18650 battery question

[rnln]

I have 3 pair of batteries: Efest 2000 mah, CGR18650CH 2200 mah, and NCR18650B 3400 mah. I bought them one by one but proximately at the same month. Now the efest usedot last 3, 4 hours but only last around an hour or two now. I think it's going to go soon?
For the lasting, I like the NCR18650B because it last the longest, but people are saying it is not safe. Is there are better one out now? I have not searched for months.
Thanks

Note: I am using mod: Vamo and itaste SVD

 

[dr g]

That is typical, efests have shorter longevity despite good initial specifications. In my experience, they just run down faster. The NCR18650B is safe for both of those mods, especially in VW mode.

 

[Thunderball]

Go ahead and get you some AW's or some Panasonics. They will last so much longer. I went down that same road myself.

 

[Thrasher]

get the 2900mah panasonic PD. a good battery that lasts pretty long as well.


the reason not to use the b in a regulated mod is because it is not a high drain battery, it has a 6.8 amp limit. I use them in my mech where what you pull out is what the battery gives.

in a regulated mod say you have the voltage set to 4 volts pulling roughly 3 amps. as the battery dies it needs to pull MORE amps out of the battery then turn that extra power into voltage to stay at 4 volts. in some extreme cases this can easily reach 8-9 amps.

two things happen when using a low drain battery. either the vape seems off because it doesnt have all the power it needs or the battery is being driven too hard to keep up. which may lead to stress and failure.


many of the better batteries have the standard drain limit and a higher short peak. and even though a battery may handle the load using the short peak time, it is not wise to constantly strain a battery beyond the approved constant load amperage.

 

[BardicDruid]

It's not a good idea to use a NCR18650B in a VV or VW mod because it has only a 6.8A max discharge rate. The CGR18650CH is a better bet since it has a 10A discharge rate, the one I would suggest is the Panasonic NCR18650PD, it's 2900mAh and is 10A discharge rate.

 

[tc1]

The NCR19650B is rated at 6.8 amps ... it will work just fine in a Vamo or SVD.

As far as the Efest, that definitely sounds like it's not holding a charge. How long have you been using it? If you've rode the hell out of the battery then I can see it lowering its' charge like that. If you haven't used it all that much ... might want to make sure your charging is working properly.

 

[dr g]

in a regulated mod say you have the voltage set to 4 volts pulling roughly 3 amps. as the battery dies it needs to pull MORE amps out of the battery then turn that extra power into voltage to stay at 4 volts. in some extreme cases this can easily reach 8-9 amps.

This really can't happen with common regulated mods up to and including DNA20D mods. Run the numbers.

 

[Thrasher]

This really can't happen with common regulated mods up to and including DNA20D mods. Run the numbers.

someone already did it for me

http://www.e-cigarette-forum.com/forum/provape/334831-technical-why-high-drain-batteries.html
with the provari being rated at 90% or higher efficiency it can pulse to 9 amps. so with the less efficient chinese converters what are you really pulling?

the dna/kick is DC to DC converter so a very different theory needs to be applied and cannot be included with PWM devices.

 

[dr g]

someone already did it for me

http://www.e-cigarette-forum.com/forum/provape/334831-technical-why-high-drain-batteries.html

Look at the amperage numbers in that example.

Edit: The "pulse" amperage is BS, the whole point of PWM is to provide smooth equivalent power, and it's not the same as "pulse" battery rating anyway. The battery will never see an 8+ amp load for even 1 second.

 

[tc1]

Most chinese mods won't output more than 11 watts on a single 18650 ... 6.5 amps is plenty.
They also have builtin battery protection which will limit the draw amps on a battery.

I use to run 5amp ICRs on a Vamo and the batteries never even heated up.

 

[Baditude]

 

[dr g]

someone already did it for me

http://www.e-cigarette-forum.com/forum/provape/334831-technical-why-high-drain-batteries.html
with the provari being rated at 90% or higher efficiency it can pulse to 9 amps. so with the less efficient chinese converters what are you really pulling?

the dna/kick is DC to DC converter so a very different theory needs to be applied and cannot be included with PWM devices.

Please stop putting out misinformation.

 

[Baditude]

Please stop putting out misinformation.

Instead of merely accusing people of putting out misinformation, how about providing links or references to back up your information some time?

Anyone can say something is incorrect, but few provide the documentation to support their case. I trust Thrasher to share only accurate information over yourself anytime. And if he ever would make a mistake, I know he's big enough to admit he was wrong.

 

[dr g]

Instead of accusing people of putting out misinformation, how about providing links to back up your information some time?

Anyone can say something is incorrect, but few provide the documentation to support their case. I would trust Thrasher to only share accurate information over yourself anytime.

When someone is this far out to lunch, there is no "documentation" to support the case against it. I mean he's claiming Provaris, etc. aren't DC/DC converters when his own link ought to clear him up on that.

 

[Baditude]

When someone is this far out to lunch, there is no "documentation" to support the case against it. I mean he's claiming Provaris, etc. aren't DC/DC converters when his own link ought to clear him up on that.

So are you saying that Provape doesn't understand PWM or what? You still haven't provided facts to back up your own case, only accusing someone of putting out inaccurate information as you typically do.

 

[dr g]

So are you saying that Provape doesn't understand PWM?

I wouldn't be surprised if that specific part of the writeup was done to justify the AW battery recommendation.

 

[Baditude]

I wouldn't be surprised if that specific part of the writeup was done to justify the AW battery recommendation.

Yeah, ok... That response would be my expectation coming from you. Again, just a generalized statement thrown back without any specific explanation to back up your statement. This gets to be monotomous. This conversation will lead nowhere, so I'll bow out at this point.

 

[Rader2146]

A little [very] technical reading on the topic.

Understanding Boost Power Stages in Switchmode Power Supplies

The people at ProVape are correct...Our batteries can be subject to VERY high amp loads due to current pulses of a boost converter. How much current depends on too many variables to even speculate, but it certainly can be as much as double the average current.

BUT......I take it with a grain of salt. Here's why...

A battery's max discharge rating is set with the goal of limiting heat production. Batteries have internal resistance, and when you have resistance and electrical current, you get heat. Battery gets to hot...bad things happen. So say you have a battery rated for 6A, and you are pulling 4A average current from the battery. This means that you could have 8A peak current being pulled from the battery. This peak, however, is only ~100 microseconds in duration (0.0001 seconds) and repeats itself 800 times per second.

Is that enough time to generate enough heat to damage the battery? I would argue that it is not. My reasoning behind that argument is the [probably] thousands of Provari Mini's that have bee sold that do exactly as I described above. The AW 18350 is rated for 6A continuous discharge and by ProVape's own proclamation for high drain batteries, their device is pulling 9+ amps from a 6A battery.

That doesnt mean that I would recommend using an ICR battery in a VV/VW APV though...ICR is just too volatile to push your luck.


One last thing...if it is powered by a battery, and allows you to change the voltage either up or down...it is a DC-DC Converter

 

[ZW99GT]

I've been reading quite a bit about the ncr18650 A & B's and how they aren't suitable for vaping. They certainly aren't super high drain but I've had two A's in rotation for over one year in a Vamo (around 1 battery a day) and they have been excellent. Never had an issue or one even get warm in over 150 cycles. Theory of what you've read on a blog do have a place in this game, but id be careful saying they aren't completely unable to perform in a regulated mod without personal technical experience of why not. They been one of the most popular cells in recent years in a few different hobbies I follow, with 0 documented issues to my knowledge. Would love to see a case of them struggling to keep up with reasonable amps or any extreme failures you've seen.

 

[rnln]

Thanks all for suggestion. I am back to square 1.
Do not use 18650B because it's not protected (the longest last I like).
18659CH is ok but not the best, because it's low discharge rate (and doesn't last long, to me). I vape constantly 100% of the time.
ZW99GT suggested not to use NCR (include the NCR18650PD?)
Now, what best to use?

Another concern, the 18650CH and 18650B is 3.7v, while the 18650PD is 3.6v. Does it matter?
Thanks.