Following on from the recent “What is the best 18650 battery” blog post here, next up, we look at the chargers used for them.

“Which is the best charger” is another equally ambiguous question. With hundreds of choices of batteries and an ever growing list of manufacturers and specifications for chargers, the real questions and answers are very much the same. What do you want/need it to do, and at what price point?

To kick things off, we’ll look at function.

What should you consider when shopping for in a charger?

There are a few things you need as a minimum. Almost all chargers now come with reverse polarity, over charge and thermal protection. When choosing a charger, these should be the very least in terms of safety features that you should expect to see listed.  None of our chargers come without these.

What else? This will depend on the type of batteries you use, how many you have, and how fast you need to turn them around through the charger.

Lots of chargers now have 2Amp+ outputs in a portion if not all of their bays. The XTAR VP4 Plus Dragon that i use for example, will charge at 2Amps in the outer two bays. This is great for a quick turnaround of my favourite VTC5A batteries but not so great for my tiny RCR123A cells i use for lasers which prefer a 0.25A charge becuase its lowest setting is 0.5A. If you are unsure of what the charging limits are for your batteries, your supplier should always be able to supply you with the factory Datasheet. On there, you’ll find the maximum charging current. It’ll look like this;

Picture of LG HG2 18650 Datasheet

LG HG2 18650 Datasheet

As you can see, this is for the LG HG2 18650 battery. Its normal charge current is 1.25A so a normal 1Amp charge is fine but it will actually be fine with charging at upto 4Amps (many people are unaware of how high the current can be set for charging 18650 batteries. Some have upper limits of 8Amps!). Most chargers available to the public are not actually capable of topping out 18650 charging capacities.

The number of bays is also a worthwhile initial consideration. There’s no sense wasting money on a single bay charger if you use 4 or more batteries a day. In a fast moving world, something which offers the convenience of always having fresh batteries charged and available will save frustration. Consider the time it takes to charge your batteries and how many you need between charging. For me, i go through around 4 batteries a day so i have a 4 bay charger. This allows me to never have to worry about not having any ready. If you only use two each day, a 2 bay charger might be better.

Where you charge your batteries, or more so where you could charge them to make life easier is not a 100% necessary but certainly worthwhile consideration. The Nitecore range of battery chargers have been around longer than vaping and while their price point and robust design make them ideal for almost all uses, they’re hardly mobile; requiring a mains plug for operation. XTAR however, are very much mobile. Almost all of their main line of chargers are USB powered, taking a single or double micro USB power input meaning they can be used on the move and plugged into a car, a laptop, powerbank or anything else with USB power. Some can also be used the other way. Placing cells in it while unplugged, it can discharge them back out via USB output and act as a powerbank!

The normal features discussed above aside, some chargers go even further. Going back to my desk charger, the XTAR Dragon has an internal resistance check function. This is great for identifying any changes inside the cell or even faults. Among many others, it also has a discharge and refresh function, completely draining the battery then charging all the way back up. These functions do come at a higher price point but can prove useful for some users. Some chargers have Bluetooth monitoring (although i feel this is a bit of gimmick, because you should never leave charging batteries unattended). There is even a new charger coming from Efan in China (Efan Lux S4 Battery Charger) with a full LCD touch screen beside the charging bays. RRP on this is expected to be circa £149, an unprecedented amount for a 4 bay unit!)

Price – Budget is always key for retail buyers and you should always buy the best possible charger you can afford, from a reputable retailer. This goes some way to ensuring both good performance and reliability and as mentioned previously, should limit the need to buy more or upgrade in the future should your battery collection increase. Battery chargers have dropped in price considerably over the last few years and in a recent poll of over 2,000 of our customers, Nitecore and XTAR chargers came out on top with 88% of the votes between them. This is the result of their continued developments in spec and safety, along with overall design and performance.

Lastly, brand loyalty deserves a mention. Many people have a preferred brand, me included. Although we have traditionally exclusively supplied Nitecore products and only in the last year started supplying XTAR chargers, they have quickly become my favourite. Nitecore are a very good product at a very reasonable price point and my old D4 is still used at home 4 years on, but i prefer the aesthetic design of the XTAR products along with nicer screens and more data availability for very little extra in price.

You can find our full range of battery chargers from Nitecore and XTAR here

Of course, if you’re struggling to choose the right product for you we’re always available on email, or you can leave a comment below.


Ben – Sales Director.





This is a question we see a lot with sometimes ambiguous answers; whether or not you can take your 18650/lithium/vape batteries on holiday with you.

The short answer, is yes! There has never been a regulatory issue with taking batteries on holiday/abroad via air. That’s not to say there wont be in the future should people not abide by regulations set out by airlines. Should there be a rise in the number of incidents involving them, its probable that airlines will move towards a blanket ban or more harsh restrictions on them for the safety of the aircraft and its occupants.

We’ve done some digging and looking into the internal regulations from the Top 5 airlines leaving the UK to Europe and further afield and they have no issue with it, providing the following points are adhered to (and most of it is of course common sense!).

How to store the batteries for transport;

  • Pay special attention to ensuring that the packaging of batteries is secure and prevents short circuit (all of our cases are more than sufficient and are free with any order)
  • Protect spare batteries from ingress of liquids (this should be easy, as all liquids should be in plastic bags)
  • Ensure that any batteries travelling in a device are isolated (in other words, make sure the device is switched off and cant be accidentally turned on/activated)

The next part is specifically related to how they can be transported via air.

In your hand bagged/carry on luggage;

  • Batteries must be kept in the device, or;
  • Maximum of 4 spare batteries per person kept in original/secure packaging (max of 2 with Flybe)
  • Lithium metal batteries (Liion/Li-Ion) must not exceed a rating of 100 watt hours (i’ll come to this shortly)

In your checked baggage (hold luggage);

  • Batteries must be kept in the device and powered off.
  • No spares

Exceptions to the above are all Virgin, EasyJet and FlyBe flights where no batteries can be carried in the aircraft hold. Hand/carry on luggage only.

How to calculate Watt Hours

Almost all airlines, whether taking batteries on holiday or shipping them abroad place restrictions on batteries/cells above 100 Watt hours. To calculate watt hours, you take the mAh (millamp hour) rating of the cell, divide it by 1000, then multiply by the voltage. For the Samsung 25R, the calculation would be 2500/1000 (2.5) x 3.7, making the total watt hour rating 9.25W/h. Well under the 100W/h limit!

Please note that in the unlikely event that you are searched and the cells are discovered, it is your responsibility to be able to provide the ratings of the cell for calculation. With our compliance marking this of course isn’t an issue but if you are buying non-compliant cells elsewhere, the onus is on you as the passenger to prove the specification and output. Failure to do this will result in the airline confiscating and either destroying or charging for the storage of your batteries until your return.


Virgin Atlantic

British Airways




18650 UK has collated the information in this blog post from the Restricted Baggage and associated pages from the websites listed above and while correct at the time of writing, may be subject to change without warning or update here. Always contact your airline directly if you are unsure.

Hope this helps!

Ben – Sales Director


There isn’t really a straight answer; its very subjective and will depend on what you want it to do…

Let start with the basics

Why do we use 18650 and close relatives? 

The answer is quite simple. Energy density. Gram for gram, lithium based cells are far more powerful that anything else readily available that can be easily put in an out of a device by anyone familiar with nothing more complicated than changing the batteries in a TV remote. The other option is an integral battery but often when they fail or reach their “end of life” (normally several hundred charge cycles) the device is redundant with replacements either not available or not economically viable.

What should you look for in choosing a battery for vaping?

This is where things get a little hazy, because contrary to popular belief or what people on Facebook might tell you, there are many right answers, not just one. There are also many wrong answers.

First, put price at the bottom of your priorities and consider that you’re going to put this in front of your face/in your mouth. Is not paying an extra £1 to a reputable vendor rather than a hooky eBay shop really worth the risk?

Next, we need to look at what your needs are. You can have high discharge, or high capacity. You cant really have both. You can have a reasonable mix of the two, but any increase in discharge output (current, measured in Amps) will incur a capacity output penalty (measured in mAh). Do you want something that will hit hard all the way to empty (technically known as “low sag”) or do you need something that will get you through the day?

We’ll look at these separately below;

Discharge rate (constant current or “CDR” – Constant Discharge Rating, measured in Amps)

We stock cells that range between 1.5A and 40A output. The KeepPower 8A 18650 is a fantastic cell in its field, arguably one of the best and even though it will fit in some vape devices, it wont last more than a few seconds before something terrible happens. This is because the discharge rating is far too low to power a vape device. Its a torch/laser cell. This is where subjectivity comes in.

For regulated or mechanical devices, you need to select the right cell for the job and again, this is where its subjective and a little bit of Ohms Law knowledge is required (or you can cheat, and Google an online calculator). For the sake of simplicity, we’re not going to use pulse discharge ratings here. Just the CDR.

For example – you’re running a single 18650 mechanical device and you place a RDA with a 0.20Ohm coil(s) on top. With this “load” and a fully charged 18650 (4.2V), it will be drawing 21A from the cell. Consider a Samsung 30Q for instance; one of the top selling batteries in the industry. It’s Constant Discharge Rating is 15A. This puts you at almost double the rated discharge. It doesn’t mean its not a top performing battery, its just not right for this application. The Sony VTC5A and Vapcell VTC5D and VTC6A re-wrap however would be perfect, with ratings of 25A+

Capacity (how long the cell will last between charges, measured in mAh – Milliamp Hours)

Again, we have cells ranging from 1500mAh, to over 4000mAh. Everyone wants the highest mAh possible. Less time charging and the ability to carry less batteries is convenient, but its a trade off. You cant have a 4000mAh 30A 18650 cell (no matter how many times China put figures like that on a wrap!)

Broken down in the simplest possible way, an 8A 4000mAh cell will provide 1A of power for 4 hours. 2A for 2 hours. 4A for 1 hour. 8A for half an hour, and so on (so long as the current doesn’t exceed the maximum constant discharge rating)

The above has very little relevance in vaping, because its used in very short bursts, but you get the idea. More mAh, longer run time.

Internal Resistance

This is a mostly overlooked but actually fairly important factor. The lower the internal impedance or “resistance” of a cell, the easier it is to deliver its energy. High resistance cells will struggle to expend their energy efficiently, instead turning the pressure of not being able to discharge at the rate being requested by the device into heat. Low resistance cells are much more efficient, offer less voltage sag and this is where the “hard hit” bit comes from. Lower resistance = More instantaneous power.

Understanding Battery Codes

Our compliance markings aside, there are lots of markings on batteries. We’ll break them down to make them a little easier to understand;

  • IMR – Lithium Manganese – IMR is one of the most stable and one of the highest current producing chemistries. It has the lowest running temperature in comparable tests making it far safer than older ICR technology. Interestingly, a lot of re-wrap companies mark their batteries IMR, when they’re actually INR.


  • INR – Lithium Manganese Nickel – INR is probably the most common in vaping. It blends nickel and manganese to form the positive cathode, providing low resistance and the ability for high current output. A lot of effort is put into this chemistry by manufacturers, shown in the Samsung 25R and the LG HE2.


  • NCA – Lithium Aluminium – NCA is a much lesser used but still comparable chemistry to INR. It does away with the manganese element of the cathode in favour of aluminium. You wont get the high level discharge ability of an INR cell, but you do get a much longer run time and increase shock resistance. They’re currently being used by lots of e-bike manufacturers, and Tesla use them in their vehicles!


  • ICR – Lithium Cobalt – ICR chemistry is used for one purpose. Energy density. Unfortunately this comes at a cost and that cost is stability. It bugs me that cells with this internal chemistry are available individually to end users on eBay and Amazon because they’re of almost no use to the general public bar DIY pack repairers. The Samsung 26F for example (most often found in laptop batteries) has a wrap the same colour as the Samsung 30Q; they can be very easy to confuse. The 26F is a 5.2A cell (factory data sheet rating) which is of almost no use in vaping. Put one of these in a vape device and run it at above 20w and you’re almost guaranteed to have a bad time.


  • IFR – Lithium Phosphate – IFR (more commonly known as LiFePo4) has very specific uses and is rarely seen in vaping because of its super low energy density. There are some that can be discharged at very high rates however, often upto 30C (30x its capacity) The average capacity is about 1200 mAh, some are much lower. So for example a 30C rated IFR cell could be discharged at 30 x 1100mAh, so 33Amps! But, it wont do it for very long at all. They also have a voltage cut off of only 3.2v. Much higher than the normal 2.8v or even 2.5v of other lithium based cells.


So. Which is the best 18650 battery? The answer is easy. All of them, in their own little way. Take time to consider what you want from the cell and pick the cell most appropriate to your needs, not just what everyone on social media is shouting about!

I hope this serves to answer the question but if its left you with more than you started with, feel free to drop them to us via message or post on Facebook, below in the comments, or Email Us


Ben – Sales Director