When to recharge batteries?

[Snowdragon]

Indeed Blue that is exactly what I meant with my comments concerning of deep cycling vs shortened longevity vs cost. To discuss this properly one has to take into account a few variables like rate of discharge, state of charge, and battery chemistry. E-cig manufacturers are known to be a little vague and misleading with their claims. Ever heard that a 1 ml Cartomizer is equal to 1 pack of cigarettes? How many of you believe that statement? Do you believe every battery will really get exactly 300 cycles, no more, no less?

If you wanted to get the absolute greatest amount of cycles from your Li-on battery then you should do the following. Only use them while you are standing in a 34F degree meat locker and never remove them from the meat locker. If fully charged voltage is 4.2v, recalibrate your charger to only charge up to 4.1v then check the battery and recharge it at 3.8v.

Of course, going to such extremes for battery longevity is a bit overkill. In the world of Li-on batteries what is this mystery number that is considered fully discharged? Is it 0? Well the accepted fully discharged voltage is 3.0v for a 3.7v battery. A fully charged battery is considered 4.2v, but we know from Professor Morandir (or is Dr.?) that the fully charged number can vary from device to device but hovers around 4.16v - 4.2v.

If you have ever read any back and forth between the Professor and I discussing battery voltage testing results we note how many minutes it takes to get from 4.2-4.1Xv to around 3.85v before drop off or battery fade occurs. If there is sweet spot in vaping juices, this voltage range is the sweet spot for 3.7v unregulated Li-on batteries for vaping.

Ideally you want to avoid deep-cycling, but how does that translate into numbers? The State of Charge is 0% when fully discharged or in this case an accepted 3.0v and 100% fully charged is 4.2v., we have a range of 1.2v. Testing shows us that to attain maximum battery longevity it is best to not drain the battery past 40% of the 1.2v State of Charge or 3.72v. From the good Professor's testing we know that blinky blinky time occurs around 3.65v +/-.

Experienced Vapers usually can detect battery fade as flavor and vapor start to fall off especially when using a standard 1 ml single coil cartomizer. However battery fade can be very hard to detect for new Vapers, when using strong flavors, or using a dual coil set-up with a battery that has quick drop-off. A quick drop-off being that time from 3.8v down to 3.65v blinky blinky time.

Now most Vapers usually have multiple batteries and use them in rotation with an average 1 charge every 1-2 days. At 300 charges we are looking at 10 months to 15 months of use. Of course we all know that may vary but it's my experience not by much.

When folks chime in and say, "I have only had my battery for 2-3 months and it's dead, what's the deal?". The first question to ask is, "How many batteries do you use and do you always use the battery until it blinks?" If they only have 1 battery and charge it 3 times a day, using it until it blinks each time, that battery has a shortened lifespan and is simply all used up.

There are other factors that can have a dramatic affect on battery longevity like temperature exposure. Person A lives in a cool climate and always vapes until blinky blinky time. Person B lives in a very hot climate (Death Valley) and works outdoors all day long. They keep their batteries in their pocket or in their hot truck throughout the day, but stop using their batteries the second the detect battery fade never waiting for blinky blinky time.

Who's battery will have longer lifespan? Person A will have a longer lasting battery due to the affects of temperature exposure and the slower rate of battery discharge despite their deep cycling tendencies.

Personally I try not to wait for blinky blinky time, but it happens and I really don't give it much thought. If I can get 230 cycles or a year"s worth of use out of my $15-$20.00 battery I can live with that. Especially since $15-$20.00 worth of analogs would last me about 3 days. The 3 worst things you can do to a Li-on battery is to deep cycle, over charge, or expose it to high temperature. So you would never want to advise any Li-on Battery user to deep cycle their batteries, deep cycling is primarily for older Ni-Cad batteries due to the different chemistry involved.

Is it some giant conspiracy that the battery manufacturers set the cut-offs around 3.65v to shorten battery lifespan? No. All things in the world of electronics have a variable factor. Take a 100 batteries and you will find fully charged ranges varying from 4.2v to 4.1Xv. The manufacturers simply took the low number like 4.15v, giving a State of Charge range of 1.15v, 40% of the State of Charge is .46v, which places a cut-off of 3.69v. Ideally a 4.2v battery would have a cut-off of 3.72v......anything less than that is technically deep cycling.

If you can avoid blinky blinky time, than do it. But if on occasion you can't (happens) it won't shorten the life of the battery instantly, although if you deep cycle every time it will indeed shorten the lifespan of your battery. The big question which only you can answer is.....is that shortened lifespan vs cost acceptable.

When I smoked I never smoked a ciggie all the way down to the filter. I generally put them out leaving about a 1/5 left, so that 1/5 or 20% was an acceptable loss factor for me.

Morandir has some cool test results from Blinky Blinky vs No Blinky Blinky...and total charge cycles.

[AudreySchroder]

Many discussions regarding product and product use is contradictory. There are different opinions on how things should be done regarding e-cigs. Some examples are steeping, battery charging, filling cartos and tanks, and juice storage. Some people are set in their ways, and others have just as strong as an opinion for the opposing method. Because there are a few different schools of thought, people get confused. The best thing to do is try a few different ways and see what works best for you.


For anyone who did not read the V4L - Weekly Newsletter sent 5/23, this is what it said:

"Lengthening Battery Life

Electronic cigarette batteries need to be cleaned so they function properly. To clean a battery, get a cotton swab, rubbing alcohol, and a sharp object -- sewing needle, safety pin, or thumbtack. First, remove the cartomizer or charger from the battery. Then, dampen the cotton swab in alcohol and swab the entire metal connection area. Next, take the sharp object and carefully slide it in and around all the small crevices (air holes, threading, and post) to remove built up residue. Be sure to go over every area thoroughly. Lastly, let the battery completely dry before using it. Cleaning your batteries once per week will help extend their life, as will using your battery until it is fully drained of charge. When you do charge it, make sure it is fully charged before removing it from the charger. Immediately after the battery is fully charged you should remove it from the charger. Check out our step-by-step video and visit our YouTube channel for more vaping tips and tricks!"

[Morandir835]

Excellent post Snow sir.

Just to add, most batt experts/manufacturers I've talked to say anything under 3.5v is considered deep cycling territory. A certain unmentionable item blinks at 3.4v saying the battery is low for that very reason, but doesn't shut it off. There isn't a pv (standard or mod) that shuts off before deep cycling. They do shut off when the batt reaches around 3.2v on any with any type of built in protection (which ever stick batt has currently on the market), but that's near the very deep end of the cycle....

[Morandir835]

Ms. Audrey that very last line is what started these discussions. Tests have been done (and not just by me, but the battery institute, manufacturers, etc.) that show deep cycling is bad for lithium based batts. Waiting until they blink to charge them shortens their life span, not increases it...

[LadyStrick9]

Ms. Audrey that very last line is what started these discussions. Tests have been done (and not just by me, but the battery institute, manufacturers, etc.) that show deep cycling is bad for lithium based batts. Waiting until they blink to charge them shortens their life span, not increases it...

(Thread added to Links Site 5/24/12 - Battery Section)

[TheBlueAdept]

Thank you Sir Snow for that well written and detailed response. As always, I appreciate the info I learn from you!!


Ms. Audrey,

I completely understand and agree that there are different schools of thought, preferences, and tastes when it comes to most aspects of vaping. The only topic at issue here is one that is based on proven scientific facts that have undergone testing and review from a very wide variety of sources, all of which are at odds with that one sentence.

I don't think it is any sort of big deal to most if not all of us here, other than being certain of what the true facts are so that those who do choose to take steps to prolong their battery life can do so with correct information. I'm not trying to add to any discourse that would be considered inflammatory, just trying to clearly point out what I perceive to be happening and hopefully help put it to rest.

[Morandir835]

On that note closing this thread everyone.