The sky is the limit for city travel with Saft

As a number of advanced mobility companies prepare to launch air taxi services over the next few years, it is time to address their battery needs.

Flying cars are a staple of science fiction films, but we are now at the moment when the long-promised technology might only be a couple of years away from taking to the skies. Companies like Joby Aviation, Archer Aviation and Wisk are competing to transform city mobility, beating traffic jams with fleets of air taxis that will carry up to six people and a pilot.

Summoned with a smartphone app, these aircraft promise to get passengers from downtown New York to JFK airport in just seven minutes, rather than 49 minutes by road. They will deliver urgent medical supplies from city airports to rural clinics. And they will transform commutes, allowing people to live 100 miles away from the office and still be at work in 30 minutes. What’s more, the first vehicles are expected to be flying as soon as 2024 in cities including Paris, Los Angeles, and Dubai.

These ‘advanced air mobility’ (AAM) vehicles will take on tasks performed by helicopters today. But they will be cheaper, and therefore available to more people, as well as quieter, so they can land in residential neighborhoods, and safer, so pilots will require less training. They are also much better for the environment. All these benefits stem from a unique feature of these aircraft: they are electric.

Indeed, electrification could be seen as aviation’s third great revolution, after flight itself and jet engines. However, e-aviation will not be possible without safe, reliable batteries.

Big names ready for takeoff with batteries

The AAM revolution is being driven by a flood of investment. In 2021, $7 billion was invested in companies developing these aircraft, more than double the amount invested in the previous decade. By 2040, the market is expected to be worth $1.5 trillion per year, with 430,000 aircraft in operation.

That potential is what has attracted so many big names to the space. Joby Aviation is partnering with Toyota, which is advising on factory layout and efficient production. Amazon, seeing the potential to transform deliveries, has invested in Beta Technologies. Boeing, Rolls Royce, United Airlines, Microsoft, and plenty of others are among those putting money into the space.

What they have all realized is just how transformative e-aviation can be. Changing the power source radically changes aircraft design. Today’s aircraft look the way they do because of the combustion engine that powers them. Efficient jet engines must be big, so even the largest airliner only has a maximum of four. Electric engines can be much smaller, so a smaller aircraft can carry six, eight or even more. More engines provide more stability and mean there is little chance of an engine failure forcing a plane down.

Jet engines are also more volatile and prone to mechanical problems. Electric power, by contrast, is much more predictable and problems are easier to fix preemptively. That makes the planes easier and safer to fly, with greater amounts of automation. The pilot, therefore, requires much less training and experience to operate these vehicles, which helps keep costs down. 

The power to transform cities with Saft

The aircraft will be fully automated eventually, but there is some way to go before that happens. Meanwhile, the aircraft must be certified by aviation regulators and the necessary infrastructure needs to be built. We need to think about how air traffic rules apply, for example. And places must be found for these aircraft to land, which could be difficult in crowded city centers. Finally, they need power on-hand at those sites, so that they can charge like electric cars.

This will require batteries that are safe and reliable, much more so than the battery in a smartphone, for example. These vehicles will all need to recharge their batteries quickly on landing, which would put too much strain on the grid. Therefore, they will need to be served by energy storage systems, which are effectively large batteries that take power from renewable energy sources and store it until it is needed for charging. Onboard, the aircraft needs the lightest, smallest battery possible. Size and weight will be vital for the operational flexibility that will make these aircraft a success.

At Saft, these are challenges we have been thinking about for years. We specialize in safe, reliable batteries for highly specific and demanding uses, such as mining and deep space. We have concluded that e-aviation batteries must be lithium-ion based. Other technologies, such as solid-state batteries, will not be ready to meet the 2024 launch date that the most advanced companies are targeting. For AAMs, we’re blending different lithium chemistries to create a battery that combines energy and safety, and that can be manufactured at scale.

Eventually all aviation has the potential to become e-aviation, though the largest aircraft will operate on hybrid power at first. That is years away but the revolution in urban transport will unfold over the rest of this decade. It will reshape our cities and change our lives. Now is the time to think about how we power this revolution.