Prosecutors allege the singer abused the teenager after meeting him at a Chicago McDonald's in 2006.
They want evidence of this, and other alleged but uncharged crimes, to be heard at Kelly's trial in August.
Kelly denies ever abusing anyone, and his lawyers have not responded to the latest allegations.
The Grammy-winner, real name Robert Kelly, is set to face trial in New York next month on charges including child sexual exploitation, making indecent images of minors, racketeering and obstruction of justice.
The charges involve six unnamed women and girls.