The life of your battery will vary depending on the product configuration, product model, applications loaded on the product, power management settings of the product, and the product features used by the customer. As with all batteries, the maximum capacity of your battery will decrease with time or use.
All rechargeable batteries gradually lose their capacity to hold a charge. The battery cycle life is the total number of charge cycles a battery supplies before it can no longer hold a useful amount of charge.
This loss in capacity (aging) is irreversible and cannot be restored. Gradually, less and less active material is available within each cell to electrochemically store a charge. Consequently, the battery provides less useable time to power the computer.
Lithium-ion (Li-ion) batteries typically have a lifespan of between 300 and 500 cycles. With moderate use, Lithium-ion batteries can be expected to deliver around 80% of their original capacity after 300 cycles or about one year of use (see graph above).
Note: The graph above illustrates 80% of original capacity after 300 cycles at an operating temperature between 77° Fand 104° F (25° C and 40° C). Higher operating temperatures can result in a 70% or more loss of capacity given the same number of cycles.