Why is my lenovo yoga c640 13iml degrades gradually?

The Lenovo battery may need to be recharged more often to get the expected level of performance. This may indicate that the battery capacity has decreased. Capacity is the length of time the system can run on a fully charged battery. 

It is normal for all batteries to lose some capacity over time. Each time you discharge and recharge your battery, a very small amount of this capacity is lost. Run Battery Gauge Reset under Energy Management or OneKey Optimizer to test the battery runtime.

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    Price:112 NZD
    Free shipping: Yes
    Voltage: 7.68V
    Capacity: 7820mAh (60Wh)
    Battery cells: 4-cell
    Chemical: Li-ion
    Battery Color: black
    Condition: new original battery
    Warranty: 9 months
    Shipping time: 7-15 business days
    Shipping to worldwide: Yes
    
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