iPad What’s going on with my battery?

[RudolphRedNose]

Hi all,

I’m wondering if anyone would be able to explain this weird battery charging inconsistency.

I took my iPad (9th Gen) off charge and turned off around 1840 yesterday evening, with 95% charge. When I turned it on this afternoon, just after 1500, I noticed the battery was at 100%.
I know it was 95% last night because I turned on the screen to check the power level. It was charging and then it briefly said ‘not charging’, and I had to take the cable out and plug it back in. It was charging again, but I needed to go out so I unplugged it with 95% and turned off the iPad.

When I check the battery statistics, it looks as though it has been charging all night (its been in my backpack).

I don’t really use the iPad that often, I don’t have an iPhone, and I also don’t often pay attention to the battery. I just happened to notice this, and thought it was odd. Maybe it’s a faulty battery. What’s your thoughts?

 

[BanjoDudeAhoy]

That seems a bit odd, yeah.
Even if it had been connected to a power source, I would guess it would display green bars through that transparent green area. And for just being off, it should be empty.

I will say, though, I've seen a bunch of not quite accurate graphs in settings on iPad since the release of iPadOS 17, so I wouldn't rule out a bug, either.

If it was mine, I'd probably just keep and eye on it and if there are any other weird things happening, take it to an Apple Store to have them check it out. Or get on a call with them and explain what's happening if the Apple Store visit is not an option.

 

[shinyleaf]

This is totally normal. The battery graph can’t track charging state when the iPad is turned off, so it always tries to fill in the gap. My guess you turned it off first before unplugging?

Second, the battery meter on all phones and tablets aren’t really 100% accurate. It’s an approximation because it’s not physically possible to measure a lithium battery state of charge with 100% accuracy. There’s about a 5% wide margin of error. The operating system on phones and tablet and laptops typically smoothes out this margin and so users aren’t distressed over it.

 

[RudolphRedNose]

Actually, I unplugged it, then turned it off.

I figured that as Apple Hardware and Software is supposed to work so well together, the chance of discrepancies as much as 5% would be avoided. Especially when they battery is fairly new. It probably has less than 20 charge cycles and is probably around 7/8 months old. I sometimes experience this with my Pixel though. Turn it off and on, and the battery percentage has change a few percent.

 

[Pixels7]

Hi all,

I’m wondering if anyone would be able to explain this weird battery charging inconsistency.

I took my iPad (9th Gen) off charge and turned off around 1840 yesterday evening, with 95% charge. When I turned it on this afternoon, just after 1500, I noticed the battery was at 100%.
I know it was 95% last night because I turned on the screen to check the power level. It was charging and then it briefly said ‘not charging’, and I had to take the cable out and plug it back in. It was charging again, but I needed to go out so I unplugged it with 95% and turned off the iPad.

When I check the battery statistics, it looks as though it has been charging all night (its been in my backpack).

I don’t really use the iPad that often, I don’t have an iPhone, and I also don’t often pay attention to the battery. I just happened to notice this, and thought it was odd. Maybe it’s a faulty battery. What’s your thoughts?

I have such big gaps in my graphs since iPadOS 16. Also my battery percentage jumps too when I unplug it from the charger or when I reboot. Apple said it’s an iPadOS 16 bug, so I guess it’s still not fixed, because I see more and more of such weird battery graphs. When I keep my iPad on WiFi 24/7 then these gaps in the stats don’t happen. But when I reboot the battery percentage jumps still.

Also my iPhone and iPad show different percentages on the lock screen vs in the upper right corner after charging.

 

[MacCheetah3]

This \/ is true:

Second, the battery meter on all phones and tablets aren’t really 100% accurate. It’s an approximation because it’s not physically possible to measure a lithium battery state of charge with 100% accuracy.

BU-603: How to Calibrate a “Smart” Battery

BU meta description needed...

batteryuniversity.com

Battery Calibration - iFixit Support

All newly-installed smart batteries should be calibrated as soon as possible. This helps your system get an accurate reading on the battery’s state of charge. W

help.ifixit.com

Nonetheless, there’s more to the story.. Foremost:

Batteries - Why Lithium-ion?

Learn why Apple rechargeable lithium-based technology provides the best performance for your iPhone, iPad, iPod, and MacBook.

www.apple.com

Beyond the 80% charge rate step down, there’s an overcharging prevention sub-cycle — I can’t find the source (beyond my observations) at the moment in part because Apple has changed their battery-related knowledge/support article many times over the years.

When an iDevice, MacBook, etc battery reaches the 100% (reported to the user — there are margins) and remains plugged in, the power/system management controller will stop charging, allow the battery charge state to lower until ~95%, begin trickle charging again, and repeat this until he device is unplugged. During this sub-cycle, in most instances, the battery meter will display 100% the entire time. In other words, you powering off and on the iPad probably caused iPadOS to update the reported charge — but again, the charge fluctuates and it’s all best guesstimate at the moment anyway.

Some other helpful/related information/articles:

Avoid extreme ambient temperatures.​

Your device is designed to perform well in a wide range of ambient temperatures, with 62° to 72° F (16° to 22° C) as the ideal comfort zone. It’s especially important to avoid exposing your device to ambient temperatures higher than 95° F (35° C), which can permanently damage battery capacity. That is, your battery won’t power your device as long on a given charge. Charging the device in high ambient temperatures can damage it further. Software may limit charging above 80% when the recommended battery temperatures are exceeded. Even storing a battery in a hot environment can damage it irreversibly. When using your device in a very cold environment, you may notice a decrease in battery life, but this condition is temporary. Once the battery’s temperature returns to its normal operating range, its performance will return to normal as well.

iPhone, iPad, iPod, and Apple Watch Comfort Zone​

32° F
95° F
Too ColdRoom TemperatureToo Hot
iPhone, iPad, iPod, and Apple Watch work best at 32° to 95° F (0° to 35° C) ambient temperatures. Storage temperature: -4° to 113° F (-20° to 45° C).

MacBook Comfort Zone​

50° F
95° F
Too ColdRoom TemperatureToo Hot
MacBook works best at 50° to 95° F (10° to 35° C) ambient temperatures. Storage temperature: -4° to 113° F (-20° to 45° C).

Remove certain cases during charging.​

Charging your device when it’s inside certain styles of cases may generate excess heat, which can affect battery capacity. If you notice that your device gets hot when you charge it, take it out of its case first.

Store it half-charged when you store it long term.​

If you want to store your device long term, two key factors will affect the overall health of your battery: the environmental temperature and the percentage of charge on the battery when it’s powered down for storage. Therefore, we recommend the following:

• Do not fully charge or fully discharge your device’s battery — charge it to around 50%. If you store a device when its battery is fully discharged, the battery could fall into a deep discharge state, which renders it incapable of holding a charge. Conversely, if you store it fully charged for an extended period of time, the battery may lose some capacity, leading to shorter battery life.
• Power down the device to avoid additional battery use.
• Place your device in a cool, moisture-free environment that’s less than 90° F (32° C).
• If you plan to store your device for longer than six months, charge it to 50% every six months.

Depending on how long you store your device, it may be in a low-battery state when you remove it from long-term storage. After it’s removed from storage, it may require 20 minutes of charging with the original adapter before you can use it.

Batteries - Maximizing Performance

Maximize the life and lifespan of the rechargeable lithium-ion batteries in your MacBook, iPod, iPhone, and iPad.

www.apple.com

iPhone Battery and Performance - Apple Support

Understand iPhone performance and its relation to your battery.

support.apple.com