Chrome crashes when exporting file via Filesystem API

Im trying to run in-browser encryption application which uses jQuery 1.10.2 and CryptoJS 3.2.1 the problem that I face starts at around 2mb files. File can be encrypted just fine, but when a data URI is created for the file it crashes the browser.

I would like a way around this to make it possible to encrypt files up-to 50mb's without browser crashing.

Here is the current snippt responsible for file saving via FileReader API

var reader = new FileReader();

        if(body.hasClass('encrypt')){

            // Encrypt the file!

            reader.onload = function(e){

                // Use the CryptoJS library and the AES cypher to encrypt the 
                // contents of the file, held in e.target.result, with the password

                var encrypted = CryptoJS.AES.encrypt(e.target.result, password);

                // The download attribute will cause the contents of the href
                // attribute to be downloaded when clicked. The download attribute
                // also holds the name of the file that is offered for download.

                a.attr('href', 'data:application/octet-stream,' + encrypted);
                a.attr('download', file.name + '.encrypted');

                step(4);
            };

            // This will encode the contents of the file into a data-uri.
            // It will trigger the onload handler above, with the result

            reader.readAsDataURL(file);
        }
        else {

            // Decrypt it!

            reader.onload = function(e){

                var decrypted = CryptoJS.AES.decrypt(e.target.result, password)
                                        .toString(CryptoJS.enc.Latin1);

                if(!/^data:/.test(decrypted)){
                    alert("Invalid pass phrase or file! Please try again.");
                    return false;
                }

                a.attr('href', decrypted);
                a.attr('download', file.name.replace('.encrypted',''));

                step(4);
            };

            reader.readAsText(file);
        }

What can I change in above code to allow for larger files to be encrypted and decrypted?

Live site: droplet.so (currently capped at 1.5mb otherwise browser crash is guaranteed)

Kindly thanks in advance.