DigiNow and Electric Motor Werks just announced a new product - the Super Charger Charge Tank - that slots right into the Power Tank area on Zero S/SR/DS bikes. It provides up to a 9 kiloWatt charging rate which means for a 1 hour or so recharge time, in the right conditions.
That means 70-100 miles of riding range, then a 1 hour recharge time, and therefore enough autonomy to make long range riding possible.
DigiNow's Brandon Nozaki-Miller told me that the charger can be integrated with other vehicles - like the Vectrix. The charge voltage is adjustable, and the input and output connectors are all modular.