Decided to Go Unprotected

[DonK]

Well, after casually researching this subject for weeks, I decided to run with Panasonic 18650 3100 UNPROTECTED cells.

Seems to me that with the latest battery and charger inovations we just don't need the protection circuits any longer.

In the good ol' days battery chargers were not so smart, so protection on the cell was an essential. Now - with the advent of the Panasonic 3100 - we have cells with additional safety features and much lower min voltage levels (2.5v in this case). Also, most battery chargers are now smart enough and have reverse polarity protection, thermal protection, voltage cutoff etc all built in.

So, my conclusion was why pay extra (granted, not much) to have something that is longer and more fragile - the safety features are mostly redundant.

So, I ordered the unproteced Panasonic 3100 cells to be used with my Tenergy smart charger.

Did I make the wrong decision ? Only time will tell if I made the wrong move - unless you tell me first :D

Disclaimer
I am far from expert in this stuff, just someone who researched a lot and drew some conclusions based upon current reported technology.

 

[sidecross]

Re: Decided to Go Unotected

As long as your lights are using just one 18650 at a time, I think the only risk is not obtaining the maximum battery life.

 

[ChrisGarrett]

Re: Decided to Go Unotected

Welcome to the dark side.

'You can enter, but you can never leave.'

Just be mindful, buy quality stuff, run them in single cell lights and you'll be fine.

I mean, if prices were the same, I'd take protected batteries, but they're not.

Chris

 

[Norm]

Re: Decided to Go Unotected

Be careful not to inadvertently short your unprotected cells.

Norm

 

[mvyrmnd]

Re: Decided to Go Unotected

The charger is only half the equation. As long as the light you're using them in has a reliable low-voltage cutoff, then you'll be fine. If not, you risk overdischarging the cell.

 

[DonK]

Re: Decided to Go Unotected

Thanks. Not sure about the light circuitry (Fenix, Sunwayman, Olight) but they are certainly just single cell lights. I purchased the latest Panasonic 3100 cells, so should be OK as far as quality goes.

I did not mind the additional couple of $ for the protection, I just figured it was added complexity and fragility that I could live without. I have some nice plastic bozes that hold 2 18650s securely, so hopefully, shorting will not be an issue.

The guys in the protection business could be out of business soon if lights, chargers, and cells continue to develop - as thy should.

 

[lwknight]

Re: Decided to Go Unotected

I use unprotected cells in my single cell lights. They all cut out at around 3.2 volts or higher.
Definitely there is benefit in protection when running 2 cells because the light will not
cut out at the general 3.0-3.2 volts since 2 dead cells will still have 5 volts.

Lights made for 2 cells only could be made to protect batteries but we like versatility
so that's a mute point.

 

[DonK]

Re: Decided to Go Unotected

Thanks

If I ever get a 2 x 18650 light I will be sure to get one that shuts down at 5v, or use protected cells.

My short term goal is to change out this keyboard - it seems to be a little eratic and will get me into trouble sometime soon :oops:

 

[Overclocker]

Re: Decided to Go Unotected

many single cell lights will overdischarge if left on overnight

the exception are lights with built in overdischarge protection like zebralights and maelstrom x10

you really wanna risk that? in exchange for what? a 2mm shorter cell? less complexity? what's so complex about a protection circuit anyway?

 

[mossyoak]

Re: Decided to Go Unotected

Welcome to the dark side.

'You can enter, but you can never leave.'

Just be mindful, buy quality stuff, run them in single cell lights and you'll be fine.

I mean, if prices were the same, I'd take protected batteries, but they're not.

Chris

Totally agree, I mean there is no way keeping my fingers intact is worth the extra $5 per cell. I need that money to buy more flashlights.

 

[Shadowww]

Re: Decided to Go Unotected

Totally agree, I mean there is no way keeping my fingers intact is worth the extra $5 per cell. I need that money to buy more flashlights.

Fun fact: there have been 0 reported incidents of high-quality (with high-quality I don't mean UltraFire crap) unprotected batteries exploding in single-cell lights.
Also, another fun fact: protected battery is more likely to short-circuit itself due to protection circuit fault, or due to mechanical damage (e.g. drop) - it's positive and negative contacts are separated by 0.2mm thick tape.

 

[Norm]

Re: Decided to Go Unotected

Totally agree, I mean there is no way keeping my fingers intact is worth the extra $5 per cell. I need that money to buy more flashlights.

:lolsign:

 

[Admiralgrey]

Re: Decided to Go Unotected

When used in an unregulated incan my cells rarely break 3.80v before they get swapped out. Loosing overdrive is pretty noticeable, but that said, while discharging cells bellow 3v wouldn't happen in my hands in such a setup, there are such things as loaner lights for a reason. If said torch gets turned on in a bag unnoticed, I would be worried about starting a fire before the cells got to exploding.

I've been salvaging 18650s from laptop packs and as a result have a oodles of aging unprotected cells. Its allowed me to delve much deeper into this hobby than my shoestring budget would have allowed, but at the cost of constant vigilance. Luckily this forum contains all of the information you need to be safe.

That all said, I'd still like to reserve the right to change my opinion should I find myself holding a blow torch where my ROP used to be.

 

[The_Driver]

Re: Decided to Go Unotected

I think, no matter what, if it's possbile to have a protection cirsuit, one should use cells that have them. When you pay attention to what your doing nothing will happen, but after a while you will get lazy or forget something etc. What happens then??

 

[roadkill1109]

Re: Decided to Go Unotected

I've been using these Panasonics (both the 2900mAh and the 3100mAh) for several years now, i use them for almost anything that will take an 18650, so far no problems whatsoever. Still able to keep their charge and provide good long runtime. But you have to be careful in using them in series, some lights will cut off at 3volts, but when that happens, that means one of the two 18650 cells is already zero or close to zero. You can ruin the battery this way. Just thought to inform you so you are aware. (I've killed some unprotected cells in my time)

 

[hellokitty[hk]]

Re: Decided to Go Unotected

many single cell lights will overdischarge if left on overnight

the exception are lights with built in overdischarge protection like zebralights and maelstrom x10

you really wanna risk that? in exchange for what? a 2mm shorter cell? less complexity? what's so complex about a protection circuit anyway?

But with a solid quality cell overdischarge is very unlikely to cause an explosion. It will only damage the cell and set you up for an explosion when you're charging. So in fact it's not extremely dangerous if you accidentally leave an unprotected light on all night as long as you check before you charge.

 

[ChrisGarrett]

Re: Decided to Go Unotected

Totally agree, I mean there is no way keeping my fingers intact is worth the extra $5 per cell. I need that money to buy more flashlights.

Well, if you're that worried, stick to alkalines.

I reload my own ammo and shoot guns, if I took your path, I'd do/have neither.

I mean, there's always a chance that the ISS deorbits and crashes into my house, right?

I can't speak for you, but I'm smarter that that.

Chris

 

[mossyoak]

Re: Decided to Go Unotected

Well, if you're that worried, stick to alkalines.

I reload my own ammo and shoot guns, if I took your path, I'd do/have neither.

I mean, there's always a chance that the ISS deorbits and crashes into my house, right?

I can't speak for you, but I'm smarter that that.

Chris

Cute response, alkalines are even worse.
Actually I reload for my .338 Lapua, partially because its $5 a bang otherwise and I enjoy doing stuff myself.
The problem with unprotected rechargable l-ions is you dont have any warning, where as with reloading you know what you put in there and the science behind it tells you the results.

 

[DonK]

I note that most newer lights have a cutoff and/or a low power warning light. Going forward we should be OK

 

[fivemega]

Fight is for $5 extra ???
You already made your decission and purchase the unprotected cell and they are available in the market for guys like you.
Even if there is no serious danger for unprotected cell, but still possible accidently and safely to overdischarge and damage the cell. Then you must pay more than $5 to purchase another cell.
Isn't it smart to ensure your cell and buying insurance (protection circuit) for peace of mind?
About 12 years ago I bought numbers of unprotected Li-Cobalt cells. One after another went to trash because of overdischarging. Few years later, protected cells came to market and I bought 40~50 protected li-ions and some of them still in working condition. I also have some unprotected IMRs which are not possible or available with protection circuit.