High energy density entrainment-based catalytic micro-combustor for portable devices

•Energy-dense combustor features entrainment architecture to enable full portability.•Major electrical saving enhanced by localized ohmic preheat and new wiring scheme.•Optimal flow rates, governed by kinetics/transport in channels, can aid fuel savings.•Cycling tests demonstrate ultra-high thermal mass heating (>41 times its own mass)•Optimized microchannel geometry improves reaction rates/fuel conversion efficiency.