Battery health issues.

All rechargeable batteries are consumable components that become less effective as they chemically age.

Recent software updates can accelerate that process by adding features that consume more power.

As lithium-ion batteries chemically age, the amount of charge they can hold diminishes, resulting in shorter amounts of time before a device needs to be recharged.

Apple won’t replace the battery until it reaches 80% capacity.

Battery Performance Tips:

• iPhone Battery and Performance.
• Check battery health and usage.
• Optimized Battery Charging.
• Maximizing Battery Life.
• Use Low Power Mode.
• About battery usage.
• Show battery percentage.

Need more help?

• Call 1-800-APLCARE. 📞
• International Support. 🌐
• Contact Apple Support. 📝
• Live chat using Messages. 💬

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How I can keep my battery Health 100 percentage, please advice

On a new phone.....or a phone that has just had the battery replaced.....the Battery Health / Maximum Capacity will be 100%. That number will only decline as time moves forward. The Max Capacity will never increase.

On average, the Mac Capacity will decline about 1% a month. That's an average. Some months it might not decline at all, and other months it might drop 2%. This is normal and expected.

So, after a year of use, the Max Capacity might be 88%-90%.

You should expect the battery to last approximately 2 years before it needs to be replaced again.