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Despite considerable progress of silicon/carbon (Si/C) composites anodes, they still suffer from high irreversible capacity losses, which are mainly due to continuous Solid Electrolyte Interphase (SEI) layer formation, which consumes a large amount of lithium. To compensate for the active lithium losses, prelithiation of Si-based anodes has been attempted. In this manuscript, we report the effect of prelithiation on Si/C anodes combined with LiNi 0.5 Mn 0.3 Co 0.2 O 2 cathodes in full cell configurations. To prepare Li x Si/C anodes, Si/C electrodes were lithiated electrochemically at 0.1 and 0.5 V vs. Li/Li + in half cell configuration before assembly of the full cell. Special attention is paid to the effect of the degree of prelithiation on initial electrochemical behavior and Li dendrite formation. In this work, electrochemical investigations were performed by using two-electrode and three-electrode measurements. Furthermore, the morphology of the active materials before and after cycling were characterized by post mortem Scanning Electron Microscopy (SEM).

As the automotive industry shifts from internal combustion engine (ICE) vehicles to electric vehicles (EVs), many countries are setting new strategies in their transportation sector. The Li-ion battery is currently the most common battery used in EVs due to its high energy density, durability, safety, and cost competitiveness. Nickel is predicted to be an essential component for the lithium nickel cobalt manganese oxide (NMC) as a cathode material of choice for EV applications. Indonesia, one of the world’s largest nickel ore suppliers, put an export ban on nickel ore effective from 2020. The bold movement was intended to initiate the domestic EV industry and encourage investors abroad to drive their manufacturing activities into the country. On the other hand, the global Li-ion battery manufacturers who imported nickel from Indonesia had to restrategize their businesses. This review discussed the chronological events leading to the ban and after the ban from the media, government regulations, and literature reviews. The authors of this study also conducted interviews and attended seminars with the national experts and key players in the battery and EV industry to gain their most pertinent insights. The SWOT analysis of the reviewed materials indicated that while the Indonesian battery industry is still new, it needs to diversify its research and development activities and collaborate internationally to optimize the utilization of its resources and meet the purchasing power of the domestic EV market. Finally, this study summarized six key factors to support Indonesia’s ambition to be a new regional hub for EVs. These factors are: (1) pricing, (2) technology, (3) policy, (4) investment, (5) infrastructure, and (6) compliance with sustainability standards.

Silicon is a promising candidate for anodes in lithium-ion batteries (LIB) due to its high theoretical capacity. However, Si has low electrical conductivity (theoretical: 6.7 x 10 -4 S cm -1 ). Proper conductive additive is needed in order to improve the electrical conductivity of Si-based anodes. Here we focus on applying two commercial conductive addictives: graphite and carbon black Super C65 for silicon-mesoporous carbon (Si/MC) composite anodes. The structure and morphology of the electrodes were characterized by nitrogen adsorption, scanning electron microscopy (SEM), and focus ion beam/transmission electron microscopy (FIB/TEM). Furthermore, the electrochemical performance of the electrodes was characterized by cyclic voltammetry, galvanostatic charge/discharge tests, and impedance spectroscopy. In principles, our work could be effective for the choice of conductive additives to improve the electrical performance of Si/MC anodes.

Coating conducting polymers onto active cathode materials has been proven to mitigate issues at high current densities stemming from the limited conducting abilities of the metal-oxides. In the present study, a carbon coating was applied onto nickel-rich NMC622 via polymerisation of furfuryl alcohol, followed by calcination, for the first time. The formation of a uniform amorphous carbon layer was observed with scanning- and transmission-electron microscopy (SEM and TEM) and X-ray photoelectron spectroscopy (XPS). The stability of the coated active material was confirmed and the electrochemical behaviour as well as the cycling stability was evaluated. The impact of the heat treatment on the electrochemical performance was studied systematically and was shown to improve cycling and high current performance alike. In-depth investigations of polymer coated samples show that the improved performance can be correlated with the calcination temperatures. In particular, a heat treatment at 400 °C leads to enhanced reversibility and capacity retention even after 400 cycles. At 10C, the discharge capacity for carbon coated NMC increases by nearly 50% compared to uncoated samples. This study clearly shows for the first time the synergetic effects of a furfuryl polymer coating and subsequent calcination leading to improved electrochemical performance of nickel-rich NMC622.

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In this work, the effect of Cr3+ partial substitution on vanadium site in monoclinic lithium vanadium(III) phosphate (LVP) structure resulting in compounds with general formula: Li3V2- xCr x(PO4)3-C ( x = 0, 0.05, 0.1, 0.15) was studied. A two-step sol-gel combustion method was employed in syntheses. The samples were characterized by X-ray powder diffraction, scanning electron microscopy, coupled plasma optical emission spectroscopy, and flash combustion. The electrochemical performance of the active materials was examined through rate capability tests and cyclic voltammetry. The unsubstituted compound LVPC delivers higher capacity compared to the Cr-containing samples due to chromium inactivity in the potential range 3.0–4.4 V vs. Li/Li+. However, the Cr-substituted materials show better overall capacity retention (97–97.6%) in contrast to Li3V2(PO4)3-C (96%) in long cycling.

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