West Bethesda, Md. –
The U.S. Navy, as well as the entirety of the armed services, has long had prodigious energy needs; with the rise of critical new technologies, that demand for power and energy is growing exponentially. Lithium-I on batteries have become the enabling technology to address these power and energy demands to support surface, undersea, air, and ground requirements. Because of the inherent risks of lithium batteries—they can be both a fire and explosion hazard if handled improperly—containment strategies are critical to their successful deployment. Container solutions supply both a transportation and storage functionality, as well as provide risk reduction in the event of a battery casualty. For the last several years, Naval Surface Warfare Center Carderock Division has tested commercial- and government-designed container solutions and developed different container storage methods to reduce platform risk associated with the transportation of lithium-ion batteries.
“A safe means to transport, store, and charge lithium-ion batteries is critical for preventing catastrophic failure, and to enhance operational readiness for the warfighter,” said Jessica Schwartz, a chemical engineer in Carderock’s Battery Certification and Integration Branch.
While becoming increasingly more popular, battery containment methods are not a new concept. More than a decade ago, battery testing evaluated the heat and gas released from high energy dense lithium batteries intended to be transported on amphibious assault ships. These data were used in the development of the Lithium Battery Facility, which was designed with specially designed lockers and ventilation and fire suppression systems for the compartment. The work done in support of the facility’s development has informed later container designs.
The MK-18 Mod 2 unmanned underwater vehicle MILVAN (a modified shipping container, similar to the one above) is the Navy’s first large container system, designed by the Army’s Prototype Integration Facility. It weighs 13,000 pounds and has a dual purpose as a mitigation containment unit and general workspace. It holds two MK-18s, sitting on top of two workbenches. It has been deployed since 2013 with no issues reported. The MILVAN was designed with a fire detection and actuation system with dual-trigger smoke and heat detectors, gas extraction systems, and water suppression, including fire suppression and ventilation.
The Prototype Integration Facility also designed the Knifefish Support Container, which holds 42 Knifefish unmanned underwater vehicle batteries inside 42 lockers and is an environmentally controlled workspace for charging and discharging. The container also is equipped with dual-trigger smoke and heat detectors, gas extraction systems, and water suppression. Testing demonstrated that a battery casualty could be contained to a single locker.
Currently, Carderock Division has evaluated more than 10 government designed container options and three commercial options. The division's Battery Certification and Integration Branch has designed two container solutions. One is the Charging-capable Lithium-ion Autonomous Safe Storage Interservice Container (CLASSIC).
A large part in Carderock’s container approach was not getting too complicated with the design, but instead focusing more on predicting when a battery will fail.
The CLASSIC is a 2,000-pound container that was created in response to an Army request to transport aggregated small lithium-ion battery safely by air. CLASSIC incorporates the Army’s Universal Battery Charger, sensors capable of detecting a battery casualty, active fire mitigation agent, and passive mitigation measures to prevent propagation of failure to other batteries stored within. Dr. Thomas Hays, a materials scientist in Carderock’s Expeditionary and Developmental Power and Energy Branch, led a battery burn demonstration using the CLASSIC at the Aberdeen Proving Ground in Maryland in November 2021, which showed the severity of a potential fire when batteries are not stored properly.
“In addition to being good at containing fire, the CLASSIC is robust, so it can help protect the batteries from damage,” said Hays. “The CLASSIC is good at what it does, but it is very large, so we also need some of these other containers for certain situations. The overall hope is for decision makers to see our product and decide to fund or support us in the technology transition process. Some funding agencies are more aimed towards getting products that have proven to work, so it is nice that we have been able to move into that territory with the CLASSIC.”
Another container method is the Vehicle-Transportable Aggregate Storage Container (VTAS), which is identical in mechanical architecture to the CLASSIC, with the only differences being the types of batteries that are serviced: VTAS is designed for Lithium 6Ts—the rechargeable Li-ion battery replacement of lead-acid batteries in military ground vehicle and the onboarding charging configuration.
Both containers were designed specifically for shipboard or shore use, but are not suitable for submarine deployment. One such container that has been designed, but not tested, by the Navy is the Coacting High Integrity Material Energetic Release Attenuation (CHIMERA) system, which was designed with six compartments for battery storage.
“The CHIMERA is a container within a container; the primary enclosures are placed in a secondary enclosure container,” said Schwartz. “It is small enough to be hand carried, and the company has demonstrated through limited testing some propagation resistance between the battery storage compartments. Our review of the company’s testing and evaluation proved that it could be a viable option for submarines.”
Currently, Carderock is starting a new project, the Department of Navy (DoN) Family of Containers.
“This is a multiphase effort that intends to develop a common standardized DoN Family of Containers systems that could be utilized at forward operating bases and aboard ships, submarines, or military aircraft,” said Schwartz. “This will reduce the reoccurring engineering costs and get critical system to the fleet faster and bring commonality to containers.”
This effort will look to address container strategies in a modular way to introduce a common set of solutions. The intention of the container design is to cover a large range of lithium batteries and capabilities. While this will not be the final lithium battery container effort in the Navy, it will provide a suite of solutions for program offices to leverage, without having to invest more money in container development than is necessary.
This story was originally published in Future Forces Magazine, Volume 9, Number 1, 2023. See link below.