Can someone explain why the direction of the current in the image dlgoff posted when the transistor is closed seems to be from negative of the battery to the positive? Doesn't current go from positive to negative (opposite direction of electrons).
Good catch. That's the convention of current direction I've always used in circuit analysis. e.i. From the highest "+" potential (voltage) to lowest "-" potential (voltage)
But like Windadct says,
... it is technically correct, esp to a physicist, if you consider that the electrons are negatively charged (-).
Mathematically, those arrows in the pic you're asking about can be considered to represent "negative current". Here's an example where everything works out mathematically.
Magnetic Force on a Current