Batteries are often in the public discourse as an important weapon in our fight against climate change because they can store large amounts of energy in a modular and portable manner. Because of the intermittency of renewable energy technologies such as solar and wind, there has been fervent research in the hunt for high energy density (energy stored per mass) and longer-lasting batteries. However, current lithium-ion batteries are expensive and lack the required energy density to truly enable a new electrified energy economy. In contrast, lithium metal batteries have an order-of-magnitude higher energy density, but are plagued by the high reactivity of lithium, and the lack of stable electrolytes (ionically conductive media). In this talk, I will discuss in depth how batteries work, state-of-the-art challenges, and my research groups’ work on developing new electrolytes for lithium metal batteries. Finally, I will discuss new approaches such as data science that are of interest for novel battery electrolyte design.