Résumé : I will explain and state a conjecture of Kontsevich, that relates vertex models from statistical mechanics to $E_n$-algebras (i.e., algebras for the n-dimensional little disks operad). I will also give the main ingredients of the proof of Kontsevich's conjecture, that involve discretized versions of the little disks operad. This is a work in progress with Damien Lejay.