TECHNOLOGY AREA(S): Human Systems
OBJECTIVE: Develop a ballistic-resistant replacement for the conformal wearable battery, based on shear thickening electrolyte, capable of replacing/supplementing soft armor and providing high quality power for Battlefield Airmen wearable electronic equipment.
DESCRIPTION: Battlefield Airmen are heavy utilizers of electronic information and communication equipment. The typical batteries (BA-5590, BB-2590) used to power this equipment are a significant limiting factor in battlefield airman operations. The size, shape and weight of these batteries are ergonomically undesirable which prompted the development of low profile, conformal batteries that can slip into the body armor carriers and tactical vests. Unfortunately the thickness of the conformal battery required to support Battlefield Airman power usage creates compatibility issues with the soft armor and hard armor plates needed to provide small arms and shrapnel protection. If the conformal battery could be improved to provide equivalent ballistic protection to current soft armor a significant amount of weight and bulk could be eliminated from the tactical vest resulting in improved fit, mobility and comfort. One method for providing this ballistic protection would be to encase the battery cells in a ballistic material cover. Swapping the thin non-ballistic cover for a ballistic cover would provide a small amount of space and weight savings, but to achieve significant ergonomic improvement other material changes must be explored. A major portion of battery volume is comprised of electrolyte. Recent research has shown that a shear thickening electrolyte could be sufficiently fluid to maintain good conductivity under normal conditions, yet provide significant shear resistance during the rapid application of ballistic force. Not only would the shear thickening electrolyte in a wearable battery reduce the risk of penetration and energy transmission of small arms rounds to the operator; it could also reduce the risk of electrode contact during battery cell perforation and deformation which can result in fire and serious burn hazards. The battery must be rechargeable, ideally with a BB-2590 charger with high performance (200Wh/kg) while conforming to the SAPI pockets used by battlefield airmen without customization. It should have sufficient performance over a wide temperature range (-30 degrees C to 60 degrees C) and humidity conditions (0 to 100%). It must have the same connectors as the BB-2590 and have similar storage capacity. Ballistic protection should be National Institutes of Justice (NIJ) type 2 or equivalent. The multifunctional capability of a shear thickening electrolyte should provide substantial improvement in space, weight, ergonomics and safety of wearable power and armor systems.
PHASE I: Design and define performance parameters/integration constraints for the battery. Demonstrate feasibility of a shear thickening electrolyte providing ballistic protect. Demonstrate sufficient fail-safe capabilities, safe and reliable charge/discharge capabilities, performance in various temperature and humidity conditions, structural robustness, and energy/power efficiency to meet design metrics.
PHASE II: Produce a prototype battery and perform ballistics testing. Provide a demonstration battery to the government for analysis. Optimize the technology for weight, volume, integration into SAPI pockets, reliability and ruggedization supporting the specified environmental conditions. Develop test plan and conduct laboratory testing to confirm performance. Demonstrate and validate the ability to meet required performance and safety metrics. Conduct a formal risk assessment, and document key program risks.
PHASE III: Produce production representative articles for operational test. Submit production representative articles for NIJ and military ballistic certification. Provide operator and maintainer manuals. Develop cost and schedule estimates for full rate production.
1: Ding, D. et al., "Smart Multifunctional Fluids for Lithium Ion Batteries: Enhanced Rate Performance and Intrinsic Mechanical Protection," Scientific Reports 3, Article Number: 2485 (2013). http://www.nature.com/articles/srep02485#ref-link-section-57
2: U.S. Department of Justice. Ballistic Resistance of Body Armor, NIJ Standard-0100
3: AFSC 1C2X1 Combat Control Career Field Education and Training Plan. http://static.e-publishing.af.mil/production/1/af_a3_5/publication/cfetp1c2x1/cfetp1c2xpdf
4: Ding, D., "Toughening up Batteries from the Inside Out," Australian Government Department of Defense, 26 October 201 http://www.dst.defence.gov.au/news/2016/10/26/toughening-batteries-inside-out
KEYWORDS: Electrolyte, Shear Thickening, Ballistic Protection, Battery, Rechargeable, Battlefield Airman