The University of Wisconsin-Madison has conducted research on gridded inertial electrostatic confinement (IEC) devices for the past 18 years. There are currently 4 experimental devices operating at voltages up to 180 kV and 60 mA. These devices have uncovered several new phenomena that have greatly improved our understanding of IEC devices. Recent advances include the discovery of a significant negative ion component of DD plasmas and spatial profiles of fusion reactions that did not conform to our prior understanding of these devices. The use of this technology has also contributed to our understanding of surface damage to high temperature in-vessel W components after even low exposures to energetic He ion fluences. Expansion of the voltage-ion current parameter space to 300 kV-200 mA in the near future will help our understanding of advanced fusion fuel cycles.