So I would like to discharge supercapacitors and batteries from li-ions to car lead acid batteries with a max power of about 500W with voltages ranging from 3.7 V to 16 V but I am not sure what the correct resistance value should be for my requirements.

I have already bought 5 x 100 1 Ohm resistors encased in an aluminum shell that I plan on placing on a very large heatsink with two fans in push/pull configuration to manage the heat output of 500W.