William Blake's idea of Hell was very different. In The Marriage of Heaven and Hell he parodied Conventional Christians' ideas of Heaven and Hell, of angels and devils. The Elect (angels) are the CC people, especially the priests. The Reprobates (devils) are those who deny the conventional priests; they have the Energy of Imagination. Blake kept these categories through the course of his poetry;
Eventually it became evident that Jesus was one of the Reprobates; look at Milton Plate 13:
"Around the Lamb, a Female Tabernacle woven in Cathedrons Looms
He died as a Reprobate. he was Punish'd as a Transgressor!
Glory! Glory! Glory! to the Holy Lamb of God
I touch the heavens as an instrument to glorify the Lord!" (Erdman 107)
MHH ends with these magical words:
"For every thing that lives is Holy."
That is one of Blake's statements of Universalism (The original American Universalists believed that everyone in the world was and will remain a child of God.)
Blake's MHH was likely a response to Swedenborg's Heaven and Hell, published in 1758, the year Blake was born. Blake, in his early days, was influenced by Swedenborg, but by his late twenties he had become disenchanted with S's thought.
Quoting Wikipedia Swedenborg's Heaven and hell "is a detailed description of the afterlife where people go after the death of the physical body. It deals with God, heaven, hell, angels, spirits, and devils, which the author claimed to have witnessed first hand."
Blake dealt with all these subjects in his MHH, but his perspective on them was far different from those of the earlier writer.
We may read Blake's definition of Hell in Erdman 590 (one of Blake's Annotations of Lavater):
"to hell till he behaves better. mark that I do not believe there is such a thing litterally. but hell is the being shut up in the possession of corporeal desires which shortly weary the man for all life is holy."