Hi TODAYPKS,

The n4050 usually was shipped with 6 cell batteries.

You could enter the service tag here and check for the original system configuration and the battery info should be listed.

I am not sure if we still have the batteries in stock for this system as it is over 5 years old model.

You could however, order the battery here or through other online / local resellers.

Also, please click my DELL-username and write me a private message with the service tag and your Name for case records.

Let us know if you have any other queries.