E-cigarettes are a technological marvel; there’s no doubt about it. The genius of Hon Lik was to transform smoke into vapor, switching the tobacco for a nicotine-containing liquid, the fire for a tiny atomizing heater and coming up with arguably one of the most significant pieces of harm reduction technology in human history.

But the tide of e-cigarette innovation doesn't stop there; in fact, Hon Lik just got everything started, leaving an army of dedicated modders and technological wizards to add features such as variable voltage, adjustable throat-hits, puff-counters and a whole host of other cool features.

For all this innovation, though, there are still some technologies vapers would absolutely love to see which are conspicuously absent. The main improvements are likely to take the form of improved manufacturing processes – to keep things like the heavy metal content of vapor to an absolute minimum – but in some areas, e-cigs are still in need of some high-tech innovation. Here are the top five technologies we think e-cigs are missing.

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5: Split Tanks

They say variety is the spice of life, but it’s never as true as when it comes to e-liquids. We all have a collection of liquids on a virtually constant rotation, as we tire of one; we make the switch to a different flavor and keep on vaping. The only problem is that to make the switch between flavors we either need to vape through the remainder of the liquid in our tank, have a spare loaded and ready to switch it with or take the risk and make a potentially horrendous mixture of flavors.

That problem could be solved for good with the option of a “split” tank. Not like the Splitfire Tank, more of a literal double-tank, where you can load one liquid into one side and another into the other side, giving you a choice of liquids at any given time. Since each would need its own atomizer (lest you just wind up getting a mixture of the two liquids) the resulting split tank would be a chunky beast, but it would open us up to a new world of vaping. It would work better with a dedicated, dual-firing APV, and the metallic tubes at the top of each atomizer could have an L-bend and meet up in the middle under the mouthpiece. If somebody accomplished that, not only could you switch between liquids at will, you could also combine them into a single stream of vapor by double-firing.

4: Wireless Charging

Wireless charging systems are on the cusp of becoming commonplace. They basically work on the relationship between electricity and magnetism, and the idea was first proposed by geek idol Nikola Tesla.

The technology comes from the fact that a moving electronic current creates a magnetic field, and a changing magnetic field can produce an electric current. To wirelessly charge, the device in question is fitted with a receiver coil, which picks up magnetic fields in order to generate voltage. This is then used to charge the device. All that’s required to complete the process is a transmitter coil, which is pumped with Tesla’s own AC electricity to generate the magnetic field. The technology is already being implemented in Starbucks (to charge mobile phones, of course), but also holds significant promise for e-cigs. The days of USB charging – being tethered to your computer like a 21st century slave – may well be numbered, especially if vapers could join serial smart-phone users and pop their e-cig down to charge on coffee-shop tables while they sip an over-priced drink. The only current problem is a limitation on range and power, but improvements are inevitable and it’s only a matter of time before e-cig manufacturers pick up on the idea and run with it.

3: Solar Cells

Power is understandably one of the biggest concerns for e-cig users, since the technology is entirely dependent on a steady flow of electricity. Solar power is the ultimate renewable source of energy, because the Sun does the work for us, all of the time, providing us with around 1367 watts per square meter of the Earth’s surface. All we have to do is learn to make use of that energy – and photovoltaic cells give us the power to do just that. Everybody is familiar with the solar panels they’re ordinarily used for – and indeed, e-cig charging cases have been made which incorporate them – but there’s also the possibility of tiny, glitter-sized solar cells which pack a whole heap of power in the same way.

Ordinarily, individual solar cells are around six-inches square, but the newly developed ones are a mere millimeter (0.04 inches) across – or even smaller. The everyday applications are immediately obvious – hell, a flexible “fabric” of photovoltaic cells could be woven into clothing, making you a portable charging device! Alternatively, if e-cig designers decide to incorporate the technology, your e-cig battery could be studded with almost imperceptibly small solar cells, and charge itself anytime you have it out in the sunlight!

2: PG and VG-Free E-Liquid

All of the technological advances might lead you to forget that e-cigarettes are originally intended to reduce the harms associated with smoking. Of course, they’re succeeding fantastically in that department, but there’s still room for improvement. One of the most pressing concerns is that formaldehyde can occur in the vapor from some e-liquids in the same quantities as it’s found in tobacco cigarettes. Chemically speaking, propylene glycol can turn into formaldehyde when heat is supplied – which means this happens in many e-cigs.

Similarly, the oxidation (loss of electrons) or hydrolysis (splitting with water) of glycerin (like vegetable glycerin) can lead to the formation of formaldehyde. This represents one of the most important areas for the future development of e-cigs. Although the risks from e-cigs as a whole are significantly reduced in comparison to smoking, the use of a different chemical in e-liquids could give e-cigs the power to transition from being relatively safe to being absolutely safe. The composition of this new futuristic e-liquid is open to guesses, but it’s a virtual inevitability that one will – and should – be developed.

1: Graphene-Based Batteries

Lithium-ion batteries are standard in e-cigs, but there is plenty of room for improvement with the technology. Undoubtedly, battery-life is one of the biggest issues facing e-cigs, and although the improved charging methods above would help, what we really need is a better battery overall. This may come in many forms, but one of the most promising is graphene, which is basically an atom-thick sheet of carbon arranged in a hexagonal pattern, and when incorporated into batteries (possibly combined with tin oxide electrodes) they offer substantially improved battery life, performance and charging time. It would take the time required to charge an e-cig down to just a few minutes, and designs like this were already on show at the 2013 Consumer Electronics Show in Vegas. Graphene hasn't necessarily won the battery war yet, though, since things like niobium-oxide and lithium-sulfur options are still vying for the position of the new battery of choice.

Whichever direction it takes, the new battery designs – when incorporated into e-cigs – represent a significant improvement to e-cigs as a technology. If they’re incorporated, you’d hardly ever have to go without a vape for ten minutes, even if you used a tiny, cigarette-sized battery.

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