Is there any limit to number of markers that can be placed on google static maps?

The documentation for static maps states:

URL Size Restriction

Static Map URLs are restricted to 2048 characters in size. In practice, you will probably not have need for URLs longer than this, unless you produce complicated maps with a high number of markers and paths. Note, however, that certain characters may be URL-encoded by browsers and/or services before sending them off to the Static Map service, resulting in increased character usage. For more information, see Building a Valid URL.

I am pushing over 16000 markers with no problem at all, not even performance. I am using the javascript API, as long as you can put that into a variable, and push it to the canvas at a reasonable pase (1 per seccond is the speed i am pushing the markers ) there's no problem

As far as I know there is no limit on how many markers you can add to a google-maps based map - however the performance of your map will decrease when you add a lot of them.

There is a nice article on developers.google.com (https://developers.google.com/maps/articles/toomanymarkers) that shows how to deal with lots of placemarks by either clustering them or rendering them on a separate layer.