Hello,
If I have two batteries 1.5V and first has maximum current(NOT CAPACITY) of 1 Amp and other has maximum current of 2 Amps, If I connect them to parallel will I get maximum current of 3Amps?
Perhaps. I'm inclined to believe so but only to a certain extent. You may end up causing damage to the 1Amp capable cell.
When in parallel, the voltage across the batteries will be the same. When you pull a lot of current from a battery, it's *internal resistance* will determine how far the voltage drops while under load. It's this voltage drop characteristic that may end up causing a higher than desired current draw in the less capable battery.
If I didn't care about the batteries, I would do it... or if I was keeping current draw less than 2A .
Otherwise, find a datasheet on the discharge characteristics for the cell and see if you can match them up. If this can't be done, then use the same type of cells throughout a pack.
*Please note, the 1Amp and 2Amp capable batteries are not what they 'put out' , but simply what they are capable of handling when under load.