The invention provides an energy storage system having storage elements linked for collective charging and discharging. Monitoring circuitry is provided for monitoring each of the storage elements independently. Preferably, the system includes control circuitry configured for controlling the linking of individual storage elements in order to enhance system performance. In preferred embodiments, the system also includes storage elements in an arrangement whereby they may be selectably linked and delinked, in series, parallel, or in one or more series/parallel combination.