Battery packs provide power to portable computer systems, e.g., laptops, notebooks, palmtops, etc. Battery packs may be used to provide power during periods when main power, such as alternating current (AC) power, may be unavailable. In many instances, battery packs are retained within the connected computer system, e.g., inserted into a cavity in the portable computer system.
During and after use, e.g., charging and discharging, battery packs generate heat which may decrease performance and reliability of the battery packs.
FIG. 1 depicts a side section schematic diagram of a portion of a portable computer system 100 comprising a computer housing 101 forming a cavity 102 for receiving a battery pack 104. Battery pack 104 comprises a housing 106, e.g., a plastic shell, enclosing a battery cell 108, e.g., an electrochemical cell. For orientation purposes, an upper surface of housing 106 is the portion closest to the top of the page and a lower surface is the portion closest to the bottom of the page. Heat generated by battery pack 104 generally rises from the bottom of the page toward the top of the page. Battery cell 108 is positioned in battery pack 104 and prevented from moving within the pack through the application of four positioning members 110, e.g., glue or silicone portions, between the cell and the pack. A pair of electrodes 112 extend from battery cell 108 to an outer surface of housing 106 in order to contact a pair of contacts 114 in cavity 102 to transfer an electric charge to/from the battery cell. An air gap 116 separates battery cell 108 from housing 106 and acts as an insulator to retain heat within housing 106. An additional air gap is formed between cavity 102 walls and battery pack 104 to facilitate user removal.