I've never seen an L298 used in that manner; I doubt it would work, because if it did, such an application would be described in the datasheet for the device (you would do well to read it, too). It is possible with the L298 (and with that board, if the schematic is accurate) to operate in "bridge mode", to double the current output of the L298 (to about 4 amps) - so in other words you can control either 2 x 2A (max) DC motors, or a single 4A (max) DC motor (or use the L298 to drive a single bipolar stepper, of course). Doubling the voltage, though? I don't think that will work...
Hey cr0sh, thanks for reply
Yes, I read that could "double the current" when you put the outputs in parallel.
I looked into the datasheet, is not really about increasing the V that way.
I am very afraid to make that connection. I do not think I will. xD
The best would be to connecting two batteries in series, and then put the 24V in the driver, isnt it?