Khalakhaljid Sands was one of many battles which Genghis Khan fought to try to unify the tribes of Mongolia under one banner. The battle was against Jamukha, who had risen against Genghis. Genghis lost this battle, and his son Ogedai was missing and wounded on the battlefield. The Secret History of the Mongols states that Genghis's adopted brother and companion Borokhula rescued Ogedai after the battle.
The original article can be found at Khalakhaljid Sands and the edit history here.