Writing 5 blog posts per day can be hard. I'd get writers block as well.
When you find you run out of ideas to write blog posts, it's best to just stop writing for your blog for awhile.
Don't force yourself to write content that you are having trouble coming up with ideas for as it can make the blog post turn out bad.
It's better to have a few quality blog posts than it is to have thousands of crappy blog posts. Google favors quality content over quantity.
So if you have a bunch of blog posts that are of no quality then google may not rank your blog post in the search engines anyway.
If you feel burned out and run out of ideas then it's best to get up from the computer and go do something else for awhile.
A new idea for a blog post will come to you eventually.