When we wrote back in December that alternative battery chemistry specialist EnerVenue of California had 7GWh of existing orders, we never said much about just how it plans to go about supplying this much battery in the near term. Now its gigafactory plans are out of the bag, with a first stage set at 1 GWh, at a one-million-square-foot manufacturing facility in Shelby County, Kentucky announced this week. Of course it would take 7 years to supply its existing contracts if that was all that it built, but like most start-ups, it has to put its trousers on one leg at a time, and it says it will ramp this to a 20 GWh factory, costing some $1 billion, in…