Thin, flexible all-solid-state batteries

The miniaturisation of connected electronics is exposing fundamental limitations of conventional liquid-electrolyte lithium-ion batteries. While these cells offer high energy density, they often struggle to deliver sufficient power density, requiring additional components such as capacitors or oversized batteries to meet peak power demands. In addition, their reliance on flammable liquid electrolytes imposes constraints on form factor, safety, and operating temperature range. As devices become thinner, more integrated, and increasingly deployed in harsh environments, alternative battery architectures are required.

This talk introduces thin-film solid-state lithium battery technology as a pathway to overcome these limitations. It reviews the core principles of solid-state thin-film cells, with a focus on electrochemical design, manufacturing methods, and the challenges of scaling beyond laboratory demonstrators. Drawing on production concepts adapted from semiconductor and vacuum-deposition industries, the talk outlines approaches for continuous, roll-to-roll fabrication of ultra-thin battery foils. Finally, device-level performance is connected to emerging application requirements in wireless sensors, smart labels, and compact wearables, illustrating how solid-state thin-film batteries enable new classes of electronics that are fast-charging, intrinsically safe, and compatible with extreme operating conditions.