How to check whether the battery of dell laptop is original while purchasing new laptop?

hi friends i am going to purchase a new dell laptop but some of my frenz told that the original battery can be replaced by the duplicate by the shopkeeper or retailer .so is there any method to check whether that battery belongs to same dell laptop. any method if i know then i will be thankful to u.

 

The box should be sealed when you buy it.

 

there's no way to do that unless you contact the manufacturer, and even then...