The HP 9AF01AV is a rechargeable battery module for notebooks in HP’s Notebook Modules 10xx range. Its four-cell design and 54 Wh capacity identify it as a long-life battery for compatible configurations in that range.
The listed charge capacity is 3.54 Ah (3540 mAh), and the battery uses lithium chemistry. These specifications describe this particular replacement module.
For notebook replacement, check that the configuration is compatible with part 9AF01AV.