The amount of usable energy from a battery decreases with decrease in temperature. This impacts range and performance of an electric vehicle. In the below graph the discharge current is visualized over temperature. The desired operating temperature of a lithium-ion battery in an electric car is 15 °C to 35 °C. Below 15 °C. The implications for charging batteries are even bigger. To maximize the lifespan of lithium-ion batteries they should not be charged at temperatures below zero degrees or with very low. Does an ideal battery temperature exist? From the data in the research summarized above we can conclude it is a tradeoff between maximum usable. There are two approaches for managing battery temperature: air or liquid. Briefly we will summarize the advantages and disadvantages of the two below.