Knowing the future to any degree of certainty, at least beyond the immediate, is next to impossible. Take the pandemic and the ensuing chaos it wrought: Few predicted it would actually unfold the way it did. But as hard as the future may be to dissect and discern, it is nonetheless a thing we continually obsess over. Electric cars are a good example. As a still-futuristic force on our nation's roads, EVs are one of the few windows into what we can expect from the world's new and established automakers in the next handful of years. But there remain many unknowns that experts disagree about. 

One such unknown: What does the future hold for EVs and the tires they roll upon? What can we expect in the next few years in terms of EV tire innovation and development? Although refinements and improvements will no doubt come to areas where we're already seeing some change, such as tire size and material content, what's next for the world of EV tires will be all-new and potentially game-changing. 

When it made its debut at the 2011 Frankfurt auto show, the BMW i3 concept stood out for its futuristic design, recycled interior materials, and, for the tire nerds among us, its large-diameter but narrow tires. 

"One of the trends for EVs you may start to see that we see a little bit of already is that the best tire for low rolling resistance is tall and narrow," Michelin product manager Steve Calder said. "So you may see EV manufacturers moving to that strategy of a taller and narrower tire. It has the good [visual] aspect of a large wheel and tire package from the side, but it doesn't have nearly the amount of aerodynamic drag or rolling resistance due to the contact patch shape. "

Another thing to consider with electric vehicle tire size and shape is that because EVs tend to be heavier than internal combustion engine (ICE) and hybrid vehicles of equal size, their tires have to cope with more weight. But car makers aren't always upsizing their EV tires to match, Calder said.

"One of the trends we're seeing is that they're not necessarily making the tire any larger," Calder said. "So when you think about the maximum load of the vehicle compared to the maximum load [capacity] of the tire, that gap is decreasing. It's still fine, but for the same size tire, electric vehicles are heavier even to the point where there's a new standard for high-load-capacity tires. "

Because tire sizes aren't necessarily increasing even as EV weights rise, that means it's often the tire's air pressure that has to climb to compensate. But increased air pressure "does produce additional complications for noise and comfort," Calder said. Clearly, today's practical challenges surrounding EV tire size, shape, and pressures will continue on into the near future. 

Just as important as the size and shape of the EV tires of tomorrow is what those tires will be made of. Beyond the need to generally reduce emissions and pollution for the sake of the planet itself, within the EV space, there's an extra push for green materials and methods given their zero-emissions mission. Accordingly, the tire industry is working to make its whole production chain as eco-friendly and sustainable as possible. 

"We're doing things [like] taking water bottles and recycling them so that we can use them in our textile cords," Michelin technical communications director Russell Shepherd said. "So it's pretty much the same material, but it's recycled." Other plastic post-consumer items are also being recycled to help with raw material production. 

"We're also using things like styrene from yogurt cups," Shepherd said, "and we're using that to create bio-butadiene. So while butadiene is normally an off-product of the petroleum industry, we're learning how to make that from bio sources. And that is a key component for rubber. " 

Of course, rubber itself is a natural product, but natural rubber is only part of the formula for a successful tire. "We're learning how to make synthetic rubber [sustainably]," Shepherd said. "For some of the things we're talking about, we like to use synthetic rubber. "

Michelin is also working to put recycled tires inside new tires. "We know how to break down the tire using pyrolysis (thermal decomposition occurring in the absence of oxygen) and recover carbon black, and of course, the metal and the steel [from the carcass]," Shepherd said. "And then we are working to get other sources for things like silica. "

Among the materials Michelin is working with is rice husk as a potential bio-based and sustainable tire formula. "The reason we like rice husk is because it's an offshoot of the food production system," Shepherd said. "One of the challenges that we have that we're very focused on is that whatever solution we propose doesn't compete with the food system. "

Many of today's new electric cars are already using the latest in cutting-edge automotive technologies designed to ease driver operation. Just beyond that lies the promise of true autonomous driving, and the next generation of tires is expected to aid in the transition. How, you might wonder, could something as old-school and seemingly low-tech as a tire — a literal hunk of rubber — help bring us into the golden age of autonomy?

The answer is surprisingly basic. When a human is driving a car, we naturally sense the grip level of the road and our tires. We can intuitively tell that snow and ice are slippery or discern the moment when our speed starts to cause us to hydroplane when the roads are wet. We vary widely in our ability to sense these changes accurately, but a car has almost no way to sense the grip of the road, and the tire none at all. Instead, most cars wait until a tire begins to slip before reacting. 

But future connectivity and computerization of the tire, up to and including new sensors and instrumentation integrated into the tire itself, may eventually allow the tire to directly sense the road's grip. This would make for safer and smarter self-driving autonomous cars, or potentially even cars with limited autonomous capabilities. 

"As vehicles become more connected, tires are also becoming more connected," Shepherd said. "There's just a natural link between electric vehicles and connectivity, and that'll apply to the tire. So in the future, with electric vehicles, you'll see tires talking to the vehicles and vehicles talking to tires. "