Expeditionary Technology Search (xTechSearch) Dual-Use Technologies to Solve Challenging Army Problems
Abstract
In this project, Eonix proposed the development of a carbonate-free, non-flammable electrolyte to enable the realization of a safer, more stable lithium-ion battery for the Next Generation Combat Vehicle (NGCV). The proposed electrolyte paired a well-known high stability, non-flammable solvent (sulfolane) with a suite of passive and active additives developed by Eonix to address the low temperature and conductivity deficiencies of this solvent, sulfolane, as well as the inability to form a stable solid electrolyte interphase layer. Eonix was tasked with designing an electrolyte with these non-flammable components that matches or exceeds the performance of the MIL-PERF-32565 energy storage unit (72 Wh/kg, Cycle Life 1000, Charge Rate 1C, Discharge Rate 2C) and demonstrating this improvement in a multilayered pouch cell with a graphite anode and NMC532 cathode. To accomplish this research project, Eonix had two technical tasks with subtasks. The first technical task expected Eonix to design an electrolyte using 5mAh benchtop cells, with an embedded reference electrode for monitoring half-cell potentials, by adjusting passive and active additive concentrations and then designing formation cycles to properly initiate the generation of a stable solid electrolyte interphase. The first subtask focused on the concentration adjustments that resulted in the greatest capacity retention for the cells. The second subtask focused on evaluating the differential capacity peaks to determine the optimal formation protocol that would properly stabilize the anode for reversible cycling of the device in the absence of a carbonate electrolyte. The conclusion of the first technical task was a candidate electrolyte that would meet or exceed the MIL-PERF32565 performance metrics while using a solvent with a high flashpoint. This task was completed on December 10th, 2020. The second technical task expected Eonix to fabricate pouch cells with the candidate electrolyte from the first task.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 28, 2021
- Accession Number
- AD1141146
Entities
People
- Donald Derosa