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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]

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]