+2 for usb stick. I use a sandisk ultrafit like this. Its tiny and can be left in place without danger of being knocked.
Its a good idea to digitise your CD collection anyway , as a back up in case of CD damage.
https://www.ebay.co.uk/itm/203625132004?hash=item2f6900efe4:g:tMgAAOSwmfxhSw9g Lots of advantages over CD. No in car storage problems for discs ,or player, or additional wiring. Or scrabbling around changing discs (a distraction even of the passenger does it) The discs wont get scratched ,warp ,peel or otherwise become unusable.
You can omit copying over tracks you never play ,create playlists taken from multiple CD's, or alternatively create your own 'albums' of favourite tracks.