Researchers develop high-efficiency buck-boost DC-DC converter

 https://techxplore.com/news/2023-03-high-efficiency-buck-boost-dc-dc.html

"98.6%-peak-efficiency 1.47a/mm2 current-density, reduced conduction loss... maintain high-efficiency over the full battery voltage range to extend battery life... four low-voltage power tubes, one flying capacitor, and one inductor... highest efficiency at full voltage conversion ratio and the highest current density at the lowest chip cost"