Improving the wide temperature operation of rechargeable batteries is vital to the operation of electronics in extreme environments, where systems capable of higher energy, high-rate discharge and long cycling are in short supply. In this talk, we will show electrolyte designs to achieve high-energy density and stable cycling performance in wide temperature range for both lithium-ion and lithium metal batteries. We will show how to circumvent the sluggish ion desolvation process found in typical lithium-ion batteries during discharge. These batteries are enabled by a novel ester electrolyte, which simultaneously provided high electrochemical stability and ionic conductivity at low temperature. Then we will extend the fundamental understanding developed from these system to other high-capacity, high-rate electrodes, leading to further improved energy density and stability for both high and extremely low temperatures, demonstrated by rechargeable Li metal batteries using both high-Ni oxide and sulfur cathodes.