This is promising to see. At Hyperion we already work with a NYC based energy storage start up, building their team. We've also just started working with Boston based Google incubated and Bill Gates funded long duration energy storage company Malta Inc.
Long duration storage has also been the topic for the last two 'This week in cleantech' Podcasts, with CEOs Javier Cavada (Highview Power) and Ramya Swaninathan (Malta Inc) on the last two episodes. Link here http://thisweekincleantech.com/
The development of systems capable of storing over six hours of energy economically is being supported in New York with an Innovation Challenge launched by the New York Power Authority (NYPA) and Urban Future Lab, a cleantech innovation centre. Also aimed at supporting promising new technologies and business models for electric vehicles (EVs) and their related infrastructure, the challenge will support a “handful” of selected startups to support and help prepare them for working with large utilities.