So far, various approaches have been presented to overcome this issue, including different metal ion doping , surface treatment with conductive materials , synthesis of nanomaterials , and partial reduction of surface Ti4+ to Ti3+ by hydrogen . However, most of methods are considered complicated and expensive processes in the aspect of a large scale production.
In this work, we fabricate various Li4Ti5O12 materials with different Ti3+ content through a carbothermal reduction process and intensively investigate the effect of Ti3+ on their electrochemical performances. In addition, we suggest an optimal surface composition of Li4Ti5O12 materials enabling high current operation as well as high capacity.
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