Looking at the datasheet, I see some interesting things:
1. The battery is connected in parallel with the PV strings.
I suppose this is the beauty of the SolarEdge approach of using the optimizers at each PV module. Those DC/DC converters can perform the function of peak power point tracking and still provide whatever battery voltage is required given the operating conditions of the system.
2. Only ONE battery is allowed to be connected.
This seems a little odd since Tesla included a DC/DC converter in EACH PowerWall. My conclusion is that those things are meant to be connected in parallel. (Note 4 does say that you should contact SolarEdge if you wish to connect more than one battery.)
3. Maximum continuous power draw from the battery is 3.3 kW.
This tells me that they REALLY mean it when they say that you can only connect one battery. Tesla says their batteries are limited to 2 kW output power, so connecting two would mean 4 kW. So if you can only connect one, then you really can only get 2 kW output power. Does this mean that you are limited to 2 kW at nighttime when in standalone mode? If so, most will find they cannot even run the distribution fan in their main air handler. (Forget about running the heat pump, if you have one of those!)
At this point, I'm thinking the addition of the battery provides some utility, but limiting the output power to 2 kW when there is no sunlight is a pretty severe limitation. I really don't understand why they cannot allow higher power operation from the battery alone given the 7600 VA rating of the inverter in this unit.
Once we have pricing information, we should be able to compare the per-kWh cost of this solution when compared with the $0.13/kWh we get for the Enphase AC Battery
(assuming the application for both is time-shifting consumption). Tesla currently lists the PowerWall at $429/kWh, which is about half of Enphase' AC Battery, which comes in at $833/kWh, but PowerWall contains no inverter. The PowerWall solution might be cheaper if more than one PowerWall is attached to the StorEdge inverter.
But apparently there is a limit of only ONE PowerWall.