X-ray Nano-computed Tomography of Electrochemical Conversion in Lithium-ion Battery

Herein, a nanometric CuO anode for lithium-ion batteries was investigated by combining electrochemical measurements and ex situ X-ray computed tomography (CT) at the nanoscale. The electrode reacted by conversion at about 1.2 and 2.4 V versus Li+/Li during discharge and charge, respectively, to deliver a capacity ranging from 500 mAh g−1 to over 600 mAh g−1. Three-dimensional nano-CT imaging revealed substantial reorganization of the CuO particles and precipitation of a Li+-conducting film suitable for a possible application in the battery. A lithium-ion cell, exploiting the high capacity of the conversion process, was assembled by using a high-performance LiNi0.33Co0.33Mn0.33O2 cathode reacting at 3.9 V versus Li+/Li. The cell was proposed as an energy-storage system with an average working voltage of about 2.5 V, specific capacity of 170 mAh gcathode−1, and efficiency exceeding 99 % with a very stable cycling.