Update: This firmware was updated on September 14, 2010. The update includes a second fix, also for the full charge capacity value and the same symptoms. This second fix applies to all of the supported batteries listed below but fixes a problem which can only manifest itself on ThinkPad Models T410, T410i, T510, T510i, and W510.
Note: Customers with Edge 13, Edge 14, Edge 15, E30, E40, E50, L410, L412, L510, L512, SL410, SL510, and X100e systems still need to have at least the first firmware update. This can be checked in Power Manager, on the Battery Details tab. If this page shows the battery FRU number as one in the "Affected FRU Number" list below, the firmware update should be applied.

This page is a quick summary. Give me the full version.

This battery firmware update utility fixes an issue where some batteries indicate an incorrect full charge capacity value. Because of this error, the amount of energy available for use is artificially low, decreasing the amount of time the system can be used on battery. The fix is entirely contained in the battery firmware update; there is no need to replace any hardware for this problem.

Any of the affected battery FRU numbers below:

The battery firmware update requires that a supporting Power Management driver and BIOS are installed. Lenovo has bundled the necessary dependencies and the battery firmware update into a common package. During the update, the system may reboot, or be shut down.