Issues with updating modules on Drupal 7
I have encounted this in the past and usually you get a module that causes an issue with AJAX. 

What I would suggest is to update modules manually (download from drupal.org, extract and upload then run update.php) or via drush one by one. 

If you are doing multiple modules at once this can happen quite often. 

Also make sure you have Overlay module disabled as for some odd reason this can cause the same error. 

Your best bet is to update modules one by one to isolate which module is causing the issue.