Adding battery backup only for emergency to a rooftop SolarEdge system, DIY and cheaply?
I am a home owner and I have a grid-tied rooftop SolarEdge system. I live in an suburb area in northern California (a lot of sun). My area's electricity is quite stable and if it had an outage it was normally for only a few hours. However there are still some natural threats, such as winter storms and wild fires, which could damage the infrastructure to the whole region. Because it is rare and I only need keep essentials such as my refrigerator running, I don't want to spend a lot of money. Currently those "solar generators" are quite convenient and in low cost. Is there a way to utilize my rooftop solar panels to recharge a solar generator in case of a long power outage?
BTW, I am kinda handy with an electrical engineering background. I have being thinking going to the roof to run a wire directory from a solar panel (rated 330w), bypassing SolarEdge Optimizer, to feed into a "solar generator". How hard is it? It seems all the solar panel wires are hidden in the tracks. I hope there is a more elegant way anyway.
PS, I am on NEM2.0, so going to commercial solutions, such as Tesla Powerwall, is not attractive to me.