The Effect of Carbon Starting Material on Li/CFx Batteries with Graphene Paper As Flexible Current Collector

Abstract

Li/CFx batteries are known to have the highest theoretical specific capacity in comparison to other primary lithium batteries, which are commonly used for many applications such as emergency power source, cameras, memory back-up, electronic counter, electrical lock, electronic measurement equipment, military and implantable medical devices. However, the low electrical conductivity of CFx limits the development of Li/CFx batteries where high power density is needed. Graphene paper has been developed as flexible current collector to improve the power density of Li/CFx batteries. As known the importance of carbon starting materials, recently, three different types of carbon(coke, mesoporous carbon and graphite) have been fluorinated and developed, in order to promote some particular electrochemical parameters, namely the power density, the discharge potential, or the energy density. Overall, the carbon fluorides with graphite as precursors present no voltage delay at the beginning of discharge and excellent electrochemical properties at high current density. The carbon fluorides with mesoporous carbon as precursors own the highest discharge potential. While, carbon fluorides with coke as precursors deliver the highest energy density(810 mAh/g). As the result shown, carbon starting materials strongly influence the electrochemical performances of Li/CFx batteries. It is necessary and significant to choose precursors and design the battery system according to varied applications. The main part of this work was supported by National Nature Science Foundation of China (No.21373137) and Shanghai Municipal Science and Technology Commission (No.15DZ2282000 and No.14JC1491800). Figure 1