ARPA-E Archived Funding Opportunities

DE-FOA-0002972: Request for Information (RFI) on Rethinking Energy Storage Technologies for Planes, Trains & Ships: “Battery 1K”

The purpose of this RFI is to solicit input for a potential future ARPA-E program focused on energy storage technologies that can deliver a specific energy equivalent to, or exceeding, 1000 watt-hours per kilogram (Wh/kg). Of particular interest are technologies that are not extensions of current mainstream electrochemical device thinking or short-term technology road maps. The goal is to gauge the potential to realize exceptionally high-energy storage solutions that would be capable of catalyzing broad electrification of the aviation, railroad, and maritime transport sectors. ARPA-E is seeking information at this time regarding transformative and implementable technologies that could accelerate electrification of transport including the following industries:

  • Aviation: “Battery 1K” can enable regional flight on aircraft transporting up to 100 people.
  • Railways: “Battery 1K” can enable cross-country travel in the United States (U.S.) with fewer stops while also reducing the amount of infrastructure needed for charging/refueling.
  • Maritime: This is a diverse category, but higher energy density options will open up additional electrification possibilities.
  • Trucks: Strategies and plans to electrify this sector are in place, however, “Battery 1K” would enable longer range and higher freight loads.

Upon consideration of metrics discussed in the RFI, the traditional energy storage device “playbook” must be cast aside. An overwhelming majority of batteries “live” in boxes, are “plugged-in” to charge, and in the case of personal passenger electric vehicles (EVs) are used only 5% of the time. For the remaining 95%, EVs are typically parked with a battery that is either idle or charging slowly. In sharp contrast, for the transportation sectors of interest to this RFI, the energy storage device may be required to (1) operate continuously over extended periods of time, (2) refuel/recharge/reset rapidly, and (3) achieve exceptional longevity. It is also worth noting that constraints on volumetric energy density are reasonably anticipated to be dependent on the specific application, although perhaps less important than gravimetric energy density in the case of aviation, for example. Certainly, an energy storage technology that can deliver ≥ 1000 Wh/kg and ≥ 2000 Watt-hours per liter (Wh/L) would represent a >3x improvement relative to today’s state-of-the-art (SoA) lithium-ion battery (LiB) solutions, and which may be necessary for electrifying the sectors of interest identified in this RFI. As the constraints of classical energy storage thinking are reconsidered, operating temperature, fuels versus oxidizers and the physical boundaries of the energy storage system are all up for grabs. Think less “out of the box”, and more that there is no box.


Respondents shall not include any information in their response to this RFI that might be considered proprietary or confidential.

Responses to this RFI should be submitted in PDF format to the email address by 5:00 PM Eastern Time on Wednesday, March 8, 2023.


Submission Deadlines

  • Concept Paper Submission Deadline: TBD
  • Full Application Submission Deadline: TBD