| Overcoming the Technical Barriers that Inhibit use of Fuel Cells for Dismounted Soldier Applications|
|Sensors & Electronics Technology|
Battery Charging, Dismounted Soldier, Fuel Cells, Portable
The evolution of warfare over the last two decades has demonstrated the increased reliance on electronics for the dismounted warfighter to be able to successfully complete his mission. These applications fall into two general categories, manwearable (such as radios, GPS, small computers) and manportable (small unmanned vehicles, IED defeat devices, laser rangefinders). Regardless of the actual application, the dismounted soldier must not only carry the various devices but also sufficient energy to power these devices for the length of the mission. For the vast majority of these devices the energy required is provided by some form of rechargeable lithium ion battery pack, which is life cycle cost effect but requires some form of recharging support to enable the completion of the mission. The result is that mission objectives, planning and execution is partially driven by the run time of batteries and the associated increase in weight carried and logistically resupply issues. All of this has a negative impact on the goal of allowing the dismounted soldier to complete the mission without energy resupply, or to become “energy independent”.
Several energy solutions have been explored to provide this energy independence. Nonrechargeable batteries offer the longest mission times, lightest weight and simplest logistics, but the unit price for military unique technologies/configurations make them cost prohibitive. Solar panels work well in the desert and in static locations, but not where there are obstructions or in a mobile environment. Kinetic energy devices are another area, but have yet to prove the ability to generate enough energy to compensate for the additional weight to be carried. Fuel cells were considered a viable option, but past efforts were hindered by SWaP tradeoffs, low reliability and high unit costs. However, recent advances in fuel cell technologies are starting to make this technology once again attractive for use in a tactical environment.
When combined as a hybrid solution with rechargeable batteries, fuel cells have the potential to eliminate the logistics associated with battery charging by providing an in situ recharging capability. This eliminates the need for separate battery chargers and allows for extended mission times without having to replace batteries.
Many NATO counties have adapted, or are moving towards the concept of the dismounted soldier as a system, whereas all the electronics carried are interconnected and powered by a single energy source. Use of a fuel cell acting as a battery charger eliminates the need to replace each individual battery when depleted.
This effort will leverage the work of previous SET Technical Groups, specifically SET 173 “Fuel Cells and other Emerging Manportable Power Technologies for the NATO Warfighter” and SET 206 “Energy Generation for Manwearable/Manportable Applications and Remote Sensors”. SET 173 studied the utilization of fuel cells in various systems where SET 206 studied dismounted soldier systems and the impact of various energy sources. The overall objective of this panel would be to identify the technical challenges related to the use of fuel cells for dismounted applications and recommend a roadmap for corrective actions. Specific goals would be too:
• Identify those fuel cell technologies and configurations that are applicable to either manwearable or manportable applications
• Determine the technical barriers that exist preventing full adaptation of each potential technology
• Identify methods in which the size and weight of each system can be reduced while increasing the energy output
• Identify methods by which hydrogen can be provided with minimal logistics impact
• Identify the efforts required to overcome defined technical barriers
• Make recommendations as to where nations can leverage resources
• Recommend standardization and specification protocol
• Serve as subject matter experts and act as a liaison to other NATO technical teams
It is expected that the TRL of the proposed technologies will be a 4-6 at the conclusion of the study,
No CDT is projected.
The specific topics to be covered are:
• Fuel Cells - Identification and proposed technical solutions related to decreasing weight, increasing energy output and increasing reliability. One of the major focuses will be on trying to identify reasons for failures of fuel cells in a battle field environment and development of military specific mitigation concepts.
• Hydrogen generation and delivery systems – Identify and propose potential “non-traditional” sources of hydrogen generation such as the use of windshield washer fluids, F-54 diesel /F-34 jet fuel, hydrogenated diesel or jet fuels, liquid organic hydrogen carriers and chemical hydrides.
• Safety – Identify and propose solutions to allow the use of fuel cells in closed environments such as aircraft and tactical vehicles. Analyze emission from different fuel cell types including parasitic emissions e.g. of fuel transfer line also allowing for data from aged systems as far as they become available. Evaluate options to contain emissions, and define required ventilations of confined rooms also taking into account oxygen conception so that emissions by soldiers can be kept at a safe level
• Hybrid solutions – Explore exploiting the occurrence of variable loads by optimizing energy and power delivery from the system through combining the fuel cell with an electrochemical storage device such as a high power battery, a ultra-capacity or a battery capacity hybrid solution
• Battery charging – Explore the methods by which a fuel cell can directly, or in directly, operate as a battery charger in a tactical environment.
• Specifications and standards required to leverage resources and enable NATO interchangeability