L3Harris Technologies and the U.S. Navy have integrated fault-tolerant Lithium-ion Passive Propagation Resistant (Li-ion PPR) battery technology into the Iver4 900 Autonomous Underwater Vehicles (AUVs).
Inspired by NASA’s spacesuit power systems, these advanced batteries mark a significant leap forward in unmanned underwater operations, offering twice the endurance of earlier single-use battery systems. The innovation is a cornerstone in enhancing the operational capabilities of the Torpedo Tube Launched and Recovered (TTL&R) Iver4 900 AUVs.
The delivery of the first production AUVs, announced in a press release by L3Harris on November 12, 2024, underlines the Navy’s commitment to integrating cutting-edge unmanned technologies into its submarine fleet.
Developed by Inventus Power, the Li-ion PPR batteries leverage a modified version of L3Harris’ Battery Management System (BMS) to ensure safe and efficient energy management. Unlike traditional batteries, the PPR design minimizes the risk of thermal runaway—a critical safety consideration for military-grade equipment. This innovation has already received approval from the Navy Weapon Systems Explosives Safety Review Board (WSESRB), underscoring its reliability in demanding naval applications.
Li-ion technology has long been hailed for its superior energy density, longevity, and stability, making it the go-to solution for high-performance devices. For the Iver4 900 AUVs.
- Twice the Endurance: Rechargeable power doubles mission duration compared to earlier single-use batteries.
- Extended Lifespan: An operational life of 8-10 years, outlasting the 3-5 years typical of other battery systems.
- Efficiency in Logistics: Reduced resupply demands allow for multiple sorties with minimal logistical impact.
- These attributes maximize operational readiness, ensuring the Iver4 900 AUVs are primed for the Navy’s complex and covert missions.
One of the most compelling capabilities of the Iver4 900 AUVs is their ability to be launched and recovered into submarines while underway. This feature provides a critical tactical advantage, enabling host submarines to maintain stealth while deploying unmanned systems for reconnaissance, surveillance, and other mission-critical tasks. The compact design and rechargeable battery technology also preserve a submarine’s limited onboard ordnance capacity.
“This innovation aligns perfectly with the Navy’s focus on unmanned platforms and distributed maritime operations,” said Dan Packer, AUKUS Director for the Navy’s Submarine Force. “By reducing the footprint of batteries and extending mission capabilities, these systems enable submarines to conduct covert operations without compromising ordnance capacity or maneuverability.”
The data collected by the AUVs is vital for navigational planning and decision-making, further advancing manned-unmanned teaming operations. With high-fidelity imaging and real-time data transfer, the Iver4 900 enhances situational awareness in contested waters.
In 2023, L3Harris demonstrated the first fully autonomous, repeatable launch and recovery of an AUV from an underway submarine—a pivotal step in the development of hybrid operational concepts. This achievement represents a seamless blend of manned and unmanned systems, positioning the Navy to address the evolving challenges of modern maritime threats.
The success of these trials validated the integration of rechargeable Li-ion PPR batteries, proving their resilience and adaptability in operational environments. The resulting hybrid operational model not only strengthens mission flexibility but also aligns with the Navy’s broader Distributed Maritime Operations (DMO) strategy, which emphasizes the deployment of dispersed, networked platforms.
The Iver4 900 AUV is a state-of-the-art unmanned vehicle designed for an array of commercial and defense applications. From long-range oceanographic surveys to anti-submarine warfare and mine countermeasures, the AUV is tailored for the most demanding missions.
- Construction: Built with titanium and carbon fiber for durability and corrosion resistance.
- Dimensions: Measures 2.5 meters in length and 9 inches in diameter, allowing operations at depths of up to 300 meters.
- Propulsion: Equipped with a brushless DC motor and a three-blade stainless steel propeller, capable of transit speeds over 3 knots and sprint speeds exceeding 5 knots.
- Surface: GPS with WAAS correction ensures precise positioning.
- Subsurface: A Nortek Doppler Velocity Log (DVL) combined with an iXBlue PHINS Compact C3 fiber-optic gyroscope ensures accurate subsurface navigation.
These advanced features enable the Iver4 900 to operate with unparalleled autonomy and precision, even in challenging environments.
The integration of Li-ion PPR battery technology into the Iver4 900 AUV represents more than a technological upgrade—it is a strategic shift in naval warfare. By equipping submarines with advanced unmanned capabilities.
- Conduct covert surveillance without exposing manned assets to risk.
- Perform reconnaissance missions in contested or denied areas.
- Expand the operational reach of traditional platforms through unmanned systems.
The rechargeable batteries also support the Navy’s broader goals of reducing its environmental footprint and increasing the sustainability of its operations.
Dan Packer emphasized that “the partnership between L3Harris and the Navy is setting new standards for the integration of unmanned systems into traditional submarine missions, ensuring the U.S. remains at the forefront of undersea warfare.”
The delivery of Li-ion PPR battery-powered Iver4 900 AUVs aligns with the U.S. Navy’s emphasis on maintaining technological superiority in the underwater domain. As maritime challenges become more complex, the need for resilient, adaptable, and scalable solutions has never been greater.
The adoption of such cutting-edge technologies also positions the U.S. Navy as a global leader in unmanned systems innovation, setting a benchmark for allied nations. The scalable nature of these batteries ensures their potential application across other platforms, including unmanned surface vehicles (USVs) and aerial drones, further expanding their strategic utility.
Additionally, the alignment with the AUKUS partnership—focused on fostering security and technological collaboration among the U.S., U.K., and Australia—highlights the role of autonomous systems in strengthening allied maritime operations.
The integration of Li-ion PPR battery technology into the Iver4 900 AUVs is a landmark achievement for both L3Harris and the U.S. Navy. This innovation not only enhances the endurance and versatility of unmanned underwater vehicles but also reinforces the Navy’s commitment to staying ahead in an increasingly competitive maritime domain.
As the U.S. Navy continues to prioritize unmanned platforms and distributed operations, the collaboration with L3Harris exemplifies the potential of public-private partnerships in driving technological advancements. The Iver4 900, with its cutting-edge battery system, stands as a testament to the future of undersea warfare—where manned and unmanned systems operate in tandem to secure strategic advantages in the world’s oceans.
