Quote:
Originally Posted by gruundehn
...thus, by Ohm's Law (E=IR or more accurately I=E/R) voltage happens. Any EMF generated is a byproduct of the fact that the battery is releasing electrons.
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It's actually the other way around. The metals/salts in the battery have an inherent voltage (EMF) differential dependent on the chemistry of the combination of salt/ions/metals/acids. The current flow depends on the load attached across the voltage. If you put a wire across the battery then the only 'load' is the internal resistance of the battery, which is quite low. As a result, LOTS of current flows, usually heating up the wire and making it combust, or simply get hot enough to melt the guts of the battery.
In electronics you pretty much always have a voltage differential and the actual current drawn depends on the load. You can create 'current sources' but they are basically self-modulating loads that balance out resistance with the real load so the real load sees a constant current.