The Natural Philosopher wrote:

Its not dependent on the size of the battery, though you need some
pretty serious charging equipment to do that. But we are talking
multi-million pound motorway service stations here. I don't see any real
problems in running a small substation in to them, and having the odd
440v 120A 3 phase connector littered around the parking lots..or
whatever combination of volts and amps seems most appropriate.

A big set of AAs[1] might be more workable. Go for a standard cell size
that can be swapped out as well as charged in situ. That way you have go
to a filling station for a cell swap, and they could slow charge a pile
of them off peak. You could also slow charge at home etc.


[1] obviously not real AA cells - but some standardised size

--
Cheers,

John.

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