Compaq nc8000 Lithium-ion battery technology: Getting the most from Smart Batt - Page 4

Warranty period HP provides a 12-month warranty for Li-Ion batteries. The warranty period is based upon the expectation that the battery will deliver 80% of its initial capacity after 300 cycles at low to moderate power loads. High power loads may cause a battery to reach 80% of initial capacity in less than the 12-month warranty period. Li-Ion batteries will continue to operate below the 80% capacity threshold; however, the capacity (run time) delivered between charges will continue to decrease. Table 1 summarizes FCC projections after one year based on 2 user profiles and various power loads. The first profile is for a mobile user who fully discharges and charges the battery almost every working day (300 cycles per year) in a normal environment. The second profile is for a stationary user who only cycles the battery once per week in a high-temperature environment, such as in a docking station. As shown in the table, the additional heat generated by running high power applications or by using a docking station accelerates the loss of capacity. Table 1. Full charge capacity projections after one year of use Power load (applications) Full charge capacity (% of initial capacity) after one year Mobile user Battery cycled daily (25ºC, 77ºF) Stationary user (with docking station) Battery cycled weekly (>35ºC, 95ºF) Low (word processing, Internet, e-mail) >80% 80% Moderate (wireless, spreadsheets, database management) 80% 70% High* (CAD, 3D games, DVDs, high LCD brightness) 60% *High power applications may also reduce the battery cycle life by as much as 25%. 50% 4