Google Docs distorts the file, increasing its size. Why and how to fix?

Question

Google

We use PHPExcel to export data to the database.
If you correct, save and use some cells from a standard desktop Excel, everything is ok.
If you change something from a mobile Google Docs, save it and use it later, everything is ok.
Even if you work with DropBox and change cell values ​​online, save and use them, everything is OK.
But if you import the file into the online web version of Google Docs, change (or not change) the cells, save .... then the file does not work in PHPExcel for some reason. What could be the problem?
We noticed that the file size increases by about 4 times. We loaded the original with a weight of 14kb, unloaded (without changing anything) from 49kb. wtf?

Answer 1

Most likely Google uploads the file in a different format.