Lithium/organic and lithium/sulfur batteries have attracted great interest lately due to their high theoretical specific capacity and potential low cost. However, two major roadblocks currently prevent industrial development of these kind of batteries: (i) the progressive dissolution of active material in the electrolyte which hinders cyclability of the devices and; (ii) the electrical insulating nature of organic or sulfur materials. In this work, we show an elegant solution to solve both, the conductivity and dissolution issues. We covalently functionalized multi‐walled carbon nanotubes (MWNTs) with electrochemically active thiolated molecules. The MWNTs insure a well distributed electronic conductivity inside the positive electrode and serve as a support for a covalent immobilization of the thiolated active species. Compared to electrodes formed by simply mixing carbon nanotubes with thiol‐containing molecules, covalently functionalized MWNT materials present an excellent stability over prolonged cycling and a promising specific capacity, in the range of 100 mAh gelectrode−1, i. e., including carbon and current collector masses.