DIY Pika powerwall possible?

[yeldarb]

As shown in my profile, I have 32 panels of 300W/20V feeding 4 Pika PV Link/S2501 MPPTs into a Pika X7601 Islanding Inverter.

Pika was headquartered near Portland, Maine, near where I live and I got the chance to go down and see their facility and talk to them before I went with their system. The entire system has several modes, works great and has been trouble free.

I'm currently grid-tie but I'd like to add batteries, both as outage backup and SHTF. But Pika/Generac has a proprietary system they call the RE/bus, which uses the power connections to mux data for control. The Panasonic powerwalls they sell are super expensive: $2400 for the cabinet and $1700/each, min 3, total $7500 for a 9kW powerwall. The Pika system seemed like a good idea at the time but it appears I'm locked into their system.

Is anybody out there familiar with the Pika systems? Are there any DIY or cheaper alternatives? I don't mind complex DIY projects.

 

[Stefanseiner]

I guess you have to find out if your system is able to communicate with the battery or have to communicate with the battery.
I don't know Pika but the voltronic inverters (MPP Solar, Infinisolar, AXpert ...) have a communication-port for some batteries e.g. the integrated bms inside the battery, but they don't need them to work. It only allows a better configuration but is not necessary