We recently received a large set of .eps files that needed to be scaled, optimized and converted to .png format to use in an iOS and Android project. Here is a simple script you can use with Illustrator to process these. Save the code below as a javascript file. Then in Illustrator navigate to choose File > Scripts > Other Script and select the script.

var destFolder, sourceFolder, files, fileType, sourceDoc, targetFile, pngExportOpts;

// Select the source folder.
sourceFolder = Folder.selectDialog( 'Select the folder with Illustrator files you want to convert to PNG', '~' );

// If a valid folder is selected
if ( sourceFolder != null )
{
    files = new Array();
    fileType = prompt( 'Select type of Illustrator files to you want to process. Eg: *.ai', ' ' );

    // Get all files matching the pattern
    files = sourceFolder.getFiles( fileType );

    if ( files.length > 0 )
    {
        // Get the destination to save the files
        destFolder = Folder.selectDialog( 'Select the folder where you want to save the converted PNG files.', '~' );
        for ( i = 0; i < files.length; i++ )
        {
            sourceDoc = app.open(files[i]); // returns the document object

            // Call function getNewName to get the name and file to save the pdf
            targetFile = getNewName();

            // Call function getPNGOptions get the PNGExportOptions for the files
            pngExportOpts = getPNGOptions();

            // Export as PNG
            sourceDoc.exportFile( targetFile, ExportType.PNG24, pngExportOpts );

            sourceDoc.close(SaveOptions.DONOTSAVECHANGES);
        }
        //alert( 'Files are saved as PNG in ' + destFolder );
    }
    else
    {
        alert( 'No matching files found' );
    }
}

/*********************************************************

getNewName: Function to get the new file name. The primary
name is the same as the source file.

**********************************************************/

function getNewName()
{
    var ext, docName, newName, saveInFile, docName;
    docName = sourceDoc.name;
    ext = '.png'; // new extension for png file
    newName = "";

    for ( var i = 0 ; docName[i] != "." ; i++ )
    {
        newName += docName[i];
    }
    newName += ext; // full png name of the file

    // Create a file object to save the png
    saveInFile = new File( destFolder + '/' + newName );

    return saveInFile;
}

/*********************************************************

getPNGOptions: Function to set the PNG saving options of the
files using the ExportOptionsPNG24 object.

**********************************************************/

function getPNGOptions()
{
    // Create the PDFSaveOptions object to set the PDF options
    var pngExportOpts = new ExportOptionsPNG24();

    // Setting PNGExportOptions properties. Please see the JavaScript Reference
    // for a description of these properties.
    // Add more properties here if you like
    pngExportOpts.antiAliasing = true;
    pngExportOpts.artBoardClipping = false;
    pngExportOpts.horizontalScale = 350.0; // scaling to 350%
    pngExportOpts.saveAsHTML = false;
    pngExportOpts.transparency = false;
    pngExportOpts.verticalScale = 350.0; // scaling to 350%

    return pngExportOpts;
}