You can use the same entity but I guess you want to use different objects of this entity. You can only pass a single object to a page, that is correct, but you can have multiple dataviews. They can get the object from a datasource microflow.
You could also have a second wrapper entity that is associated 1-* to your chart entity, pass this wrapper to your page and show the associated chart objects in a listview or a template grid. This would make everything pretty flexible and the amount of charts could be dynamic.