Lenovo Battery Internal 4 Cell 72Wh LiIon

The Lenovo 5B10W51888 is an internal lithium-ion replacement battery for a laptop, supplying power from inside the computer rather than connecting as an external accessory. Its four-cell design identifies the battery configuration for service or replacement.

The stated energy capacity is 72 Wh, with a nominal voltage of 15.52 V and a listed charge capacity of 4640 mAh. The part information identifies the battery type as L21C4P74. These details help distinguish this specific battery when selecting a replacement.

Compatibility information lists Lenovo ThinkPad Z16 Gen 2 (21JX/21JY) and ThinkPad Z16 Gen 1 (21D4/21D5). Check the exact part number and listed model identifiers when matching it to a laptop; the description does not establish compatibility with other models.