In a new patent Apple application uncovered by Apple Insider, Apple aims to improve battery life by including multiple "jelly rolls" into a single pouch.
Jelly rolls (Swiss rolls), are typically found in your standard cylindrical rechargeable AA D batteries. Anode and cathode material is laid down and divided by a separator, then rolled up into a hollow cylinder in the design.
Apple's patent application "Battery with Multiple Jelly Rolls in a single Pouch," looks to improve current lithium batteries using this same technique. Typcial lithium batteries are are so well liked by laptop and mobile device makers because the battery cells are packaged in small flexible pouches and can be shoved in the tiniest of devices. However, their packaging efficiency is usually between 90 and 95%, leaving extra space. What Apple is attempting to do in their patent application is eliminate this unused space.
The use and placement of multiple jelly rolls of different lengths and thicknesses within a pouch may allow the creation of a custom battery cell that maximizes the use of free space within a portable electronic device and provides greater capacity, packing efficiency, and/or voltage than battery cells that contain only one jelly roll per pouch. - Apple Patent 20110183169