If you are full confident & you 100% ensure they will hire you on any cost. Please don't be immotional be practical. Tell them stateway I need % hike to my present salary. You can also tell them about your cash perks like Mobile/Conveyance and data card charges you are already getting from present company but please don't mention wrong salary .
Fixing pay in any organization depends on candidate's profile like experience,qualifications,exposure,his overall track record etc.
If you have done well and feel pretty comfortable in securing the job, you can quote what ever is suitable for your job profile, your experience,exposure etc in any term as mentioned by you like % or amount in lakhs.
If you are not much confident then say as per company norms.