1. Li-Ion battery cells suffer gradual, irreversible capacity loss with each discharge-charge cycle. Such aging occurs more rapidly as temperature and discharge loads increase.
2. The self-discharge rate of a Li-Ion battery is higher if the battery is left in an unpowered notebook.
During prolonged storage or non-use, the battery charge will decrease below its recommended low-voltage level.
3. Leaving the battery in a depleted condition for an extended period accelerates the decrease in full charge capacity. Leaving the battery at a high level of charge in a high-temperature environment for extended periods (for example, running a notebook computer in a docking station under a heavy load) also accelerates the loss of capacity.
4. Running high-end applications using the battery accelerates the loss of capacity. For example, playing 3D games lowers full charge capacity faster than using word processing applications.