My experience is that the cheap e-bay batteries just makes the phone unstable. The 2450mAh gold battery works fine. However, here is an x-ray of the three different batteries. Looks like there is a little difference in the circuits. Even though it doesn't say much, I think it's interesting, but then again I'm a bit of a nerd....
AFAIK Samsung batteries are "bumb" ones- there's only overcharge protection circuit (even for high-end models) and NFC antenna for "N" model.
Some older models (like i5700) had also resistor to distinguish original batteries from knock-offs (if resistor was missing or had incorrect value bootloader didn't charge the battery at all).
I'd say there's not much to investigate