top 10 energy storage integrated manufacturers Industry professionals energy storage systems (ESS) $546 billion by 2035 Solid-state batteries AI-driven optimization virtual power plants (VPPs) Flexible Power Units sodium-ion batteries 40 GWh storage pipeline BESS (Battery Energy Storage Systems) energy storage integrated manufacturers Vertical integration Grid marriageability LCOS (Levelized Cost of Storage) “mining” their own materials energy storage integrated manufacturer