Question about battery charging and safety

[xXToYeDXx]

Hello.

I'm a new mech/RDA user. My first build is a .6 Ohm single micro coil, 24 gauge kanthal (5/6 wraps) vertical on a Kryptonite 454 Big Block. Reviews on this dripper were excellent but they worried me a bit when they talked about how inconvenient it could be to build on this deck. It is weird, but I haven't had much trouble. I'm using a Stingray X Black Copper limited edition. Both of these devices are authentic, as in not clones. I figured if I'm going to get into dripping and building I might as well spend the cash on quality devices so I can focus on juices from now on.

My question is, and I have asked this elsewhere with no clear answer, is it safe to use the batteries below 3.7 volts to get more life out of them? If not, what makes it unsafe and what are the dangers of dischargin beyong 3.7 volts? For now the batteries are still hitting hard enough for me at 3.7 but I'm not sure if it's safe to keep vaping on it longer than that. Can I take it to 3.5 or 3.4, maybe 3.2 before charging it?

I'm have 2 Sony 18650VTC4 2100 mAh 30A that I switch between. One on the charger while one is in use.

 

[State O' Flux]

Hello.


My question is, is it safe to use the batteries below 3.7 volts to get more life out of them? Can I take it to 3.5 or 3.4, maybe 3.2 before charging it?

The absolute lowest, and relatively common standardized, safe discharge voltage is 2.5v... but you'll find that your vape performance is gone long before that. With experience, you'll discover what your satisfaction lower limit is.
Although I don't check anymore, mine tends to hover around 3.4v before I'm ready for a fresh battery.

 

[xXToYeDXx]

The absolute lowest, and relatively common standardized, safe discharge voltage is 2.5v... but you'll find that your vape performance is gone long before that. With experience, you'll discover what your satisfaction lower limit is.
Although I don't check anymore, mine tends to hover around 3.4v before I'm ready for a fresh battery.

Thank you. I can't even begin to tell you how hard it's been to get a straight answer. I know the point where it "feels weak" is subjective but there has to be a safe lower limit that will get me more vape time per cycle without risking damage to my battery. Seems 2.5 volts under load is the absolute lowest, but you're right. I might find it too weak at around 3.4 or 3.3. So thank you.

 

[State O' Flux]

Thank you. I can't even begin to tell you how hard it's been to get a straight answer. I know the point where it "feels weak" is subjective but there has to be a safe lower limit that will get me more vape time per cycle without risking damage to my battery. Seems 2.5 volts under load is the absolute lowest, but you're right. I might find it too weak at around 3.4 or 3.3. So thank you.

No problem. Repeated deep discharges aren't very good for battery life... so if I were to say - "try not to go below 'X'" - 'X' would be 3.2v.
You'll get used to what is acceptable for your subjective needs, with your builds and attys... and then you'll take a draw on a juiced RDA and think "this ain't gettin' it"... pop the battery and discover what your personal low V is.
You'll find, if you're paying attention, that it's a fairly consistent value... and like me, you'll just trust your tastes to know when it's time for a fresh batt.

 

[Jackson]

The absolute lowest, and relatively common standardized, safe discharge voltage is 2.5v...

That's not exactly true, MOLI and LG both have high drains that figure their mAh based on a 2V cutoff.

Here's a little tidbit from Battery University, a rather respected source.

Do not boost lithium-based batteries back to life that have dwelled below 1.5V/cell for a week or longer.

The batteries from the top manufacturers, Samsung, LG. MOLI (inventor of the IMR), Panasonic and Sanyo are quite durable (and cheap) these days, and all have excellent safety records.