Enhanced cycle stability of hybrid Li–air batteries with carbon nanofiber grown on carbon black

Abstract

The use of advanced carbon materials as an air electrode in hybrid Li–air batteries was thought to improve electrochemical performances such as cycle stability and a low voltage gap between discharge and charge. In this study, a carbon nanofiber grown on carbon black (CNF–CB) was prepared by a chemical vapor deposition (CVD) method at different temperatures (640–840 °C), and the electrochemical performance of the hybrid Li–air batteries based on the CNF–CB electrodes was investigated. The Li–air cell based on CNF–CB 740, with a cut-off voltage in the range of 2.5–4.2 V at 0.5 mA cm⁻² showed good cycle stability and demonstrated about 75 cycles (about 300 h) without an obvious increase in charge voltage.