An e-bike revolution powered by carbon
Graphite, graphene going into faster, lighter, smarter bikes Metal Tech News Weekly Edition – July 15, 2020
Last updated 7/29/2020 at 3:34am
Providing the ability to traverse mountain trails or urban landscapes at blazing speeds and with less leg power, electronic bikes are now more than just a simple recreational activity, or even a low-cost and green transportation option for commuters.
While the overall concept of a bicycle has not changed much, today's e-bike manufacturers are advancing new technologies and groundbreaking materials to produce the fastest and smartest cycles ever made.
App-customizable automatic drivetrains, electronic suspension systems that adapt to changing terrain, wireless communication systems, near indestructible tires and longer lasting batteries with faster recharge capabilities are among the options being offered on today's bikes.
And almost by serendipity, all because of carbon-based materials such as the graphite that goes into the lithium-ion battery, graphene in the tires, and carbon-fiber frames are making the environmentally conscientious e-bikes faster, lighter, and stronger than ever.
Graphene infused tires
The full extent of what graphene can do for the world has yet to see even a drop in the bucket, yet specialized bike innovations that incorporate this material made from a single layer of carbon atoms are popping up around the globe.
Vittoria, an Italian bicycle tire manufacturer, has developed a line of tires that take advantage of graphene's unprecedented strength and durability to provide a more comfortable ride and extend e-bike battery life, thanks to their special graphene compound that can reduce rolling resistance.
The five tires in the lineup are the E-Randonneur (urban e-bikes), E-Barzo (XC), E-Aggaro (trail), E-Martello (enduro) and E-Mazza (enduro).
Vittoria's claim of extended battery and tire life appears to be aimed at e-mountain bikers, with the company saying their tires are equipped to withstand the extra weight and power of an electric bike.
This is due to their graphene compound. The '4C' layering technology they have developed, four unique rubber compounds into the same tire, which provides the durability and quicker roll of hard compounds and the grip and comfortable ride of softer ones.
This in turn means that the tire can better resist the more rapid accelerations coming from an e-bike, and a more durable tread that rolls well for longer, can positively effect battery consumption.
Aside from battery life, these tires are said to be more robust than ever before in terms of puncture resistance, with all of the tires receiving a two-ply casing with sidewall protection to better cope with the extra weight and power of an e-bike.
Further still, Vittoria has also designed an e-bike tire air-liner that, according to them provides "a tunable system that gives a progressive feel."
This essentially gives the wheels even more protection from impacts that can increase a rider's comfort and will allow e-mountain bikers to run their tires at even lower pressures.
These comfort and durability advantages could undoubtedly find their way into other tires.
Automobiles, freight, heavy machinery, and airplane tires, to name a few, may perhaps benefit from the developments that graphene tires have given to present and future e-bikes.
Graphene lube and frames
The same 2D carbon materials that are making e-bike tires more durable and roll better is going into a unique lube for bicycle drivetrains.
AbsoluteBLACK's GRAPHENlube is basically a wax-based water emulsion with a special mix of high purity graphene.
Applied as a liquid, it then dries and creates an extraordinarily durable and low friction lubricant that absoluteBLACK claims gives "free" power, meaning less work for you and the bike.
As wax-based lubricants exhibit a greater tolerance to water and dirt contamination, by successfully separating moving chain parts from abrasion and filling in imperfections on friction surfaces, graphene was found to be perfectly ideal as a medium of lubrication.
It has extremely low friction coefficient in all environments, is far stronger than any other material known to man, it adheres to metal protecting surfaces from excessive abrasion and it repels water and is not permeable by air reduction thus diminishing oxidative stress on metal surfaces.
Beyond maintenance, the material used in the body of a bicycle is possibly the single most important part.
For professional and competitive cyclists, a lightweight and strong frame can allow them to rack up miles and also have just that little bit of an edge with control and acceleration.
Bike frames today are made of one or a combination of four different materials: steel, aluminum, titanium or carbon fiber.
Steel has been the longest running material used in bicycle manufacturing for more than a century. With durability, affordability and easy maintenance, it is no hard guess why steel is still a top contender.
Aluminum was not widely recognized until the 80s, since then it has become the most popular of all frame materials.
If a bike's frame is manufactured with aluminum, you will get better construction and higher quality fabrication.
With titanium, comparative to aluminum, it is a less seen material as it is often more expensive than aluminum and more difficult to work with.
Lastly is carbon fiber, unique amongst the materials as it is not a metal, but a material composed of graphite and other substances woven into fibers.
The greatest merits of carbon fiber are that it can be molded into many different shapes and possesses an unbelievable lightness and rigidity which aids pedaling efficiency with incomparable comfort.
As carbon forms an extraordinarily strong molecular structure it works as an incredible shock absorber, so carbon forks are popular because of the lightness and its ability to absorb force.
So far, we have not seen it yet but as bike frames seek the pinnacle of lightness, carbon fiber frames being of the same family as graphene, it is purported that future graphene bicycles could weigh as little as 350 grams, or justly slightly more than a 12-ounce can of soda.
With present lightweight bike records resting around 5 pounds, the difference is night and day!
The future of graphene does not end there, however, with electronics, microchips, batteries, motors and possibly more, a graphene built, powered, and lubricated bike could be as fast, if not faster than low-end vehicles, lighter than a can of Coke, sturdier than a dual stack diesel, and far better for the environment.
The prospects of graphene should be exciting for any cycling enthusiast.
Powering the e-bike
Often you can see in major cities, stations of cheap e-bikes or bikeshares where one can swipe a card and off you go.
With speeds between 15 and 30 miles per hour, and a battery life range of 40 to 60 miles, these affordable and mass-produced e-bikes show the extent of how easy it has become to introduce to the average consumer cheap transportation, yet what really powers them?
Presently, there are several different styles of e-bike motors that range from electromagnetic power to direct powered gears yet overall, they are designed to do the same thing, saving you from being exhausted before you get to the top of that hill.
Simple crankshafts, gearboxes or copper coils, powered by rechargeable lithium-ion batteries, offer varying levels of power or torque to get you where you need to go.
It has become so simple that there are even do-it-yourself motors you can install onto your standard leg-powered bikes. If you are technically inclined and do not mind getting your hands dirty, almost any bike can be retrofitted.
Of all the various methods, two prevailing styles have made the cut, mid-drive motors and hub motors.
For your typical bike, you can easily recall the mess of teeth on the rear tire where the chain rests. This becomes the location for hub motors and takes the place of your legs.
Mid-drive motors, however, are nestled between where the pedals would be located, each have their pros and cons but as more smart bikes become developed, to reduce weight and maintain balance we may see a shift towards mid-drive e-bikes.
As for batteries, with current technology, average weight is between 6 to 8 lb and delivers a 20-mile range estimate.
Hard to imagine a 12oz carbon fiber bike being weighed down by a bowling ball, yet that is the wall for present batteries, one can only hope we can see more powerful and lighter batteries in the future.
Though varying styles and types exist, the fact of the matter is they are cumbersome and that is the tradeoff for now.
Perhaps with the prospects of what graphene may do for future battery technology, it could solve that too.
Needless to say, the options are now more than ever for cyclists, competitive, recreational or otherwise. With some manufacturers treating their bikes not unlike top luxury vehicles, the care and dedication towards this timeless transport device will only continue to grow.