When the battery needs a charge, it can be plugged into a regular 120-volt wall outlet, although that may take several hours. The time would be brought down to one hour at a commercial charging station.
I wonder if that "one hour" refers to the Empulse or the Zero. The Zero has the CHAdeMO option which can supply a 1 hour charge, so probably it refers to the Zero. However..
Brammo already packages an external Eltek Powercharger 3000 for the Empulse TTX. It should be possible to team both an offboard and an onboard charger to charge at 6 kW, or a ~95% charge in 1.5 hours from J1772. Perhaps the offboard charger could fit into the saddlebags, though supplying adequate airflow might be difficult.