LI-ion cells - ignoramus question

[saypat]

Hello. I’m embarrassed to ask because I have been around of many years I have had (2) cells go bad lately. These were in lights that have a side switch. Is there a drain in these types of lights? When does a cell go bad, at what voltage? And can they be brought back to life? My latest was a 14500 WindyFire, it read .98 on the meter. I just checked again and it is now up to 2.5V. Maybe it will still be ok?

With some 70+ lights lying around, it’s hard to monitor them all. Guess I need to do a tailcap lockout on the side switch lights? Please correct me if my assumptions are wrong.

thanks for the help!

[The_Miller]

It is my understanding sideswitches kind of “wait for press” and are using a little bit of power doing so
I keep them locked out (or prefer a second tail switch for the lockout)

[HKJ]

It do not have anything directly to do with side or tail switch, it has with electronic or mechanical switch.
But a side switch is much easier to make electronic than a tail switch!

One way to spot an electronic switch is that it is a push button only, it do not lock in on position.

[saypat]

@HKJ

It do not have anything directly to do with side or tail switch, it has with electronic or mechanical switch.
But a side switch is much easier to make electronic than a tail switch!

One way to spot an electronic switch is that it is a push button only, it do not lock in on position.

thank you. Is it an electronic switch if one has to hold the switch down to turn off the light?

[khas]

Yes that would be an electronic switch

[mattlward]

Yes, that would be an electronic switch. Some lights have almost no drain and some tend to draw a little more. I know, very general statement… But, do watch the batteries every few months.

[HKJ]

@saypat

thank you. Is it an electronic switch if one has to hold the switch down to turn off the light?

That sound like an electronic switch.

I have flashlights with electronic switches that can last many years on a battery, but I do also have some that will drain a battery in a month.

[saypat]

@HKJ

@saypat

thank you. Is it an electronic switch if one has to hold the switch down to turn off the light?

That sound like an electronic switch.

I have flashlights with electronic switches that can last many years on a battery, but I do also have some that will drain a battery in a month.

THIS amazes me!

[HKJ]

@saypat

THIS amazes me!

One of the bad and one of the good:

[Halo]

@saypat

These were in lights that have a side switch. Is there a drain in these types of lights?

We call it “parasitic drain” and as others have said it varies from almost nothing to horribly high. Anything with high drain is a pure piece of junk, worthless imho. Ensuring the drain is low is a requirement for making even a half-way decent side switch light.

[saypat]

@Halo…

@saypat

These were in lights that have a side switch. Is there a drain in these types of lights?

We call it “parasitic drain” and as others have said it varies from almost nothing to horribly high. Anything with high drain is a pure piece of junk, worthless imho. Ensuring the drain is low is a requirement for making even a half-way decent side switch light.

I found out the following about my Manker T01 which has an electronic switch:

Yes it does but the current draw is so miniscule as to not be a concern; it’s 6 microamps which should last about 48 yrs on standby with an Eneloop XX (leaving the cell’s own self-discahrge out of the calculation) or 4yrs with a typical 14500 cell @ 600mAh capacity (again leaving the cell’s self-discharge out of the calculation).

48 years! I’ll be long gone, I’ll have to add an addendum to my will.