Kelli received a BA in theatre from Mary Washington College in Fredericksburg, Virginia, USA. She then went on to train at LAMDA, where she specialised in lighting. Kelli has also completed an MA by research degree from University of Leeds, which concerned the history of lighting design at the Royal Court Theatre. She is in the final year of a PhD at University of Leeds, where she is examining how lighting designers use language to exercise agency in creative collaboration.

Three days after graduating from LAMDA, Kelli started at the Royal Court as lighting board operator and was promoted to lighting assistant twelve months later. She left the Court after three and a half years for a brief stint with the RSC, and is now based in Leeds where, until September 2010, she worked as a production electrician at West Yorkshire Playhouse. She now designs for small- and mid-scale theatre and opera, mostly in Yorkshire and Lancashire. Kelli is a dual UK/US citizen. 

Recent credits: Dorian (Proper Job Theatre), Medusa (Proper Job Theatre), assistant lighting designer (LD: Matt Haskins) for Opera North fairytale season (The Snow Maiden, Hansel & Gretel and La Cenerentola), Cinderella (Northern Opera Group), You Forgot the Mince (Imagine if Theatre Company), Revenger's Tragedy (Wellfangled Theatre), The Maids, Playhouse Creatures, Miss Julie, Playboy of the Western World (Hedgepig Theatre Company), Othello (York Shakespeare Project), Somebody's Son, Bag Lady (Hidden Gems Productions), 59 Minutes to Save Christmas (Slung Low), Amsterdam (currently on tour), which was nominated for Best Studio Production in the Manchester Theatre Awards.