What are the signs of performance degradation as the battery ages?

The performance degradation of the battery after aging mainly includes the following points:

1. **Decrease in capacity**: After aging, the active material inside the battery is gradually depleted, resulting in the battery capacity not being able to be restored, the actual use time is reduced, and more frequent charging may be required.
2. **Self-discharge accelerated**: After battery aging, the activity of electrode materials is weakened, resulting in a slower rate of chemical reaction inside the battery, which accelerates the self-discharge rate of the battery.
3. **Voltage drop**: After aging, the internal resistance of the battery will increase, resulting in a drop in the voltage generated by the battery during operation, which may affect the weakened range of the device or the inability to work properly.
4. **Changes in charging and discharging platform**: After aging, the charging and discharging platform of the battery will move in a lower direction, resulting in over-charging and over-discharging of the battery during charging and discharging, which affects the use of the battery.
5. **Increased temperature fluctuations**: After battery aging, the internal chemical reaction rate slows down, resulting in a reduction in the heat generated by the battery in the working process, and more sensitive to changes in the temperature of the external environment, which is prone to excessive temperature fluctuations.

In short, battery aging will lead to the emergence of a variety of symptoms, including decreased capacity, accelerated self-discharge, voltage drop, charging and discharging platform changes, and increased temperature fluctuations.
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