No backlight due to water

sandy, rice is only good as a first aid. It will not remove all the water and moisture, nor will it prevent corrosion. I suggest you clean your phone once more. Disassemble every part off it and soak it in 90%+ isopropyl alcohol. Clean all the parts with a soft brush, including the logicboard and all cable connectors. Check for burned, missing components. You definitely want to replace the battery. After that, reassemble and re-evaluate. If you still do not have a backlight,replace the display assembly. I can not stress the cleaning enough. If you o not do that, your phone will eventually fail due to corrosion damage. The same goes for the battery. Once a battery has been exposed, you do need to replace it. Hope this helps, good luck.