They can't be pure capacitors, otherwise the charge would be leaking away. No capacitor in the world is going to be reading .6v three days after being charged t

They can't be pure capacitors, otherwise the charge would be leaking away. No capacitor in the world is going to be reading .6v three days after being charged to 9v. Also, the paragraph about the piezoelectric effect in salt is incoherent nonsense. There could be a plausible electrochemical effect causing a change in the output voltage when the cell is heated; but the .1v change resulting from vibration has to be pure measurement error. That is quite plausible, since she's using a three digit hardware-store multimeter, and .1v is the smallest possible change it can measure in the 200 volt (?!?! 200 volt mode when measuring the voltage of an electrochemical battery?) range mode.