rear) pose an additional risk for those in the maladroit league: a rip on the wrap under the logic circuit feeding strip means short circuit condition sooner or later. Nasty stuff that will end up smelling real bad (literally).

A thing which sort of busts my balls is when a gizmo requires button tops. The only reason I see for that is for the device manufacturer to avoid having to deal with reverse polarity protection (piss poor, imho). In these cases maybe I should put a good blob over the cell cathode just to see what happens when inserted in reverse.

Cheers ^:)

@M64S2, welcome to BLF :laughing:

I recommend starting with protected cells and when you are used with the handling, been around for a while and know the pros and cons for yourself, you can always get something else.
Li-ion cells have risks because of the instable chemistry. The protection circuit gives an additional layer to protect from 3 dangerous incidents: overcharging, overdischarging and shortage - all of them can lead to venting and/or explosion.

Suggestion: Read the Li-ion safety 101. If most of what’s written there is new to you, start with protected cells. :wink:
These still need to be handled carefully, but are inherently safer.

With your setup the protected NCR18650B is great, as it has a lot of capacity for the prize, and the cell fits into the S2+ and the Lii-202 regardless of the increased size. With a 6x7135 linear driver (~2100mA) the protection does not hurt output, so you don’t lose brightness.

Have fun

I use protected cells in my H03 ( fenix 18650’s)