5 Minimizing battery fatigue

When a rechargeable battery is exposed to multiple charge and discharge cycles, its ability to power the system degrades, which can negatively affect its performance and run time. In order to maximize the lifetime of both the battery and the system, it is important to design the IC to limit the overall cycle count of the battery.

Figure 3 shows that the cell capacity of a Li-ion battery decreases as the number of recharge cycles increases. Designing a power path battery-charging IC enables you to maximize its lifetime by shutting off the battery FET – powering the system directly from the adapter and preventing the system from using the battery for power eliminates the need to discharge and recharge the battery. With power path, you can choose to power the system with only the adapter if the adapter is present, which reduces the number of recharge cycles on the battery and maximizes its lifetime.

Figure 3 Li-ion cell capacity vs. number of recharge cycles.