Energy density and cost of Li-ion batteries (LIBs) based on conventional intercalation compounds are closely approaching their limits. The reliance of conventional cathodes on the use of toxic metals additionally endangers health and safety of miners in developing countries. Conversion-type active materials offer an opportunity to double energy stored in LIBs, reduce their cost by the same factor, and improve cell safety. These materials may be produced from safer, cheaper and globally available resources and contribute to accelerated adoption of electric transportation. Formation of effective nanocomposites is likely a necessity for the successful commercialization of conversion-type electrodes, including silicon (Si) - based anodes, lithium sulfide (Li2S) and metal fluoride - based cathodes. I will discuss approaches taken by our laboratory to address current challenges of such materials.