To locate the model number on the laptop battery. Flip the laptop upside down. Slide the battery out of the laptop and look for the serial number that is printed on the label on the back of the battery. If you still can’t find the laptop part number(P/N).

Here is some example of how you can find the part number of the most common laptop brands:

Acer: Acer part number will sometimes start with an “AS” followed by several alphabet &  numeric characters.

Asus: Most of the time the part number is near the ASUS  logo on the battery. An Asus part number will be between 4 and 6 characters, and will start with a capital letter, e.g. X5DC, A32-Z96, or K52F’. 

Dell:  You will find the Dell part number on the label affixed to the battery.  Locate the country of origin (“Made in …”) label affixed to the battery and the part number will be below or above it.

Example: 0CP289 , 312-1205 ,WJPC4 or 9T48V.

HP/Compaq:. To find your part number, look beneath the laptop for a sticker containing part number information.  There should be a white sticker with a barcode on every battery. Usually, the sticker shows, “Replace with HP spare” and following that are 6 digits with a dash and 3 more digits. This 6 digit number is a part number of HP battery.

Sony: Sony battery model number should start with VGP-BPS  or  VGP-BPL  and contain 2 to 5 combinations of characters. Some examples of Sony part numbers are  vgp-bps35, vgp-bps35a or VGP-BPS13Q.

Lenovo:  Lenovo batteries are most of the time listed with the label of   FRU p/n and ASM p/n.Some example of Lenovo part numbers is ASM 42T4703 or FRU 42T4793.