Each plate [of a battery] before being inserted
into acid, is neutral;
How sure are you that they are neutral?
How do you know?
I claim that in equilibrium, two dissimilar chunks
of metal are not electrically neutral. They will
carry a charge that depends on the materials, and
on the (inverse) distance between them.
There is a device called a Kelvin bridge that is
based on this. It is used to measure the work
function of materials.
The fact that things have work functions, and
therefore are not neutral in equilibrium, is a
key part of the physics of batteries.