Air taxi companies begin dueling publicly over standards for charging stations

By Paul Brinkmann|November 14, 2023

BETA, Joby each seek to recruit air taxi developers to their rival preferences

The charging station competition that broke into public view last week between BETA Technologies and Joby Aviation is evolving quickly, as each company seeks to elevate its preferred technology into an agreed-upon standard for the emerging electric taxi industry.

On Friday, Joby Aviation of California released voltage, ethernet and other specifications about its formerly proprietary plug-in charger design, the Global Electric Aviation Charging Standard. The document made good on Joby’s promise, issued a few days earlier in a Nov. 7 press release, to make details of its proposed universal charging interface “freely available to our industry.”

The Joby press release came out nearly simultaneously with one from Archer Aviation of California and BETA Technologies of Vermont, in which the two companies announced they would collaborate to make BETA’s rival choice of a standard “an interoperable fast-charging system across the electric aircraft industry.”

Also on Friday, Lilium, the Munich-based air taxi developer, joined Archer in saying it would adopt BETA’s preference, the Combined Charging System standard. CCS is also favored by some electric car builders in the United States, though not Tesla, which continues to dominate the electric vehicle market in the United States. The General Aviation Manufacturers Association (GAMA) endorsed CCS for use in aviation in a white paper released in August.

No matter the standard, these units must convert electric current from the grid so that it can be distributed through a cable to a plug inserted into an electric vehicle. Usually connected to the internet, the chargers also process data about the battery condition and the quality of connection between the battery and charging station, for example. Some of that data is then passed on to the company and the customer.

Having a single charging standard in electric aviation could avoid an early pitfall of the electric car industry, in which multiple charging methods and plug configurations emerged and, in some views, hampered the growth of the market.

“What we’re saying is, the specifications of this [Joby’s] charger can be used for any type of electric aircraft, if you use the freely available standard,” Eric Allison, Joby’s head of product, told me.

GAMA, in the Archer-BETA press release, said adopting a “unified” approach to charging “will help promote electric aviation’s development at scale.”

Joby pushed back on any notion that CCS has momentum. Allison noted that the automotive industry is drifting away from the CCS standard and is adopting the newer North American Charging Standard developed by Tesla. Indeed, on the same day as the BETA and Joby announcements, California electric car company Lucid Motors said it was dropping CCS for future cars in favor of Tesla’s standard starting in 2025. Ford and General Motors are among companies that have announced plans to do the same.

Two Joby stations have been set up, one at the company’s test flight center in Marina, California, and one at Edwards Air Force Base. BETA, meanwhile, says it has installed 14 stations, mostly at municipal airports but also at Duke Field, which is affiliated with Eglin Air Force Base in Florida. Work and planning are underway to install 55 more stations, the company says.

One thing Joby and BETA might agree on is that charging stations should be designed and built by the vehicle manufacturers, avoiding incompatibility issues that arose in the electric car industry when companies that did not make the cars decided to make charging stations.

Joby’s Allison told me the company will announce soon that other electric aircraft companies intend to also use the company’s standard.

The Joby and BETA designs differ in several ways. For example, Joby’s stations circulate more than electric current; they also circulate coolant through the onboard battery to maintain an optimum temperature for charging and to precool the battery for flight, during which lithium-ion batteries heat up. BETA’s charging stations have a separate coolant system, the company says.

Also, Joby’s charging stations are designed to charge multiple battery packs in different locations throughout an aircraft, Allison said. That’s because, on the Joby S4 tiltrotor, two battery packs are inside the wings and two are in forward nacelles, which Joby says was done to keep the batteries out of the fuselage and away from the cabin in the event of battery fires.

By contrast, Archer and BETA’s battery packs are in one location, and so don’t require a charger that can charge multiple packs.

One thing the rival stations have in common is that they both are connected to the internet.

Allison said Joby’s stations are equipped with cybersecurity software and hardware that isn’t present or necessary in the automotive industry’s CCS charging stations. He said data relayed between cars and charging stations could be vulnerable to hacking.

“We’ve designed our solution with that [cybersecurity] front of mind, so this meets the needs from a cybersecurity standpoint in a way that automotive standards don’t have to and, frankly, aren’t designed to,” Allison said.

For its part, BETA noted in a statement to me that “security of CCS has been extensively peer reviewed by governments, industry (aviation and automotive) and national labs at a global scale,” and added that it is “taking extensive measures to ensure the highest level of cybersecurity, from on-aircraft encryption to working with national labs and the USAF.”

Neither company mentioned the rival company or its favored standard by name. BETA said its “shared charging infrastructure offers numerous benefits over multiple proprietary protocols developed by ” other manufacturers. Joby said its standard is “optimized to support all types of electric aircraft” and said “that is not true of the alternative concept currently being proposed.”

Neither company responded to questions about why their announcements were made on the same day. In conversations with people in the industry, I was told that they are often communicating about issues like charging infrastructure and became aware of each other’s plans.