This paper investigates the potential use of a network of distributed battery storage systems to provide flexibility in the form of imbalance energy to a balancing group (BG). A methodology to calculate the flexibility potential of such a network is introduced and applied to a simulated battery storage network (BSN) consisting of 89 storage units. Moreover, a conceptualization including several alternatives of a decentralized optimization framework for electricity balancing groups that efficiently utilize energy storage systems, together with a brief overview of potential implementation technologies, is proposed.