Search

Abstract: The paper reports and discusses the results of electrochemical tests carried out according to the DOE Battery Test Manual for plug-in Hybrid Electric Vehicles (PHEVs) on laboratory high-voltage graphite/LiNi0.4Mn1.6O4 cells with electrode formulation and mass-loading suitable for scale-up, and mixed ethylene carbonate–dimethyl carbonate with two diverse lithium salts, lithium tris(pentafluoroethyl)trifluorophosphate and LiPF6, as electrolytes. The cells, assembled with two different separators, a polypropylene monolayer separator (Celgard®2400) and a reinforced polyvinylidene fluoride macroporous membrane (PVdF-NCC), were also tested by deep charge/discharge cycles. The results show the strong impact of the separator on high-rate cell functioning in PHEVs. [Copyright &y& Elsevier]

Graphite/LiNi0.4Mn1.6O4 cells assembled with a new reinforced polyvinylidene fluoride (pVDF)–nano crystalline cellulose (NCC) separator and EC–DMC 1 M LiFAP electrolyte with additives were tested by deep charge/discharge cycles at different C-rates and by the FreedomCAR DOE protocol to simulate the dynamic functioning of the batteries in power-assist full hybrid electric vehicles (HEVs). The results of this study evidence the beneficial impact of the pVDF–NCC macroporous membrane with respect to the polypropylene monolayer Celgard®2400 separator on the high C-rate cell performance. The deep charge/discharge of the cell with pVDF–NCC at C/1 effective rate provided 101 W h kg−1 to be compared with 85 W h kg−1 of the cell with Celgard®2400 (the cell weight was considered twice the composite electrode weight of both electrodes). Also hybrid pulse power characterization tests based on the FreedomCAR protocol at 5 C and 10 C demonstrated the superior performance of the cells with pVDF–NCC with respect to that of the cells with Celgard®2400 even if both cells exceed the FreedomCAR goals of power and energy for minimum and maximum power-assist HEV. [ABSTRACT FROM AUTHOR]

Abstract: The performance of full cells featuring high-voltage LiNi0.4Mn1.6O4 cathode and graphite anode with carbonate-based electrolytes, ethylene carbonate (EC) -dimethyl carbonate (DMC) with conventional LiPF6 and non-conventional Li[(C2F5)3PF3] (LiFAP) lithium salts with and without SEI-forming additives 1-fluoro ethylene carbonate (F1EC) and succinic anhydride (SA) is investigated. The results evidence the beneficial impact of EC-DMC-1M LiFAP electrolyte (LF30), with respect to EC-DMC-1M LiPF6 electrolyte (LP30), also in presence of 1.6% F1EC-2% SA additives, on charge retention over cycling and on self-discharge of full cells. After the 25 cycles of the charge capability test, the charge retention reached values up to 70% with LF30 and 87% with LF30 and additives, and fully charged cells with LF30-additives delivered 53% of the stored charge after one week in OCV. [Copyright &y& Elsevier]

In the past 10-15 years, the microbial fuel cell (MFC) technology has captured the attention of the scientific community for the possibility of transforming organic waste directly into electricity through microbially catalyzed anodic, and microbial/enzymatic/abiotic cathodic electrochemical reactions. In this review, several aspects of the technology are considered. Firstly, a brief history of abiotic to biological fuel cells and subsequently, microbial fuel cells is presented. Secondly, the development of the concept of microbial fuel cell into a wider range of derivative technologies, called bioelectrochemical systems, is described introducing briefly microbial electrolysis cells, microbial desalination cells and microbial electrosynthesis cells. The focus is then shifted to electroactive biofilms and electron transfer mechanisms involved with solid electrodes. Carbonaceous and metallic anode materials are then introduced, followed by an explanation of the electro catalysis of the oxygen reduction reaction and its behavior in neutral media, from recent studies. Cathode catalysts based on carbonaceous, platinum-group metal and platinum-group-metal-free materials are presented, along with membrane materials with a view to future directions. Finally, microbial fuel cell practical implementation, through the utilization of energy output for practical applications, is described.