I was contacted by Zero factory personnel and informed of what the current situation is. It turns out that all one needs is an adapter cable (Zero sells them) and the accessory external charger can be plugged directly into a battery that is not on the bike. No fixture is needed to hold the battery.
This is great news because it is less to carry on a trip and of course just needing an adapter cable makes it very little additional cost when buying the accessory charger.
Apparently those riding the Zero models with plug-able batteries always knew this, but since I have only been exposed to Zero bikes that didn't have removable batteries, I didn't know about this feature. I'm glad to find it is so simple.
I will most likely buy one of the accessory chargers and the cable.
Not having to physically put the bike where AC power is, when I need to charge, will be a big help. Some motel owners have not been real happy with me wheeling the bike into the room. I usually explain that it is more like an electric wheel chair than an oily motorcycle with flammable fuel aboard. However, muddy tires are another story.
I also carry a very short
flat extension cord that will fit under most motel room doors when closed. No more now, with my new FX.
Trikester