For five years I charged my old cell phone in the other room
Then when charged , I'd place it on the base of a desk lamp
in another room.

My new phone charges to 80%,
Then stops charging to prohibit some kinda
damage , that I know nothing about.


But ! I also set the new cell phone on the same
L.e.d
Desk lamp base,
It has charged the cell phone up to 100 %
charge. Not using cords or pluds or outlets.

It just charges all by itself


What's up with that ?

My new(ish) phone has a setting on it to limit the charge to some specified cutoff point. 90% is what was recommended. You can change that limit point, or disable it so it will always charge to 100%, somewhere in the settings.

Not sure what the other thing is about. Some phones (not mine) can charge without being plugged in. I think it's a wifi signal that does it, but I'm not sure. Maybe your desk lamp emits a wifi signal, or something near it does? I'm guessing that using the wifi charging somehow bypasses the charge limit setting.

Settings > Battery > Optimized battery charging.

"To reduce battery aging, iPhone learns from your daily charging routine so it can wait to finish charging past 80% until you need to use it"


I believe this works by letting the battery cool down before final topping off. Heat is the enemy of rechargeable batteries. But thats just my guessing. I figure Apple knows more about best practices when it comes to charging a battery.

I leave it on... you can turn it off by the path I posted above.
If I look at my phone in the middle of the night, it says it's 80%... but by morning it says 100.

Keep it at 80%. It will preserve your battery’s life. When you travel or have an important schedule, change it to 100%. You also want to recharge around 20% too.

Does your desk lamp have a specific spot to set a phone? If yes, then perhaps that spot is a wireless charger.

Wireless chargers don't use WiFi or any other signal to send electricity through the air. Instead, they use magnetic fields to generate electricity which has been around for almost 200 years.

quote:

Originally posted by trapper189:
Does your desk lamp have a specific spot to set a phone? If yes, then perhaps that spot is a wireless charger.

Wireless chargers don't use WiFi or any other signal to send electricity through the air. Instead, they use magnetic fields to generate electricity which has been around for almost 200 years.

I have one of those chargers on my end table and my wife's new Pathfinder has a wireless phone charger on the console .
They even make them to charge Electric Vehicles now .

I’m not convinced the charge limiting thing is beneficial. I fully charge the phone nightly and after a year and a half the battery is at 92% capacity. But the phone is also generally down to like 20% each night so it does get used. iPhone 16 Pro Max, had since September 2024.

No ,the desk lamp base does not have a dedicated
"cell phone" spot.

My settings says 80% charge is on.

Then there is no way that your phone is being charged from 80% to 100% when it is not plugged in. Something else is afoot.

quote:

Originally posted by trapper189:
Wireless chargers don't use WiFi or any other signal to send electricity through the air. Instead, they use magnetic fields to generate electricity which has been around for almost 200 years.

Guess I misspoke then, thanks for the correction.

Afoot , amiss , my thoughts as well .
It's happened twice now.

The charging stops at 80%,

Says right on the screen .
I will try not setting it on the desk lamp , next time

quote:

Originally posted by bendable:
Afoot , amiss , my thoughts as well .
It's happened twice now.

The charging stops at 80%,

Says right on the screen .
I will try not setting it on the desk lamp , next time

The 80% hard charging limit, whose settings you have found with the help of others above, was rolled out in 2023 with the iPhone 15 launch and can be turned on or off. It is to help keep the maximum battery capacity higher over the lifetime of the phone.

With that being said Apple also mentions “Even when enabled, the 80% limit will occasionally allow the phone to charge to 100% to maintain accurate battery percentage estimates.” So what you are seeing is normal. I notice it from time to time on my phone and iPad. Nether your lamp nor your phone are possessed.

quote:

Originally posted by cparktd:
Settings > Battery > Optimized battery charging.

"To reduce battery aging, iPhone learns from your daily charging routine so it can wait to finish charging past 80% until you need to use it"

Yep, first noticed it on my new iWatch that it wasn't going past 80%, a little googlization and searching it said just that about how Apple has optimized the battery charging.

Interesting that GM and most EV's do the same, they instruct you to charge to 80% only unless you are going on a trip or will need extra range for that week. It reduces the time to charge, the cost, and helps with battery life.

Motorola android cell.

I didn't set on the lamp base and it didn't charge over 80%.

Thanks for the info.
Glad to hear I am not going nuts.
( All the way ,anyway)

My S20 stops at 85%.

Set it on the lamp base again and see if it charges.

Okie dokie