AC500/B300S Battery Maintenance

What is best practices for battery maintenance on the AC500/B300S?
I’m reading we should do a complete discharge every 6 months.
What is the recommended way to do that?
I also see a “Deep Discharge” options on the menu.
Is that something we should be using and how?
I’m also interested in hearing from other folks and the process that you’re using to maintain your batteries

Thanks,

Rick