1. A bi-polar charged particle beam delivery system, comprising: a bi-polar accelerator configured to accelerate positive and negative ions in the same direction, the bi-polar accelerator comprising: a plurality of arced sections, and a plurality of bending magnets configured to direct the positive and negative ions around the arced section in the same direction; and a configurable power supply coupled with the plurality of bending magnets, the configurable power supply configured to supply a reversible current to the bending magnets.