How can i calculate the maximum current a battery can provide if the only information i have is: 7.2 V / 11.5 Wh / 1600 mAh.

I know that if i can multiply C rate with Ah i can get maximum current of battery, however, most of the batteries lacks this information. Is there any other to calculate maximum output current of battery?

No.

You can measure internal resistance, you can even look up the datasheet, but there

isn't enough information to calculate power from capacity as they are different properties.

For instance a vehicle 12V battery and a deep cycle 12V battery might look the same, weigh the same,

have similar capacities, but one could be rated for 800A, the other for 50A...