Best Way to Compress NES ROMs for RetroArch to achieve smallest file size?

I’m using RetroArch on my LGTV, and it doesn't have a lot of storage. I have a 1G1R NES collection and need to compress my ROMs. What’s the best archive format to use for the best compression and compatibility with RetroArch or any compressed format that the core can run natively?. The goal is to save as much disk space as possible.

TIA

UPDATE: I do have other perfect ways of playing for emulating games. I'm just experimenting with my rooted tv, so please do not ask me to get another device or expand storage.

For people saying that they only take up very small space, my tv has available storage around 900mb usable, and any new app installs can easily take up 100 to 150mb. I have all my roms compressed in 7z format that provide better compression than zip format. I'm just interested if there is a better format/way to save more space.

Im doing this just out of curiosity and not because I do not have a better device/storage solution.