3 phase from battery power

A device that converts direct current (e.g. from a battery or solar panel) to 3-phase alternating current is called an "inverter". There are plenty on the market. Is this spam or just lazy research?

Not spam or lazy research, I'm aware that the Tesla product can come with an inverter and that there are components that can change single phase to 3-phase but they are not that efficient. I am building a new house and workshop and am designing it to eventually go off grid. The cost to bring 3-phase to the shop from the local utility is substantial. The gist of my question is that is it more efficient to set up 3 batteries with single phase inverters into a 3-phase supply vs using a converter to change from single to 3-phase? Is it even possible? I have strong mechanical knowledge but my knowledge of electrical theory is pretty weak, any help and advice you can give is greatly appreciated. To power both the house and the shop will take 3 batteries (of Powerwall capacity) and a decent solar array. I am looking to maximize efficiency.

If you tried to get three individual inverters to deliver the individual phases of a three-phase supply I would think you would run into horrible problems getting them to run in synchronism at the exact 120 degree phase difference. Better to get a single three-phase inverter and parallel the three batteries into it.

You can get inverters that directly convert DC from a battery into 3-phase AC. You don't need three separate inverters to do this. You really should be consulting professionals. This is a general-interest forum and you are not likely to attract the highest quality of replies because of this.

Thank you all for the advice, I was just curious and btw I have an appointment with an electrical engineer that my architect recommended. I agree, this is a pretty complex situation especially when you throw the solar into it, so to a professional I go