This is my favourite subject (being a solar guy of 20+ years).
I continuously hunt for the right type of inverter charger to suit Zero's - it's actually easier on early 48V models but the newer 120V nom battery is much harder. best recent tip I have is that in Japan, a common system voltage for home storage is 100V DC (ish). So, LG for example and a number of others have Lithium home batteries at that voltage to suit that market. This means they have nom 100V DC inverter chargers too and I'm told Omron are one of the better ones. I can't find anything about a 100V model though, perhaps cos Im down under.
So, anyone got a freind in Japan who they can lean on for some hunting around?
BTW, the nom 300VDC Tesla powerwall does not include an inverter charger. Currently, you are restricted to SolarEdge, Fronius & a new SMA.
Talking to inverter charger engineers I know, the cost of manufacturing a reliable, quality, approved inverter charger to suit is many hundreds of thousands of dollars. The HV DC requires some high levels of engineering and isolation that pushes up engineering, component and approval costs.
Also, interesting to note that most of the inverter chargers for stationary batteries (aka Tesla, LG Chem etc) are around 3kW so not powerful enough for our needs. This is driven by the fact that most of the home batteries can only deliver around 3-4kW peak, so it's unlikely we'll see much above that, unless you start looking at commercial scale inverter chargers.