Ni/NiO Based 3D Core-Shell Foam Anode for Lithium Ion Batteries

Highlights: • Ni/NiO anodes are processed by electrodeposition NiO from ionic liquids • Annealed Ni/NiO-electrode provides enhanced specific capacity and stable cyclability • NiO sub-layer, formed by thermal oxidation, is the main origin of capacity increase • Electrochemical performance of Ni/NiO anodes was evaluated in half and full cells - Abstract: An innovative route to obtain Ni/NiO core-shell foam-based anodes for lithium-ion batteries is presented. Commercial Ni foams are conformally coated with NiO by ionic liquid-based electrodeposition. The electrochemical behavior of the resulting Ni/NiO electrodes in half coin cells with lithium counter electrode is investigated. The results are qualitatively correlated to the microstructural properties, including effects of the thermal annealing at 500 °C, of the NiO shell. The formation a NiO sub-layer by the thermal oxidation of the Ni foam seems to play a crucial role in the enhanced performance of the annealed Ni/NiO anodes, which exhibit a reversible discharge capacity around 0.8 mAh/cm². Furthermore, the Ni/NiO core-shell foam-based anodes are evaluated in full coin Li-ion cells with high voltage LiMn_0.8Fe_0.2PO₄ cathode. Promising cyclability is reached in NiO-LMFP coin cells under cycling at 0.4C.