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Pawcatuck, CT, United States

Aravindan V.,Nanyang Technological University | Gnanaraj J.,Yardney Technical Products, Inc. | Lee Y.-S.,Chonnam National University | Madhavi S.,Nanyang Technological University
Chemical Reviews | Year: 2014

Apart from the mentioned applications, wind power generation, uninterruptible power sources, voltage sag compensation, photovoltaic power generation, CT and MRI scanners, and energy recovery systems in industrial machineries are worth mentioning. Carbonaceous materials are favored as EDLC components due to their high specific surface area, relatively low cost, chemical stability in solutions irrespective of the pH value, ease of synthesis protocols with tailored pore size distribution and its amphoteric nature that allows rich electrochemical properties from donor to acceptor state, and a wide range of operating temperatures. The combination reactions enable one to achieve higher energy density and specific capacitance than the EDLC counterpart. Conducting polymers and transition metal oxides are the perfect examples for pseudocapacitive materials. Source

Aravindan V.,Nanyang Technological University | Gnanaraj J.,Yardney Technical Products, Inc. | Lee Y.-S.,Chonnam National University | Madhavi S.,Nanyang Technological University
Journal of Materials Chemistry A | Year: 2013

Development of an eco-friendly, low cost and high energy density (∼700 W h kg-1) LiMnPO4 cathode material became attractive due to its high operating voltage ∼4.1 V vs. Li falling within the electrochemical stability window of conventional electrolyte solutions and offers more safety features due to the presence of a strong P-O covalent bond. The vacancy formation energy for LiMnPO4 was 0.19 eV higher than that for LiFePO4, resulting in a 10-3 times-diluted complex concentration, which represents the main difference between the kinetics in the initial stage of charging of two olivine materials. This review highlights the overview of current research activities on LiMnPO4 cathodes in both native and substituted forms along with carbon coating synthesized by various synthetic techniques. Further, carbon coated LiMnPO4 was also prepared by a solid-state approach and the obtained results are compared with previous literature values. The challenges and the need for further research to realize the full performance of LiMnPO4 cathodes are described in detail. © 2013 The Royal Society of Chemistry. Source

Agency: Department of Defense | Branch: Navy | Program: STTR | Phase: Phase I | Award Amount: 79.75K | Year: 2014

Yardney will design and develop a lightweight, safe, reliable, and cost-effective aircraft battery with improved thermal design and the use of active cooling techniques. As a novel part of the battery design, Yardney will investigate and implement high performance electrodes using three dimensional (3D) micro-porous current collectors, safer thin metal case cell design, a micro-channel heat pipe thermal control system to collect heat generated inside the battery and then conduct the heat to the outer shell, thus providing direct cooling for the overheated region. The novel design will also prevent heat propagation between the cells with a lightweight aerogel that has low thermal conductivity. Tests of the enhanced cell design will be compared with Yardney"s existing battery, which meets current full aircraft electrical performance requirements. Yardney will work with the University of Arizona, experts in thermal modeling and heat-generation studies in battery electrodes and the battery cells and investigate the most effective thermal design for the 3D electrodes and the battery pack using high performance computing systems.

A current collector including: a polymer film including a first major surface, an opposite second major surface, and a plurality of openings extending through a thickness of the polymer film; a first layer on the first major surface of the polymer film; a second layer on the second major surface of the polymer film; and a third layer on an inner surface of an opening of the plurality of openings, wherein the third layer contacts the first layer and the second layer, and wherein the first layer, the second layer, and the third layer each independently has an electrical conductivity of greater than 10 Siemens per meter.

Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 79.43K | Year: 2012

Yardney Technical Products in conjunction with Johns Hopkins University Applied Physics Laboratory is proposing to progress development of an advanced monitoring system for batteries, provide a modular battery unit, and develop a system approach to monitor and control multiple power sources and loads. Battery monitoring will be advanced via a technique to determine the internal temperature of each cell in a battery, thereby providing an opportunity to detect if a cell is approaching initiation of thermal runaway. The system will balance various parallel power sources to maintain thermal control of each by providing an opportunity to take one that is detected to be in jeopardy offline. The modular battery design will provide a unit consisting of cells and a battery management system, having advanced monitoring and control capabilities, as a standalone unit, or readily capable of arranging in a parallel and/or series configuration to meet requirements. This proposal addresses an advanced system monitoring and control approach, and a battery whose benefit is not to address"how to fail safely,"but rather how to prevent failure by detecting the anomalous behavior of a cell well before it fails.

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