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 LiNi0.33 Co0.33 Mn0.33 O2 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.