I just bought DELL battery online and want to check whether it is original or fake. Here is the part number that is on the box 4YRJH.
The problem with battery is that it shows 60% and next moment it is 8%.
If it was purchased from Dell, it's genuine and carries a 12-month warranty.
If it was purchased anywhere else, contact the vendor to find out - only they can tell you.
A counterfeiter can print fake battery labels using a real Dell serial number from another Dell battery. If you did not purchase the battery directly from Dell, there is no way to know if it is a Dell battery or a counterfeit.
If it is an original battery, it could also be up to seven years old, which is about the age of the system that it's designed for.
The Dell part number is only a small part of a long alphanumeric string that includes the date code (date of manufacture). It will start with CN, KR, JP etc -- depending on where the battery was assembled. If that's missing from the battery label, the battery is almost certainly rebuilt or third party.