A vehicle (150) includes a fuel cell stack (151) started below freezing,
by connection (158) to the vehicle propulsion system (159) within a few
seconds of starting the flow of fuel (179) and oxidant (173), or when
open circuit voltage (155, 156) is detected. The fuel in excess of
stochiometry requirement and the oxidant in excess of at least twice
stochiometric requirement, are at atmospheric pressure and at 4 kPa (0.6
psi) or more above the pressure of any water in said water passages due
to a water passage vacuum pump 205, and may be below freezing. Water
transport plates (84, 86, 88, 89) have water passages connected to a
water circulation loop (170) including a reservoir (164) having an
auxiliary heater (161) connected (160) to the stack. Warming of cell
stack materials and ice in the water transport plates, heat of fusion of
melting ice, warming of melted water, and evaporative cooling of water
melted in the water transport plates keep the stack cool until liquid
coolant is circulated.