How to increase my battery health

Battery Health & Performance 

The battery health of your iPhone cannot be increased. iPhone batteries, like all rechargeable batteries, are consumable components that become less effective as they age. You should change out the battery once your Battery Health reaches below 80% which will take over 2 years to reach under normal usage. Until then enjoy your iPhone.

Here is some more reading on an iPhone battery and its performance ➔ iPhone Battery and Performance - Apple Support

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