Yeah 120W is table stakes. Also Anker wall adapters are insulated that's worse for efficiency. Integer ratios can be done with GaN and class 1 ceramics and st

Yeah 120W is table stakes. Also Anker wall adapters are insulated that's worse for efficiency. Integer ratios can be done with GaN and class 1 ceramics and stray inductance to charge the GaN drain, so they only experience ZVS (they don't need ZCS). Use a resonant gate drive. Efficiencies around 99.8% are feasible for a doubler/halver based on the "3L FC buck" topology, in the 10~30 MHz range.