A number of Notebook users have contacted the call center with complaints related to the length of time that their battery charge lasts.  Generally the impression that the battery is not performing as it should is based on a comparison with other Notebook models, advertised specifications or the user's experience when the system was new.  There are a number of factors, completely unrelated to a system or battery problem, which will impact these comparisons.  In some cases the user may be able to apply configuration changes that will improve the battery performance. However, in many cases the customer's expectations are inconsistent with the realistic capabilities of the system and battery technologies and need to be adjusted.

How long a battery charge will last will vary based on the hardware configuration, the power management settings for the specific system, the software being used and the system activity level.  Memory, Hard Disk, Optical drive, display, fans, graphics controller and system processor all significantly impact the amount of power required which, in turn. affects the charge life of the battery.  

Power management refers to a number of system settings which provide the user with an opportunity to control system performance levels in a manner that will reduce power consumption and prolong the battery charge life.  These settings include maximum CPU performance, display brightness, idle device power down frequency, system suspend or hibernate frequency and fan operation.  Through these settings a user has the ability to balance battery charge life with system performance in a way that is best suited for the their situation and system requirements.

One additional factor in battery performance is the fact that a battery will lose some charge capacity as it goes through charge cycles.  A battery that has been recharged a hundred times will provide a noticeably shorter charge capacity then it did when it was new.  The industry generally considers a lithium battery to be good for 500 charge cycles, however, the charge life may be reduced by 30% to 40% at that point.

The final point to be considered in discussing battery performance is the purpose and meaning of Battery Performance Ratings or specifications.  Computer manufacturers have standardized on a small number of bench marking applications to rate battery performance.  There are significant differences in both system and battery design which affect power efficiencies while the system is in an idle or low performance operating modes as well as in high performance operation.  The largest opportunity for battery performance improvement is related to idle or low performance mode power efficiency.  To provide meaningful comparison between products the bench marking applications will cycle through the entire range of operating levels and will maintain the system in idle or low power conditions for longer periods then would generally occur during normal system usage.  The battery rating is often represented in the number of hours the battery lasted under the consistent operating conditions controlled by the bench mark test and is used as the battery performance spec by the manufacturers.  While this does provide a valid comparison between models it does not, and is not intended to represent the specific charge life the user will experience in day to day use of the system.