Lenovo and IBM Battery Part Number Identification
Lenovo and IBM are the same company. Lenovo often lists several part numbers, one is called “FRU p/n”, on is called “ASM p/n”, and occasionally the model number is just listed on the battery with no preface. Also on many Lenovo cartridges there is a red or orange circle with a number inside it (also may contain a + sign).
Examples of Lenovo part numbers: