Battery life help!

[Thenewmrsk]

Hi everyone,

I have a question regarding batteries. I have a manhattan mod with a mutation x RDA. The coils usually run approx .67 ohms. The batteries I use are 18650 3.7v 2900mAh. I vape a lot, and am finding that I’m lucky if the batteries last a half hour. I have to carry around 4 batteries and my charger at all times. It doesn’t seem right. Am I using the wrong battery, or is this typical of the battery life? Any help would be greatly appreciated!

 

[itskohler]

This is not typical. How old are they? You may have gotten use to fresh batteries at 4.2V, and feel the performance at 3.7 isn't cutting it for you anymore.

 

[InTheShade]

Is that the Orbtronic battery?

I'd say it's not normal no. An 18650 on that build even with heavy vaping should last a few hours at least.

So a few questions.

Do you know what voltage the batteries read when you remove them from your mod?
What charger are you using?
What voltage are they when you remove them from the charger?
How many cycles do the batteries have - did you buy them new or used?

 

[Romano Cheese]

That sounds a little off. Unless your mod never leaves your lips for a half hour straight I don't think it should be draining that quickly. What batteries are you using?

 

[Baditude]

What batteries (specifically the brand and model) are you using? What charger are you using (specifically the brand and model number)?

Quality, Brand Name Batteries. Not all ICR and IMR cells are created equal. This is where the supplier/manufacturer comes into play. There are quite a few different makers, some you can trust, some you can’t. I will give a quick rundown of them and what makes them better. I recommend buying only the batteries from the link below, paying attention to model numbers and their specifications. (CDR is the continuous discharge rating in amps.)

Battery Basics for Mods: A Definitive Guide to Batteries for Vaping

Beginner's Guide to Lithium Batteries
​

I'm using a 0.6 ohm dual coil build on my mechanical mod. I'm a relatively heavy vaper, and a single 18650 battery lasts half of my waking day (two batteries a day). I'm using Sony VTC4 2100 mah 30 amp CDR batteries.

 

[edyle]

Hi everyone,

I have a question regarding batteries. I have a manhattan mod with a mutation x RDA. The coils usually run approx .67 ohms. The batteries I use are 18650 3.7v 2900mAh. I vape a lot, and am finding that I’m lucky if the batteries last a half hour. I have to carry around 4 batteries and my charger at all times. It doesn’t seem right. Am I using the wrong battery, or is this typical of the battery life? Any help would be greatly appreciated!

1: Are you using the wrong battery:
For you, sounds like it.

2: Is this typical of battery life:
I would say yes.

0.7 ohms, 3.7 volts
watts = 3.7 x 3.7 / 0.7 = about 20 watts.

2900mAh = approx. 3 amphours
3.7volts x 3 amphours = approx. 11 watthours

11 watthours/20 watts = half an hour !

Wow you're vaping like a chimney.


But anyway for your coil you should be using at least a 20 amp cdr battery, and I am not sure if there are any 2900mAh 20 amp cdr batteries.

 

[Thenewmrsk]

This is not typical. How old are they? You may have gotten use to fresh batteries at 4.2V, and feel the performance at 3.7 isn't cutting it for you anymore.

Ok thank you so much! Can you recommend a good / safe 4.2V battery?

 

[itskohler]

We don't have an batteries that we can use at 4.2V continuously without on-board electronics boosting the voltage. However, you are vaping at ~26 watts on a fully charged battery at .67 ohms. Bring your resistance down to .5 to be at 26 watts with a normal discharge of 3.7V, and you will get the same vape as you were at 4.2V at .67 ohms.

 

[Susan~S]

Ok thank you so much! Can you recommend a good / safe 4.2V battery?

Hello and welcome to the forum @Thenewmrsk. Glad to have you here!

You are going to want a safe-chemistry, high-drain battery with a high CDR. How high? I'll quote @tj99959 as this is the practice I follow with regards to amps & headroom.

When considering how low you can build you need to give yourself some headroom. I try to never exceed 50% of the CDR (continuous discharge rating) of a fully charged battery (4.2v). So with a 20A battery (like the Samsung 25r), that would be 10A. This Ohm's Law Calculator tells me that a 0.4Ω build is as low as I would want to use.

The reason that I place a 50% limit is because as a battery ages the mAh of the battery degrades, as the mAh degrades so does the batteries c rating (amp limit). So down the road, a 20A battery may only be a 10A battery."

With a 30A battery (like the Sony VTC4 or LG HB6), 0.28Ω is the lowest I would build.

======

I highly recommend you spend some time with @Baditude & @Mooch (two of our resident battery/safety experts) and visit their blogs. You are now 100% in control of your own safety (and others around you). Make sure you purchase an ohm reader and a voltmeter or DMM so you can measure your builds, check for shorts and measure the remaining charge on your batteries.

Here are links to some of Mooch's blogs:
* No matter what is printed on the battery wrapper: There are no 18650 batteries with a genuine rating over 30A!
* Links to all his battery tests to date: List of My Battery Tests | Mooch's Blog
* Picking a Safe Battery to Vape With: Table of 18650 Battery Safety Grades | Mooch's Blog

Baditude's Blog - Table of Contents: The blogs that address battery safety, Ohm's Law, CDR (continuous discharge rating/Amps) and how they all work together are detailed below:

BATTERIES

Battery Basics for Mods - The Ultimate Battery Guide
* Another essential read to understand which batteries are safe to use in mechanical and regulated mods. Includes a frequently updated list of recommended safe-chemistry, high-drain batteries with their specifications.

Purple Efest Batteries not as Advertised
* A cautionary blog that reveals that the purple Efest batteries may not have the specifications advertised. Also includes a commentary on "continuous discharge ratings" vs "pulse discharge ratings" of battery specs.

OHM'S LAW

Ohm's Law Explained for Vapers
* My attempt at explaining Ohm's Law in layman terms and how it relates to vaping.

Explain it to the Dumb Noob: Ohm's Law Calculations
* As simple as it is to use, some people have a tough time grasping the concept. Warning: Includes graphic photos of mod explosions.

BATTERIES - WHERE TO BUY

Only buy batteries from a reputable supplier (not ebay or Amazon) as there are many counterfeit batteries being sold. Here are several reputable battery suppliers in the US.

* RTD Vapor
* Illumination Supply
* Lighthound
* Orbtronics

 

[Hans Wermhat]

I use Sony VTC4's. They are the best mix of CDR and mAh in my pinion. They will handle a 30A load and have 2200mAh rating. I use them in mech with builds lower than what you are running and get a couple of hours of heavy use out of them. The last puff is SUBSTANTIALLY smaller than the first because the voltage drops constantly while you vape, but even the last puff at 3.5 - 3.6V is still enjoyable. Just make sure you get authentic Sony's. There are a lot of fakes out there. I get them from Illumin.com and orbtronic.com. $6-$7 each.

 

[suprtrkr]

Hi! Your experience is not normal. If your build is really .67 ohms and your batteries really 2900 mAh, they should last longer. You may have a bad charger, or your batteries may be worn out (they don't last forever.) As batteries age, and with use, they gradually lose their ability to hold a charge. I suspect this is what's happened to yours. This is one reason I always recommend a charger with a readout so you can determine how many mAh have been put back in the battery during the charge cycle. Watching this over the battery's useful life will give you a good idea when to think about replacing them without waiting for them to fail you when you need them, as yours are now doing. I use an Xtar VC4 charger, and I can recommend. Given you say your batteries are 2900 mAh, I suspect they are, at best, 15A CDR batteries. 2900 is a lot of capacity for a 20 amp battery. For my part, I always use Sony VTC4s in my mechanical mods. This is a native 20 amp battery that can be safely run to 30 amps without dangerous overheating, and I like the additional safety margin. They are, however, 2100 mAh batteries. Still, I am getting at least 10 times the life you are on them, and I coil between .5 and .7 myself.

 

[tj99959]

When it comes to battery life resistance is your friend. The higher the resistance ... the longer the battery charge lasts.
So it's the age old thing of 'everything in life is a trade off'.

No 1/2 hour on a charge is not normal. 2 hours on a charge is about average with sub ohm builds. (depending on how low the resistance)
At 0.7 I would expect about 4 hours at my vape pace using a 25r battery, and that would be swapping the battery out at about 3.5-3.4v.