Vibration Isolation for Battery Box EV Conversion

I am currently building two steel battery boxes that will house 2 modules from a Tesla Model 3 (2 per battery box stacked, supported from the side as intended). This will be going in a 4x4 and may see some off-road use but likely minimal, just typical road conditions. It will be mounted to keep a low CG to the frame so it will be on the sprung side. To me it still seems like you would want to put some sort of vibration isolation but I don't believe Teslas have any. Does anyone have any recommendations here?