Matsushita demonstrated at the Intel Developer Forum (http://www.intel.com/idf/) what's in store for next-generation long-life batteries. While conventional lithium-ion batteries offer about 300 to 400 watt-hours of power per liter (Wh/l), the prototype with a cylindrical cell form demoed at the exhibit achieves an effective energy density of 620 Wh/l. Matsushita's ultimate goal is to power notebooks for thirteen hours at continuous use. Thirteen hours, that should be enough to check your e-mails and perhaps a bit more.

[via Tech-On (http://techon.nikkeibp.co.jp/english/NEWS_EN/20050825/107913/?ST=english)]