A "Stornoway Gazette " writer dubbed the song an "extreme-power-ballad maelstrom" and felt that it was one of the album's instances where "pop metal actually does justice to both musical genres". A writer from the "Leader-Post" praised Lee's "stunning notes" on "Lithium" which he further described as the equivalent of "My Immortal" from the band's debut studio album "Fallen" (2003). Saying that it "could blow a hole in the wall", a writer from "Billboard" went on to describe the song as "the kind of number Evanescence was born to perform: cinematic production, gripping orchestration and Amy Lee's voice gliding through verses and soaring over choruses". The writer finished off his review by noting that Lee's "latest musical affair with darkness is captivating" and it would almost make listeners "wish heart was broken". A more mixed review came from R.J. Carter of the music website "The Trades", who felt that "Lithium" was one of "The Open Door"s two songs which would have been better off as bonus tracks, adding "['Lithium' stretches Lee's glass-shattering capabilities to a level which, at one point, I'm sure deafened the German Shepherd down the street".