A bilitrium grenade was a weapon used in the 24th century.
The power cells of such weapons leaked anti-protons; in turn, this could be used in tracking these grenades.
In 2369, Benjamin Sisko discovered Bajoran terrorists planting them in docking pylon 3 of station Deep Space 9. With Jadzia Dax using barely functional sensors, Sisko managed to defeat the terrorist plot, locate the grenades and use emergency ejection tubes to send the grenades harmlessly into space outside the station. (DS9 video game: Crossroads of Time)