Battery percentage jumps 2% randomly when charging

I don't use my phone much at all. It's down the 94% after 6 months, right on schedule according to Apple. Yes, I know exactly what is running on the phone.

Lucky you. We answer multiple questions every day from users complaining that their Battery Health declines about 1% a month.

We also had a user recently whose phone was at 95% after 7-8 months.......pretty darn good......then the Battery Health dropped 5% the next month.

Ashton0814 wrote:

Yes I understand but I also do go to most extremes to keep my phone in low power mode not using 5G when most definitely capable of doing so. And making sure that I try to not use my iPhone when it’s charging or intensely using it, I take its case off and make sure it’s in a cool environment not on a table ect.

There is very little you can really do to prevent loss of battery capacity. It will happen. Batteries are consumables. Physics always wins.

Batteries are relatively cheap to replace. My advice would be to stop trying to micromanage it, use your phone and enjoy it and replace the battery when it stops being usable (if you're not at a point to replace your phone).

See also:

When to charge your iPhone or iPad - Apple Community

Nothing at all wrong with your battery. If the phone was 6 months old, you would expect Battery Health to be about 94%, since this number will decline an average of about 1% a month.

99% at 6 months would be far above average performance, so you can pat yourself on the back for your amazingly good luck with your battery.

The battery percentage display during charging is an approximation based on activity that is going on in the background during charging. If the background activity slows down, then the percentage can jump a few points. Nothing to be concerned about.

Frankly, I'm still wondering how you are getting such good performance from your battery. It must have been the best of the batch during manufacturing. After 12 months, most of us see a Battery Health of 88-90%. Let's hope the law of averages does not catch up for you and your phone.

Remember that your iPhone is a mass produced device, and the components used for battery health measurement are not individually calibrated, and battery condition is notoriously difficult to measure. The estimate may also be influenced by device and battery temperature from moment to moment. I would not expect the battery condition estimate shown on screen to be better than about +/-5%

Also remember the battery condition starts as an analog measurement and is then converted to a digital value for display. It is generally accepted that any digital numeric display will have +/- 1 unit uncertainty in the least significant digit just from the analog-digital conversion process.

Hmm, my 10-month old iPhone SE (3rd Gen)‘s battery health is 99%.

It depends what one uses it for and how much.

Battery is charged when necessary.