Can an Electric Car make your system sound better

Is there testing that I can do to know the quality (Lack of noise) that a specific inverter has?  Or if the inverter has good spec what to look for.  I have Roon and use a raspberry pi as one of my endpoints and use a usb battery to power it.  There is no conversion AC /DC  so I assume that it has good clean power.

not the same but i know a few people who use a battery back up system like the Yetti, ecoflow, etc. that are basically a battery and inverter in one package usually sold as back up power. The inverter is actually quite good in many of these battery back up systems and reasonable pricing. they gave a noticeable sound improvement in the system i listened to with the most change in the noise floor. my friend runs his whole system from one and uses a solar panel to charge it, the panel is part of the package he bought. 

Thanks - I figured that would be the downfall of my idea.

Your stereo will be powered by battery which sounds like a good idea to a layperson.  What most fail to realize is that there is a cheap inverter that turns the battery DC into 120V ac.  Since there is no need for quality AC for most things, it is likely the inverter is nothing to brag about.  Of course your house current is probably pretty  bad also.  But I would expect it to be more stable than your car.

Jerry