Cr123a? 2.5? 2.2?
I have some that are 2.9 and they still work. How far down do they need to be before they need to be thrown away?
Same with Lithium AA and AAA.
Is there a chart somewhere that has usefulness/safety/longevity of all primary batteries?
When they no longer properly power the device they are in ? Maybe ? Pretty sure primaries pose zero danger when the voltage drops. Mind you, rechargeables shouldn’t either. Can’t really damage primaries due to low voltage. Its not like there is a charging cycle to damage either.
Run ’em ’till they’re dead, Fred. I milk them for the last drop of life they have in them.
I just make sure to never match up pairs of unequal charge. If a set is showing signs of running down, I set them aside in a separate box to be run to death in a single battery application. Mind you, I also bend over and pick up pennies so others might do things differently.
Rechargeables, of course, are another matter entirely.
I discard them when they don’t do the job at hand well enough; don’t produce sufficient light or won’t operate the game camera for the length of the video clips I want, for example. AFAIK, there is no inherent danger to running a primary lithium to a low state of charge.
If anyone can tell me the point of repeating a response pretty much word-for-word, please inform me.
I’m itching to know.
Me also 
Thanks for the info (redundant though it might be) .
I have a solar-force L2p running a Customlites P60 UV365 drop-in that can only take primaries.
I don’t want to ruin anything in that setup so I will match up pairs voltage-wise. I have had alkys ruin flashlights before and I don’t want to screw up a more expensive light.
IBID
This always makes me wonder why people buy lights that only run on CR123 batteries. Why not buy a light that takes rechargeable RCR123 cells?
The usual answer is that primaries have greater capacity, so they can run the light longer.
However, this assumes you use fresh primaries all the time (i.e., you’re rich or you’re a government worker such as LE that gets free batteries). For the common shmuck, he’s going to run the primaries until they’re empty, then change them. This mean, on average, that your cells have only 50% of their capacity.
Rechargeables you can top-up and keep full in your light all the time. So, the real comparison of capacity is a full RCR123 vs a 50% depleted CR123. This puts the usable capacities much closer, and with no risk of not knowing how much capacity is left in your batteries if you use rechargeables.
IMO, the clear winner is rechargeables, unless you’re rich enough that you can afford to always use fresh primaries.
If you absolutely need a long run time for a certain outing, then you can put in fresh primaries. But for most uses, what’s wrong with rechargeables?
This seems pretty simple, sharing experiences. Validating and adding to the n=1
BLF would become a less nice place if we are expected to refrain from reactions if somebody else had posted something similar. 1x thanks in a GAW, 1x nice job or awesome in a cool mod, 1x nice review, like the pics under a good review, thanks for making this GB or special light possible just once to a team that worked hard.
Besides there is a good chance somebody is typing the same as you but is checking a source at the same time or just walks away for a couple of minutes and then post.
Smile when you are repeated, seems better for your heart and will surely cost far less energy then posting a not nice reaction to it says me, Dr Miller (smiley meaning no hate or negativity meant, BLF is a friendly place and as such this post is written and hopefully received.)
I Concur
I think you read far too deep in to my post !
Fully agree with what you are saying. I’m just baffled as to why, a few posts later, someone copies word for word ( almost ) a previous post, instead of a simple +1 or I agree. But hey, its just me I guess.
I also do not classify my response as “not nice”.
It was a simple non aggressive question.
{quote}peabody… How far down do they need to be before they need to be thrown away?{/quote}
Surely you meant to say “recycled’ and not ”thrown away”. Batteries in the ground water are a no-no.
HereAgainAgain, I must hav read it too negative then
And here you go:
+1
I live in rural America and there is no recycling center close to where I live. I will search out a place that will take my (throw-a-ways) to appease all the +1’s and not start “Internet Word War III” O:-)
All of my other lights use rechargeable batteries and I agree with you. The deal with that particular drop-in is it has three levels of output and it can only take the output voltage of two cr123’s ( at least that is what the P60 builder tells me). They do have a long shelf life and are cheap enough and I use the UV light only on rare occasions.
With Alkies I use them in higher drain things first then when they no longer power that item I put them aside for things like computer mice, wall clocks, etc.
I have not bought a battery for light duty stuff for years 
Cheers David
Last time I was in a Lowe’s I noticed that they had recycling collection boxes for batteries and CFL bulbs.
You’re playing Russian Roulette. 1 chamber loaded when the alkaleaks are full. 5 chambers loaded when they’re depleted.
Putting a fully charged Alkie in a low drain device is risking leaks a lot more than putting a half charged one in as its total lifetime is shorter, say 1 month in high drain and 6 month in a low drain against 12 month in a low drain only.
The only leaks I have had is in things I tend to forget about, kids toys that are no longer played with etc.
Cheers David