When was then terracotta army's first battle?

The Terracotta Army is believed to have been created during the reign of Qin Shi Huang, the first Emperor of China, around 210-209 BCE. While it is not directly linked to a specific battle, it was meant to accompany the emperor in the afterlife and protect him in battle. The army was discovered in 1974, revealing thousands of life-sized figures, but no battles are documented in relation to the army itself during its creation.