The growing interest in deploying fuel cell vehicles in heavy-duty sectors and cold regions has imposed more stringent requirements for cold start methods. The alternating hydrogen pump (AHP) method enables efficient cold starts while avoiding failure and degradation caused by freezing of super-cooled water. Herein, the sensitivity of parameters such as the alternating frequency and gas flow rate, as well as the effects of H2 supply methods and power control sequences, are explored for increasing the heating power using the model developed in Part I. With the optimized values, the heating power of AHP is tripled, enabling PEMFCs with graphite bipolar plates to start-up from -30°C to 0°C within 30 s. In addition, the superiority of AHP in terms of capability, degradation, and practical convenience is demonstrated through the comparison with state-of-the-art rapid self-heating method.