High energy density of primary lithium batteries working with sub-fluorinated few walled carbon nanotubes cathode

Fluorinated carbon nanotubes used as cathode material exhibit a capacity exceeding the theoretical value when used in primary lithium battery. The measured experimental capacity, the faradic yield and the energy density were increased, exceeding the expected theoretical values for sub-fluorinated few walled carbon nanotubes (FWCNTs). Although the molar carbon/fluorine ratio was only of 0.37 (i.e CF0.37), an experimental capacity of 900 mAh.g(-1) was obtained which is higher than the theoretical value of 521 mAh.g(-1). With the same material, an unprecedented energy density of 2565 Wh kg(-1) was reached associated with a faradic yield of 172%. The materials were deeply characterized using TEM, Raman and solid state C-13 and F-19 NMR in order to explain the extra-capacity. Such high electrochemical values can be correlated to the reinforcement effect of the central tube(s), coupled with a low amount of structural defects. (C) 2017 Elsevier B.V. All rights reserved.