In one of my recent projects, I had to execute a bat file which was expecting one argument before execution. Content of bat file was like this :

"%~dp0phantomjs.exe" "%~dp0..\examples\rasterize.js" "%1" "%~dp0twingle.jpg"

If you Analise the above code then you will see that it is expecting the parameter "%1" so i had to pass this parameter using C# code. Here is the method that solved my purpose

 Void  ExecBatFile()
        {
                System.Diagnostics.Process proc = new System.Diagnostics.Process();
                string filePath = Your File Path
                proc.StartInfo.FileName = filePath;
                proc.StartInfo.Arguments = String.Format("{0}",http://findnerd.com");//Passing arguments for the first parameter in bat file
                proc.Start();//Starts the Project
proc.WaitForExit();//Makes the process wait till the bat file execution is not     completed
        }

Using the above method, I passed "http://findnerd.com" as parameter value for first argument. This way i was able to execute the bat file with parameter