Powell made his first blues records by courtesy of Bo Carter, who set up a 1936 session for Bluebird Records. Carter heavily influenced his guitar playing, in sometimes discordant duets with Willie (Bill) Harris. Powell's singing, though warmer than Carter's, had a similar clarity. Powell recorded as 'Sonny Boy Nelson', Nelson being his stepfather's name, and besides his own titles accompanied his then wife, Mississippi Matilda, and the harmonica player Robert Hill. Powell and Matilda separated in 1952, and he retired from music soon after. In the 70s, he was still a skilful guitarist, and was persuaded by Bo Carter's brother Sam Chatmon to perform for white audiences, although it was not long before he retired again because of his second wife's health problems. After his wife's death, Powell resumed touring and recording, and remarried, but his own health deteriorated severely, ultimately leading to his death.
Powell died in November 4, 1998 at the Delta Regional Health Center in Greenville, Washington County, MS, and buried at The Evergreen Cemetery in Metcalfe, MS.