Home battery storage market expected to boom in 2016., page-17

rattle

I had a quick read of the Redflow document.
They certainly lose charge and they can run down to zero without damage. What you are talking about is they can be left alone and not used for an extended period and suffer no deterioration or loss of output as does a normal battery. But you do have to use a voltage after that the reenergise them but they come back to the charge they were left at.
The thing is you cant let the power in a house run to zero and the power distribution system would stop power flowing to the house after it fell below 240volts, you cant let computers and other electrical appliances run below their nominal power ratings.

Here are the stats from the Redflow site

it is a 210Ah, 48V nominal
battery (a nominal energy storage and delivery capacity of 8kWh at a typical roundtrip​

efficiency of 80%), with a voltage ranged between 36V and 57V.

In normal battery terms that means they can theoretically supply 1 amp for 210 hours or 210amps for 1 hour.
So you are going to need quite a few of them to power a house.
They are 250kg in weight for each one.

Cant find a price for them but I would bet they will be very expensive.
They do sound very interesting though, more so for larger instillations as you speak of.
I would like to have a power system using these bats but the price would be a killer for sure.