A 15kWh lithium battery pack has a relatively large capacity which makes it fit for storing energy that requires high demand. In domestic energy storage systems, it can store an impressive amount of solar electricity produced during the day enabling a household to draw power to meet its electricity needs throughout the day and during blackouts or during high rate times. In commercial or industrial areas, a 15kWh lithium battery pack helps in powering tools or used as standby energy. The pack utilizes modern methods of energy storage and discharge for maximum performance and long life as well as state of the art battery management systems that enable full regulation and control of the functioning and storage of power within the system.