a novel marco channel cooler (macc) has been developed for packaging high power diode vertical stacked (hpdl) lasers, which eliminates many of the issues in commercially-available copper micro-channel coolers (mcc). the macc coolers, which do not require deionized water as coolant, were carefully designed for compact size and superior thermal dissipation capability. indium-free packaging technology was adopted throughout product design and fabrication process to minimize the risk of solder electromigration and thermal fatigue at high current density and long pulse width under qcw operation. single macc unit with peak output power of up to 700w/bar at pulse width in microsecond range and 200w/bar at pulse width in millisecond range has been recorded. characteristic comparison on thermal resistivity, spectrum, near filed and lifetime have been conducted between a macc product and its counterpart mcc product. qcw lifetime test (30ms 10hz, 30% duty cycle) has also been conducted with distilled water as coolant. a vertical 40-macc stack product has been fabricated, total output power of 9 kilowatts has been recorded under qcw mode (3ms, 30hz, 9% duty cycle). © 2017 spie.