This is the fourth in a series of articles exploring development of eVTOL batteries.
Batteries for emerging electronic vertical takeoff and landing (eVTOL) aircraft are still in a relatively early stage of development and maturity.
“Each OEM has its own design and configuration, including the type of cells used,” says Dr. Ionel Stefan, chief technology officer at Amprius Technologies Inc. “Standardization is maturing mostly relative to the safety standards, although differences exist between standardization bodies and OEMs, or from one region to another (USA, Europe, Asia). Electric mobility can be costly, but Amprius remains committed to commercializing high-power and energy battery solutions that enhance eVTOL use cases and increase cost-effectiveness.”
eVTOL batteries are in constant development to meet energy density and C rate requirements. Several manufacturers have already started working with the FAA and European Union Aviation Safety Agency to seek certification.
“The FAA and other regulators impose strict certification requirements around battery solutions approved for eVTOL use,” Terranova says. “From a regulator’s perspective, eVTOL batteries present a ‘big data’ issue with handling and computational challenges. How is the FAA going to ensure that the right amount of battery data is collected and analyzed after every flight to give the public the assurance that these batteries are safe to fly?
Some FAA standards for testing and installation of batteries in aircraft do exist. These include RTCA DO-311 “Minimum Operational Performance Standards for Rechargeable Lithium Batteries and Battery Design Testing Systems,” SAE AIR6897 “Battery Management Systems for Rechargeable Lithium Batteries Used in Aerospace Standards” and FAA AC 20-184 “Guidance on Testing and Installation of Rechargeable Lithium Battery and Battery Systems on Aircraft.” These regulations will inform new eVTOL-oriented regulations that provide more comprehensive oversight of propulsion batteries; Europe is also in the early stages of regulation.