화학공학소재연구정보센터
Journal of Power Sources, Vol.166, No.1, 273-283, 2007
Reserve, thin form-factor, hypochlorite-based cells for powering portable systems: Manufacture (including MEMS processes), performance and characterization
This work focuses on fabrication routes and performance evaluation of thin form-factors, reserve cells, as a powering alternative for expendable and/or remotely operated systems. The catalytic decomposition of sodium hypochlorite solutions is revisited herein with two cost-effective anodes: zinc and aluminum. Aluminum, even though the most expensive of the utilized anodes, constituted cells with double the energy content (up to 55 Wh kg(-1)) than those fabricated with zinc. Even though the hypochlorite concentration in the solution limits the cells' operational life, attractive performances (1.0V with a current of 10mA) for the manufactured cells are obtained. It is shown that micro fabrication processes, allowing for close electrodes interspacing, provided high faradic and columbic efficiencies of up to 70 and 100%, respectively. Obtained specific energies (50-120Wh kg(-1)) are in the same order of magnitude than batteries currently used for powering deployable systems. Experimental results show that a simple model that linearly relates over potentials and the electrical load, adequately describe all the cell designs. A mathematical model based on a kinetic-mechanistic scheme that relates the current output as a function of time agrees fairly well with results obtained activating cells with various concentrations of NaOCl solutions. (c) 2007 Elsevier B.V. All rights reserved.