Adding batch files as a service is a little bit of a kludge, you are much better off converting your batch file to a powershell file. If you need to do it, then here is how.
First create the service using the SC command.
SC Create "MyCoolService" BinPath= "c:\program files\my cool service\mycoolservice.bat"
*Note the space after the '='
The go into the registry and locate the service you created in:
Here's the kludgy bit, you cannot spawn a batch file from a service so you have to run CMD.EXE and have that run another CMD.EXE which will continue after the service fails to start. So change the 'ImagePath' key to:
cmd /c cmd /c c:\mycoolservice.bat
When you try and run the service it will look like it fails, but it spawns your batch file anyway!