Here’s a heads up for a mistake I made out of ignorance. I had a Titan with 3 of their batteries. At a later date, I purchased one, then a second BigBattery 6,000 kw battery. As I ran multi day tests, I found that one of the BigBattery batteries would not maintain the 29 volt requirement for syncing purposes that is required by the Titan system. It would charge to 29.1 volts, but when disconnected from the charger, it would end up in a ‘rest’ voltage of 27+ volts. Of course there are always ‘small print’ exceptions to most things, and BigBatteries’ small print said that their batteries are considered fully charged at a voltage that is 27 - 28 volts. So, that battery (24V HSKY) can’t be used with the Titan. I’m looking at alternative uses so I don’t have such an expensive paper weight—ha. Like said above, the Titan seems to handle most of my residential home load so as to make a grid out occurrence seem not so bad.