Life span of Samsung 25r and LGHE2

[Mrez]

Another day and yet another question. I picked up a pair of the above batteries last year around october or november. They've been rotated daily and charged after use. I've probably used them down to about 3.7 volts before charging them. Mech use only, and in the .25 range to .5 range, but mostly in the upper levels of that range. I haven't noticed to much of a decrease in performance on either one, or in battery life for that matter, and i would say since april they have not been used nearly as much due to the use of an eleaf while driving (where I do a good chunk of my vaping).

So I'm pretty sure I need new cells soon (actually just got a pair of 25rs and vtc5s..but only the 25rs are for mech use), but my question is how soon? Am I still in the safe zone with these batteries after such long use? I know they degrade over time, but i am not certain as to how much from a practical stand point.

 

[Mooch]

You should get a couple hundred cycles, at least, with those cells before you really start to notice a loss in capacity. As long as they aren't ever overcharged or left fully discharged or charged for a long time. They're still perfectly safe to use now.

As the cells age more you'll start to notice that you'll need to charge them sooner and sooner as their capacity drops. This isn't a safety issue unless you start lowering your build resistances. The internal resistance of a cell goes up as it ages. This can be a problem if the cell is being used at or near its current rating because of the additional heat created by this rising internal resistance.

At a certain point you'll become frustrated with how often you have to charge them. You might even notice that they feel hotter when you take them out for charging. Either of these scenarios means it's time to buy new cells.

For now though. I think you're OK with those cells.

 

[Mrez]

Thanks Mooch thats great. I was thinking about bringing them on vacation with me along with the new cells, but wasn't sure. I never overcharge them (and I have an xtar charger), and when testing them they routinely come out to 4.19, and they always get charged when down to about 3.7 or so and rested untill they come up in rotation again. So thats a bit of relief...vape budget blown for a month or two. XD

 

[sonicbomb]

Those cells should be good for about 300 discharge cycles. A discharge cycle can be partial ie. charged twice when 50% discharged equals one full discharge cycle. As the battery ages the CDR will drop, So build a good safety margin into the amp limits for your builds. Only charging to 4.1 volts and never discharging below 3.6 volts will also help longevity. It's also a good idea to let them rest for an hour after charging.
I date my batteries which helps to identify which ones may be reaching the end of their useful life.

Remember batteries are cheap, burns are painful.