Battery and electric propulsion systems provider Dovetail Electric Aviation has partnered with global battery cell manufacturer Molicel.

Both companies are working together to integrate Molicel's advanced battery cells into Dovetail's proprietary battery system, DovePack. The collaboration marks a key step toward the certification and deployment of what will potentially be EU's first retrofit-ready electric aircraft and reinforces both companies' commitment to driving innovation in sustainable aviation.

Battery cells are the backbone of any electric propulsion system, influencing not only performance and safety but also efficiency and long-term economics. Dovetail's proprietary battery system, DovePack, is built around Molicel's high-power cylindrical 21700 cells, combining world-class electrochemistry with Dovetail's proprietary advanced immersion cooling technology to meet the rigorous demands of electric aviation. Dovepack has been designed to meet energy densities over 265wh/kg at the pack level with mass produced cells, not laboratory samples, with the potential to surpass 300wh/kg. Dovepack is the most compact battery system for aviation, thanks to its novel architecture based on immersion cooling, with initial testing showing the capability to pass thermal runaway tests under EASA and FAA standards. Dovetail is including DovePack in its certification roadmap, targeting its integration on retrofit flying platforms by the end of 2025, a full flight test campaign in 2026 and certification in 2027.

Engineered for the realities of flight, DovePack is designed to balance high power output, energy density and thermal stability within a scalable and certifiable architecture.

Molicel's cells provide the core energy and discharge capability for take-off, cruise and landing, while Dovetail's advanced thermal management and control systems keep cells within optimal limits across the flight envelope. This combination enables faster charging, longer lifecycle and lower cost per flight hour, which are essential for commercial viability.

As Dovetail and Molicel work towards future certification, initially under EASA and CASA, the integration of Molicel's proven cell technology into DovePack is helping ensure that future electric aircraft meet the safety, performance and efficiency benchmarks required for global operations.

As part of the collaboration, Dovetail has selected the latest of Molicel's high-performance cells for integration into its next-generation battery modules, DovePack. These will form the core (together with Dovetail's proprietary propulsion system, DovePower) of Dovetail's battery-electric powertrain, which will play a critical role in its early flight campaign and product certification roadmap. The companies are also exploring a long-term supply agreement to support future DovePack production for both internal and third-party aviation applications.

Molicel is a leading supplier of advanced lithium-ion cells with decades of experience in high-power, high-energy density and high-safety applications across electric vehicles, aerospace and energy storage. Known for its commitment to R&D and performance-driven cell chemistry, Molicel has earned the trust of innovators in industries where reliability and energy density are paramount.

Although Dovetail is also developing powertrains with third-party hydrogen fuel cells and range extenders, batteries are a central pillar of its propulsion architecture. DovePack's modular and scalable design enables integration into both full-electric and hybrid configurations, making it ideal for flexible mission profiles and multiple aircraft platforms.

“Partnering with Molicel allows us to accelerate the development and certification of our battery systems using a proven, high-performance cell technology,” says David Doral, CEO of Dovetail Electric Aviation. “As we move toward bringing retrofit electric aircraft to market before the end of the decade, we are excited to work with a cell partner that shares our values around safety, technical excellence and energy innovation.”

“Molicel's unwavering commitment to safety is at the core of our battery technology. Our intensive R&D efforts are deeply invested in shaping thermal behaviour and have successfully resulting in exceptionally low flammability for our cells. This makes Molicel ideally suited for the rigorous demands of aviation,” adds Casey Shiue, president of Molicel. “Our high-performance battery cells, combined with Dovetail's innovative DovePack system, will be instrumental in achieving certified, zero-emission flight. We are proud to contribute to a sustainable future for aviation.”

The partnership also paves the way for future collaboration in battery innovation, with the potential to integrate next-generation Molicel technologies into future versions of Dovetail's power systems.

Meanwhile, Hartzell Propeller has entered into a collaboration with Dovetail. Together, the two companies are working to integrate Hartzell's propellers and pitch control unit (PCU) into Dovetail's proprietary electric propulsion system (EPS), known as DovePower.

The partnership combines Hartzell's long legacy of innovation and certification in propeller technology with Dovetail's cutting-edge development of zero-emission propulsion solutions. The goal is to deliver high-performance, certifiable systems tailored to CS-23 category aircraft requiring over 500 kW of power – including Dovetail's first full electric conversion of the Cessna Caravan.

Hartzell's propeller and PCU are set to become a core component of DovePower, enabling precise thrust and control for high-powered electric aircraft. Dovetail has already conducted successful standalone testing of its electric propulsion system. Integrated tests with Hartzell's components are scheduled for the second half of 2025.

The joint system will power Dovetail's first electric Caravan prototype, which will be tested as a fully integrated platform in Spain under the Science and Innovation Missions Program, a major aerospace R&D initiative led by CDTI and supported by NextGenerationEU funds.

“Hartzell is proud to partner with Dovetail to shape the future of electric flight,” comments Hartzell Propeller president JJ Frigge. “By combining our expertise in high-performance propeller systems and lightweight, carbon fibre composite propellers with Dovetail's groundbreaking propulsion technologies, we're helping to redefine what's possible in regional aviation without compromising performance or safety.”