Lithium ion devices, operated with set operative capacity

Abstract

Systems and methods are provided for operating lithium ion devices by setting an operative capacity below a rated capacity value of the lithium ion device, and operating the lithium ion device at the set operative capacity by decreasing a lower voltage cutoff value during discharging and/or by increasing an upper voltage cutoff level during charging—to support operation at the set operative capacity. The systems and methods may utilize residual lithium in device components such as anodes, cathodes, electrolyte etc. or combinations thereof, and/or external lithiation to increase the cycling lifetime of the lithium ion devices, to adapt to user preferences and expected use profiles, and to simplify device status indications to the user. Advantageously, relatively simple circuitry is required to implement the provided methods and systems, and achieve customizable operation of the lithium ion devices.