I have a single Redflow battery in a Victron energy system (yes, I know that's not ideal for various reasons.) Because it does a full discharge every three days for maintenance, I thought it would be useful to be able to push the discharged energy into my electric car, rather than having it pushed out to the grid.
So I wrote a script to do exactly that.
The Python script at https://github.com/slamble/redflow-victron-ev/ checks the battery for maintenance; if the battery has put itself into maintenance mode, it connects to a Victron EV charger and directs it to start charging at 6 amps (the minimum). That induces the battery to discharge at a higher rate than it otherwise would discharge at, and the EV charger directs the current into the car battery. Once the battery has dropped below 10%, the charging is shut off and the battery left to discharge as it normally would.
The script also checks to ensure the AC load doesn't get too high, shutting off charging if it does (eg: if I'm cooking dinner.)
Just putting the script out there in case it's useful to others. Suggestions for improvement are welcome, as are pull requests (though bear in mind that I'm not in a position to test fixes for multiple batteries, three-phase installs, and a few other things that I've noted as deficiencies in the script.) Some user fiddling is required to get it operational in any given site - the IP addresses in particular are geared towards my setup, and probably won't translate to anybody else's environment. I've tried to document this as best I can.