This can be done with a web-based task scheduler that performs work when individual even happens, IF THIS THEN THAT (ifttt.com) is very much useful in all aspects and in the case of creating a backup it is way more useful.
How to backup Google Contacts into Google spreadsheet
- Create an account on ifttt.com.
- Create a new receipt
- Choose Google contacts in "If" option and connect grant access to your Google contacts.
- Now choose option added a new contact to trigger an event.
- Select Google drive and connect it.
- Now choose to append in a document option (if you want to create a separate document for each contact) and add a row in a spreadsheet to store all contacts in a spreadsheet.
- Define spreadsheet name and click on create recipe.
Now all your contacts will be stored in a spreadsheet without any issue, and you can access them from Google Drive.