A single charge of batteries allowing the laptop to run for 24 hours? Sounds impossible, and its often also called as the Holy Grail of notebook computing but HP claims to have broken the barrier. HP did this with the EliteBook 6930p using the optional ultra-capacity battery.

Requires separately purchased Ultra Capacity Battery and customer download of the latest Intel graphics driver and HP BIOS. Notebook must be configured with optional Intel 80 GB SSD drive and HP Illumi-Lite LED Display (planned to be available October 2008) and requires Microsoft Windows XP operating system. Battery life will vary depending on the product model, configuration, loaded applications, features, and power management settings. The maximum capacity of the battery will decrease with time and usage.

The 12 cell battery costs USD $189.

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