I have bought Dell Inspiron 15R N5110 Battery one week ago.
It has following no. printed on the sticker,
I hope someone will answer as early as possible.
Thank you for writing to Dell Community Forum.
Yes this is a original Dell battery. The wear level depends on how the battery is charged and used. You can check the below link for best practices to increase the life the of battery:
DELL-Akshatha MSocial Media Support#IWork4DellDell Support Videos Drivers and Downloads