At the listed price and efficiency losses, plus the limit in power output probably means these won't be the wunderkind of energy storage--but having more options and more competition in distributed energy storage is always wonderful.<p>Additionally, just being able to blunt peak demand makes it a lot easier to work with renewables, or other on-demand power concerns.<p>Keep in mind also, lithium-ion tech has come a very long way in the past decade or so of wide usage. Maybe it's naive, but I'd expect to see similar strides made in hydrogen fuel cell if it starts a similar adoption curve.