The costs of running this huge site are paid for by ads. Please consider registering and becoming a Supporting Member for an ad-free experience. Thanks, ECF team.
  1. Volunteer to help with beta testing!

    We’re working on getting the site updates ready, but we’ll need your help to check the changes, make sure everything makes sense to you, and report any issues you see. If you'd like to volunteer to help with beta testing, click the link below. The first 20 people to respond to this thread will be added to the team!

    View thread
    Dismiss Notice

(9) Battery Basics for Mods; the Ultimate Battery Guide

Published by Baditude in the blog Baditude's blog. Views: 293269

Last update on: 4/16/2019

If you are considering purchasing a particular 18650 battery for vaping, just remember that...

  • there are none with a true continuous amp rating over 30A.
  • there are a lot of 18650’s rated over 3000mAh but none of them can be rated over 10A and many are rated a lot lower than that.
  • there are none rated at 3000mAh with a true continuous rating over 20A.
  • there is only one with 30 amps with more than 1500 mAh capacity (Samsung 20-S)
  • battery company pulse or "max" amp ratings are useless and can't be used to compare batteries between brands or models.

There is a LOT of technical information in this blog. I have tried to simplify the information for the average reader the best that I can. Please take a few days to read over and process this information to avoid information overload.

Li-ion (lithium) batteries remain our best solution for a high current rechargeable battery for e-cigarettes. They are not a perfect solution, but they are the best currently available. They can fail dangerously if abused or misused, at times spectacularly. Proper care and treatment keeps failures to a minimum, but even with the best of intentions, an unplanned and dangerous "energetic release of energy" may still rarely occur. As vapers we must accept that risk and learn how to reduce those risks by educating ourselves on proper safe battery habits, understand battery specifications, and learn which batteries to choose for the way we choose to vape.

As e-cig mod users, we depend heavily upon batteries to be able to vape. To assist novices to choose which external (removeable) battery to use in their mod I have written this guide. Our choices in batteries are Lithium Ion batteries, the same "chemistry" often used in cell phones, laptops, cordless power tools, high end flashlights, and remote control cars. However, there are multiple classes of Lithium batteries and only one class is really idealy suitable for vaping:

  • Lithium IMR or Li-Mn (Lithium Manganese) Many companies today describe their batteries as being IMR, but in truth they are likely a "hybrid chemistry".
  • IMR/Hybrid batteries -- Newer sub-class of Li-ion batteries consisting of IMR, INR, or NCR chemistry. Currently the most common and recommended battery type)
  • protected ICR Li-Ion (Lithium Ion) -- Considered to be obsolete for vaping today.
  • LiPo (Lithium polymer) batteries are the non-replaceable internal batteries in the eGo and regulated box mods. I will not be discussing them here other than to say they are not safer chemistry, and depend upon the protection circuitry of electronic mods to even be considered relatively safe to use. We aren't afforded the opportunity to choose which battery the manufacturer puts into these devices, so I won't waste space here discussing them further.

Guide to Battery Specification Terms:
Batteries can generally be broken down by two major characteristics or specifications: capacity (mah rating) and amps (current or power handling). Understanding these two characteristics must be understood to make an educational choice between battery models.

When choosing which battery to buy we must pick which characteristic is your priority for the application that you will use it. You can't have both the highest mah and highest amps in one battery. This is due to the limits of current battery chemistry & technology. (Safety should always be your number one priority.)

Capacity or mAh Rating
- an approximation for how long a battery charge should last from 100% charge to when the battery will cut off. Roughly, 100 mAh = 1 hour usage with low drain applications like a flashlight. With the higher performance demands of most vape gear today, your estimation of how long the battery will last between charges will be lower than that.

The "best battery" is not always the one with the largest mAh rating. In most vaping applications a higher amp rating (CDR or continuous discharge rate) determines the better battery.

Amp Rating - or "continuous discharge rate" (CDR). In layman's terminology, this is the maximum current available of the cell.

Technically this is the maximum electrical current at which the battery can be discharged continuously before the battery will fail. This specification is set by the manufacturer, and is a standard measurement in the industry.

The "pulse or burst discharge rate" is not a standard measurement and varies from one manufacturer/vendor to another, making comparisons from one company to another company impossible, and therefore should never be relied upon. Be wary that an advertizer or vendor may describe their battery using a pulse rating; find out what the "continuous discharge rating" is (CDR).

The CDR isn't a suggestion.
It's the safe operating limit of the cell.

Basic rule of thumb at the moment, to get CDR amps you have to sacrifice mAh and run time. To get more mAh and run time you have to sacrifice amps and CDR. You won't find a battery which has both the highest amp rating and highest mAh capacity; that's the way it works with batteries.

:danger: Beware of dubious marketing campaigns which over-rate their battery amp ratings. These disreputable vendors and manufacturers are usually of the aftermarket or re-wrapper category. These companies attempt to confuse consumers with "max amp" specifications. Chinese brands like Efest, IMREN, MXJO, AWT and the "---- Fire" brands are the worst perpetrators of this practice. Don't fall victim to their advertising scams.

Are You Using a Rewrap (Rebranded) Battery?

Look specifically for the continuous discharge rate (CDR) in the battery specifications. Burst or pulse ratings are just that, they can do a high amperage for less than 1 second, but longer than that you begin to damage the cells. You want to choose batteries by their "continuous" rate, never for their burst. This is the danger of sub-ohming and not knowing the ins and outs of your batteries.

Any “max” or “pulse” rating is useless unless we know the length of the pulse, the time between the pulses, and the criteria used to set the rating (Voltage sag? Temperature? Run time? A combination of those?). Without knowing this, and all companies using the same pulse lengths, rest times, and criteria, we can’t use the max/pulse ratings for comparing any batteries. They are useless.

Battery Amp Ratings: Continuous vs Pulse Ratings
Battery pulse ratings are useless! | E-Cigarette Forum
There are no 18650 batteries with a genuine rating over 30A!

Technical discussion of a Purple Efest battery venting incident in a regulated mod

  • If you use standard resistance coils (1-3 ohms), either with a mechanical mod (no electronic chip) or low wattage (<20 watts) regulated mod (electronic chip), then you could choose an battery with more mAh capacity as your first priority. You won't need more than 10 amps CDR using this resistance, but you should still still use one with a minimum at least 10 amps. Generally speaking, comparing two batteries with the same CDR but different mah ratings, the battery with more mAh (capacity) will last longer per charge than one which has less mAh.

If you use sub-ohm coils (<1 ohm) in a mechanical mod, or a high wattage (>20 watts) regulated mod, then the amp specification becomes your top priority. Once you find a group of batteries with the necessary amp rating, then choose from that group the battery with the higher mAh rating. Coils under the resistance of 1.0 ohm require more amp current due to their higher amp draw. Later in this article I will explain how to determine your personal amp requirement.

Mooch's Recommended 18650-size Batteries

Samsung 18650 30Q, 3000 mah 15 amp CDR [​IMG] *
Sony 18659VTC6 3000mAh 15 amp CDR [​IMG] *

LG 18650HG2 3000mah 20 amp CDR [​IMG]

Sony 18650VTC5, 2600 mah 20 amp CDR [​IMG]
LG 18650HE4 2500 mah 20 amp CDR [​IMG]
Samsung 18650-25R, 2500 mah 20 amp CDR [​IMG]
Sanyo UR18650 NSX, 2500 mah 20 amp CDR [​IMG]
Sony 18650VTC4, 2100 mah 23 amp CDR [​IMG]
Sony 18650VTC5A, 2500 mah 25 amp CDR [​IMG]

Samsung 18650-24S, 2500 mah 25 amp CDR [​IMG]

Molicel 18650-P26A, 2600 mah 25 amp CDR [​IMG]

LG 18650 HD4 2100 mah 25 amp CDR [​IMG]
LG 18650 HD2 2000 mah 25 amp CDR [​IMG]

LG18650HB6 1500mah 30 amp CDR [​IMG]
LG18650HB2 1500mAh 30 amp CDR [​IMG]
LG18650HB4 1500mAh 30 amp CDR [​IMG]
Sony 18650VTC3 1500mAh 30 amp CDR [​IMG]

Samsung 18650-20S 2000mah 30 amp CDR [​IMG]

Manufacturer's CDR is 15A. The Samsung 30Q datasheet (Section 7.9) mentions operation at 20A. Operation at that level can be done as long as we don’t let the battery get above 75°C, its maximum rated operating temperature. This holds true for the Sony VTC6 battery as well. These are not a high performance “power” cell, designed for high current. They are a high capacity “energy” cell designed for low to moderate power levels and long running time. At higher current levels the voltage sag and power loss in the cell are huge. Do not exceed 20A.

Mooch's Recommended 21700-size Batteries

Samsung 21700 40T 4000mAh 25 amp CDR [​IMG]

Molicel 21700 4000mAh 30 amp CDR [​IMG] (best all around 21700, a bit wider in diameter than other 21700's)

Samsung 21700 30T 3000 mah 35 amp CDR [​IMG] (highest amp rating for a 2100)

Samsung 21700 50E2 5000 mah 10 amp CDR [​IMG] (highest capacity 21700, but only 10A, must have "2" on third line of battery)

Mooch's Recommended 20700-size Batteries

Sanyo 20700 NCR2070C 3500 mah 30 amp CDR [​IMG]

Sanyo 20700 20700B 4000mAh 15 amp CDR
[​IMG] (best if used under 10A and under 30 watts)

Molicel INR20700A 2800mAh 30 amp CDR [​IMG]

Unregulated Mechanical Mods

Use the appropriate battery with an adequate amp rating specification depending upon the current draw of your coil build (*see the chart immediately below for coil amp draw vs amp rating).
* Coil amp draw from Ohm's Law calculations for Mechanical Mods:

1.0 ohm = 4.2 amp draw
0.9 ohm = 4.6 amp draw
0.8 ohm = 5.2 amp draw
0.7 ohms = 6 amp draw
0.6 ohms = 7 amp draw
0.5 ohms = 8.4 amp draw
0.4 ohms = 10.5 amp draw
0.3 ohms = 14.0 amp draw
0.2 ohms = 21.0 amp draw
0.15 ohms = 28 amp draw
0.1 ohms = 42.0 amp draw
0.0 ohms = dead short = battery goes into thermal runaway

Learn how to find your specific battery's amp rating, and how to determine the amp draw of your coil by using an Ohm's Law Calculator. Explain it to the Dumb Noob: Ohm's Law Calculations

Regulated Electronic Mods

On a regulated mod the coil resistance is essentially irrelevant. What dictates the amp draw on the battery is the wattage you set
with the processor chip. Calculating battery current draw for a regulated mod If using a high wattage regulated mod, use a 20 - 30 amp CDR IMR battery, which ever your mod's manufacturer recommends. The wattage setting that you plan to use on a regulated mod will determine the amp requirement in this application, not the atomizer resistance.

I'll repeat, with a regulated device the resistance of the coil is irrelevant. Regulated mods separate the input and output voltage, in other words they separate the battery from the atomizer. The only relevant value is the wattage, and the remaining voltage in the battery. The wattage is generated by the mod by multiplying the volts by the amps. As the voltage falls, the mod will increase the amp draw to maintain the selected wattage from the remaining voltage level.

Are you using a single, dual, or triple battery mod? In the interests of keeping things simple:

-If you use a good quality 15 amp CDR battery like the Samsung 30Q or Sony VTC6, then you are good up to 45 watts per battery; 90 watts using two; 135 watts for three batteries.

-If you use a good quality 20 amp CDR battery like the LG HG2 or Samsung 25R then you are good for 60 watts per battery. If using a 2-battery regulated mod, you're good for 120 watts as you have two batteries. If you are using a 3-battery mod, you're good for 180.

-If you use a single 25 amp CDR battery like the Sony VTC5A, then you are good for 75 watts per battery, 150 watts for two batteries, and 225 watts with three.

-If you use a single 30 amp CDR battery like the LG HB6 you are good up to 90 watts; with a pair of 30 amp CDR batteries you could safely do 180 watts.

(Total wattage doubles using 2 batteries; Triples using 3 batteries.)

Up to 45W:
Samsung 18650 30Q, 3000 mah 15 amp CDR [​IMG]
Sony 18650VTC6 3000mAh 15 amp CDR [​IMG]
Up to 60W:
LG 18650HG2 3000mah 20 amp CDR [​IMG]
LG 18650HE4 2500 mah 20 amp CDR [​IMG]
Samsung 18650-25R, 2500 mah 20 amp CDR [​IMG]
Sanyo UR18650NSX, 2500 mah 20 amp CDR [​IMG]
Sony 18650VTC5, 2600 mah 20 amp CDR [​IMG]
Sony 18650VTC4, 2100 mah 23 amp CDR [​IMG]
Up to 75W:
LG 18650 HD4 2100 mah 25 amp CDR [​IMG]
LG 18650 HD2 2000 mah 25 amp CDR [​IMG]
Samsung 18650-24S, 2500 mah 25 amp CDR [​IMG]
Sony 18650VTC5A, 2500 mah 25 amp CDR [​IMG]
Molicel 18650-P26A, 2600 mah 25 amp CDR [​IMG]
Up to 90W:
LG18650HB6 1500mah 30 amp CDR [​IMG]
LG18650HB2 1500mAh 30 amp CDR [​IMG]
LG18650HB4 1500mAh 30 amp CDR [​IMG]
Samsung 18650-20S 2000mah 30 amp CDR [​IMG]

High Quality, Brand Name Batteries.

Not all 18650 cells are created equal. This is where the specific manufacturers and suppliers come into play. With few exceptions, there are only four major reputable manufacturers with specifications that you can trust: Lg, Panasonic/Sanyo, Samsung, and Sony.

There are many different "makers" of batteries who purchase second/third quality cells in bulk, put their own wraps on the cells, advertise inflated specifications, and charge an arm and a leg for what is in truth a "lesser" battery. Don't fall for their hype.

I recommend buying only the batteries from the lists below by LG, Samsung, Sanyo, or Sony, paying particular attention to model numbers and their specifications. After the manufacturer and model number, the capacity is listed next and the tested amp rating is listed last.

If the battery you are currently using is not shown in Mooch's Recommended Batteries chart, its because his tests revealed that it didn't meet its advertised specifications, or became too hot during his bench testing to be considered safe.

ECF battery geru @Mooch has been doing independent battery testing since 2016. Before you purchase a particular battery, look for the results of how that battery tested in the below link:

  • Lower Quality Brand-Name Batteries. Trustfire, Ultrafire, and Surefire are a lower-tier name brand battery in terms of quality and safety. Not recommended. The same goes for AWT, Basen, Cloud Chaser, Efest, Imren, MXJO, and Vappower brands, among others. Independent tests have revealed that these have over-rated specifications from what is advertised. Most of these brands are considered "re-wraps".
What is a "Re-Wrapped" or "Aftermarket Battery"?
There are many battery companies that are not actually manufacturers, but are simply companies who rebrand other manufacturer's batteries. Meaning, they do not make their own cells and are just buying cells from other manufacturers and “rewrapping or rebranding" them with their own plastic wrapper that has their own brand name and their own logo. Also known as "aftermarket" batteries.

While Lg and Samsung/Sony/Sanyo headquarters originate from Korea and Japan respectively, most aftermarket batteries come from Chinese companies. The first thing vapors must realize is that many of these brands have nothing to lose, and can make greatly exaggerated claims regarding performance with no bad fall back. There is no authoratative organization which keeps the battery industry honest. They make a LOT of money for very little work and generally charge more than the original manufacturer because they exaggerate their specifications as a means to trick consumers that their battery is better. Don't fall for their hype.

For example ultrafire will claim 6000mah capaicty in cells that are tested to be only 1000mah. Of course the other grossly exaggerated stat is the amp rating...and to sell to vapors, many of these companies will make outrageous specification claims. We really recommend that consumers just stay away from all aftermarket batteries. Here is a list of battery brands highly suspected of being re-wraps:
  • Efest
  • MXJO
  • AW
  • AWT
  • Boost
  • Sigelei
  • Imren
  • Ultrafire
  • Trustfire
  • Orbtronic
  • EH
  • GTL
  • Robiton
  • AWT
  • EagleTac
  • AmpMax
  • Basen
  • BattEnergy
  • EnerPower
  • Fenix
  • Intl-outdoor
  • Redilast
  • Xtar
  • Generic Batteries. Not recommended. "No name" or an off brand printed on the wrapper. Seen at FastTech, Amazon & EBay at cheap prices or thrown in for free in a kit when you purchase a mod from China. These are unknown batteries of unknown quality by an unknown manufacturer, and not worth the risk using in your mod. Never assume because they were included with your mod that they are safe, or the correct battery to use. Do not harvest batteries from an old laptop computer.
  • Counterfeit Brand Name Batteries. Be cautious when shopping for batteries, particularly if not using a well known, reputable supplier who specialty is batteries.

  • If uncertain about the quality or type of a battery, don't buy or use it. Do not use over-the-counter alkaline batteries (wrong chemistry) like those from Radio Shack, etc. To insure getting authentic name brand IMR batteries, buy only from trusted e-cig/flashlight vendors such as:
  • Use the type of battery that your mod calls for.
  • Battery Chargers. Get the best charger that you can reasonably afford, again from a reputable e-cig vendor. Statistically most battery incidents occur while batteries are charging. A higher end charger will have better built-in protections.
Pila, Xtar, Nitecore, and Efest are the most recommended charger brands. Recommend batteries be charged on a flame-resistant surface: stove top, marble countertop, metal baking pan, pyrex glass dish. Do not charge batteries if you are not physically present to keep an eye on them.

Guide to Choosing a Li-ion Battery Charger

Many of today's higher-end box chargers have "intelligent" technology designed for the charger to shut down when the battery reaches full voltage (4.2 volts), however electronics can and do fail. Don't trust the safety of your home & family to a faulty electronic circuit or charging cord.

Charging external batteries in the mod via USB port

Rest batteries after charging
One commonly-reported factor in almost all the incidents we hear of where batteries failed violently while in use is that they were taken directly off the charger and then used immediately, at which point they failed.

Because of this, we think it may be a good idea to rest batteries after charging them. This advice will not be found in the usual 'reference bibles' on batteries, but we see more and different reports than others. Therefore we now advise:

Do not use batteries directly after charging them. Use a battery or batteries you previously charged, and that have rested for several hours. This is especially important if using a stacked pair for higher voltage, as statistically the risk is far higher.​

(The above suggestion is based on anectdotal observation only.)​
  • Always use safe battery practices and common sense with all batteries. Even the safest battery available to us can fail. IMR battery failure Most common user-error battery failures are the result of too fast of a discharge -- from the fire button inadvertantly pushed for too long, or the battery being shorted from metal objects (keys, change, etc), completing the electric circuit when carrying a battery in a pocket or purse. Use plastic Battery Cases. Do not stack batteries unless your mod was actually designed to use stacked batteries.

  • Long term storage of unused batteries should be done in a dry place at room temperature (69 degrees F) at 40% voltage. Dispose of old unused batteries at a recycling center such as Radio Shack or Hope Depot.

Routinely Check Your Battery Wraps and Insulation Rings for Damage -- Extremely Important!

The plastic insulation wraps are very fragile, so if you are not careful when installing/removing batteries from the mod/charger, that plastic can tear exposing the bare metal of the "can" or cell. That exposure of bare metal is what can create shorts to the battery. The insulation rings on the positive end of the battery also protect the can's metal surface from making contact with a metalic surface, also resulting in a short.

Batteries and charger may get warm to touch; that is relatively normal. Neither should feel hot to touch; not so hot that they become uncomfortable to hold for 30 seconds.

Are your battery wraps and insulator rings intact?

Why Repairing Batteries With Cracked Wraps Is Absolutely Essential

Battery tears

You might ask why do battery manufacturers use such a fragile wrap? Well, remember, the batteries we use for vaping were never intended to be used like we use them. They were designed to be used in battery packs for the auto industry and power tools...never intended to be removed and re-inserted frequently like we vapers do.



All of these batteries are in urgent need of repair. Do not use until repaired or replaced.

In addition, don't use a battery that has become dented from physical abuse. It can't be repaired, so dispose of it properly and purchase a replacement.


About the Battery Manufacturers's Warning to Not Use Them in E-Cigarette Devices

New vapers might believe that the 18650 batteries we use for vaping were designed with us in mind. Nothing could be further from the truth. In fact, manufacturers like LG, Samsung, and Sony would rather we not use their batteries in electronic cigarettes.


These batteries were exclusively designed for the auto industry and power tool industry. They were designed to be used only in battery packs. These battery packs have their own custom-designed battery management system (BMS) that ensures configurable, consistent protection at desired current, voltage, and temperature settings to ensure long battery life and to ensure their safe use.

[​IMG] Battery Packs with Battery Management Systems


As vapers, we are primarily using single battery cells alone by themselves, which often means we may be using these single cells at or above their recommended specifications. This application is not the manufacturer's intended use for these cells. They were never meant to be used alone or singly. BMS's have their own safety circuitry and in some cases a temperature control circuit. This is why you may see warnings that these batteries are not for e-cigarette use.

However, these batteries are the best option that we have for high power in a smallish package. They become available for our use only when there is a surplus from warehouse depots who then offer them for sale to suppliers in the battery market trade.

If we have personal knowledge about these batteries by doing our homework, consistantly using safe battery practices, and not abusing them, then we can knowingly "accept the risks" involved and limiting the chances for error that could result in a catastrophy. Nearly all battery incidents are the result from "user error".


Mods, Batteries, & Safer Vaping

Basic to Advanced Battery Information from Battery University

PBusardo's Mod Battery Information Guide

IMR Battery Specification Comparison

A Beginner's Guide to Lithium Batteries

Are You Using a "Rewrap" Battery? Exposing The WORST Brands In ...

18650 Battery Buying Guide for Vapor Users

What does IMR mean?

Sub-Ohm Vaping: Discussion, Safety, Battery Info, Warnings

Battery Data | Deus Ex Vaporis

God of Steam's Getting Started: Battery Basics

What does a battery's C Rating mean?

Battery Specifications and Online Calculators

Exactly why 18650 battery names like VTC4, VTC5, Samsung 25R, are confusing everybody

Green Samsung 18650 25R5 vs. Blue 25R2

Best 18650 Battery (2015)?

Best 18650 Battery for 0.2 ohm?


ridemywave, JoAnnW, TuanOri and 12 others like this.
  • moondragon
  • Scarey
  • throwback8
  • tenshi
  • Born2Hula
  • ndr_shogun
  • ndr_shogun
  • Baditude
  • softarno
  • MassiveKlouds
  • Pilot
  • PhoenixD
  • Baditude
  • PhoenixD
  • Nikkel
  • Baditude
  • Nikkel
  • Baditude
  • kathi17
  • Baditude
  • kathi17
  • 1wildman
  • Retro68
  • Baditude
  • brookj1986
  • Retro68
  • Baditude
  • brookj1986
  • ipodah
  • Baditude
  • ipodah
  • catilley1092
  • skyrose
  • Lwr32
  • Baditude
  • roosterado
  • ModBox
  • Baditude
  • crg31953
  • Libertine89
  • Baditude
  • Libertine89
  • Pinggolfer
  • Baditude
  • Pinggolfer
  • derekspencet48
  • Fictitious Character
  • Baditude
  • fishj
  • NicM
  • heyjohn
  • Tedjameson
  • Baditude
  • bittermelon
  • Baditude
  • RayofLight62
  • Acer50
  • T!nman
  • Shameless
  • bizzyb0t
  • Baditude
  • bizzyb0t
  • JoAnnW
  • rhammer186
  • Baditude
  • Darth Omerta
You need to be logged in to comment