Infocards don't work that way. They pop up when (and only when) the user mouses over particular objects. Infocards disappear when the user moves her cursor away. Changing this function of infocards ruins their purpose -- to provide a maximum amount of information to the player, without filling the screen with the UI.
Anyhow, the solution to this is relatively straight forward. Give the Elementopedia a button on the main UI, and have it automatically display the page of the currently-selected object when clicked. The downside of this is that you wouldn't be able to go directly to the Elementopedia page of anything that can't be directly selected. However, if the infocards are done right, you shouldn't need to ever access the Elementopedia for this information.