Paradoxically, almost every battery breakthrough seems to have an accompanying problem, and battery developers end up sometimes ditching the positive because of an overriding negative. Solid-state batteries promise some gains without compromise, though. Conventional lithium-ion batteries have possibly reached the limit of their capacity, some scientists fear, and still remain prone to issues like thermal runaway. Developers have looked at solid-state battery designs in which even the electrolyte is solid and not prone to bursting into flame. These batteries promise to have higher energy densities and longer lives, but high resistance at the electrolyte-electrode interface tends to interfere with charging and discharging speeds. Two groups of researchers at the Tokyo Institute of Technology have been taking different approaches to creating a solid-state battery with improved performance and few of the disadvantages of more conventional lithium cells. Stacking Battery Components Scientists from Tokyo Institute of Technology and Tohoku University, led by Professor Taro Hitosugi, “Fabricated all-solid-state batteries with extremely low interface …