High performance 1.2 Ah Si-alloy/GraphitejLiNi0.5Mn0.3Co0.2O2 prototype Li-ion battery

The study reports on realization and electrochemical testing of prototype Si-alloy/GraphitejLiNi(0.5)Mn(0.3)Co(0.2)O(2) batteries. Water soluble polyacrylic acid (PAA), used as the only binder at the anode side, demonstrates excellent dispersant and binding properties. Sedimentation tests and rheo-logical measurements show remarkable stability and mostly a thinning behavior of the non-Newtonian type of slurry. The cathode is processed in N-Methylpyrrolidone based slurry using polyvinylidene fluoride (PVDF) as the binding agent. The electronic conductivities of the manufactured Si-alloy/Graphite and LiNi0.5Mn0.3Co0.2O2 electrodes are evaluated. Furthermore, the cathode and anode electrochemical behavior is initially studied in half-cells, and subsequently in full Li-ion stacked prototype soft pouchcells (1.22 Ah). It is demonstrated that the manufactured prototype cells can sustain about 290 charge/discharge galvanostatic cycles before the retained capacity drops below 80%. Cell aging is monitored using Electrochemical Impedance Spectroscopy (EIS), whereas post-mortem SEM analysis of electrodes cross-section is used to shed light on the causes of performance degradation of the cells. (C) 2017 Elsevier B.V. All rights reserved.