Scalable and De-centralized Battery Management System for Parallel Operation of Multiple Battery Packs

Large-scale energy storage applications require multiple lithium-ion battery packs operating in parallel. Such applications comprise of renewable energy storage systems, battery packs for large-scale automobiles such as electric trucks, tanks, armoured vehicles, diesel-electric submarines, etc. The current technology to enable parallel operation of multiple battery packs is quite hardware intensive. It requires a separate pack management system operating as a master and battery management systems in each of the battery packs configured as slaves. This significantly affects the scalability of such systems as the number of battery packs that can be connected in parallel is completely dependent on the capacity of the master. This paper presents an alternative approach through a decentralized pack management system. The proposed approach does not require the master-slave configuration of battery packs and does not require any centralised hardware to manage the battery packs. Instead, this methodology enables the individual battery packs to communicate with each other independently thereby enabling decentralised pack management. Thus, there is no theoretical limit to the number of packs that can be operated in parallel and this allows the system to he capable of scaling up to meet virtually any size, small, medium or large.