Design of safe lithium ion batteries require innovations in materials for cathodes, anodes, and electrolytes. In particular, the role of 2D materials can be significant to boost safety. This presentation provides an overview on the efforts in the PI's lab to design thermally safe high energy density batteries. At first, I will show how the thermal stability of cathodes can be improved by encapsulation of electrode particles within graphene materials. Then, I will discuss how 2D materials can make the solid electrolytes to cycle better in Li-metal batteries. At the end, I will show the effect of graphene oxide coating on glass fiber separators as a novel means to combat lithium dendrites.