Excerpt from A Course In Modern Conjure Lesson 35:
From the Chinese tradition of burning joss papers resembling money as offerings to the dead emerges Hell Money (aka Hell Bank Notes). Whether by syntax, miscommunication, or malice on the part of the printer, the origin of the word Hell on these papers is uncertain. Some suggest the name is a purposeful attempt to translate into English the concept of an underworld prison—Diyu—where the dead await judgement (and apparently do a spot of shopping). Above ground these bills were being bought from religious goods stores that serviced urban Chinese Americans, and which were frequented also by African American conjure workers who adopted these exotic bills into their practices. Hell Money appears in various methods of conjure work, such as in mojo hands, or set beneath candles as prayer papers, or under lodestones on money altars.
Some contemporary bills have replaced Hell with Heaven or Paradise, and these are also used, though for my money Hell will always hold a bit more allure than Heaven.