Does Macbook Pro charging profile depends on electricity grid?

The questions might sound silly at first sight, but let me share my observations so far:

  • I’m in the U.S. right now where I use the charger I got from IT and I see that my MPB charges slowly. It says the battery is 51% full and will take another ~16 hours to fully charge
  • In my workplace I experience that too the charging stops around 80% and does not matter which plug I use
  • In the hotel with the same charger the same MBP charges two-three times faster and does not stop at 80%
  • home, which is Hungary with 240V electricity grid, reaching the fully charged state takes 2-3 hours (does not matter if I recompile my app in every other minute) and never stops at 80%)
  • I brought the charger came with MBP and the phenomenon is the same

Since I’m not an electricity engineer I don’t know whether voltage matters in charging or not. In the U.S. there is 120v, but in EU we use 240V. Differences in Amper, I’m not aware of. In the EU, we use 20A or more fuses.

Is it possible the difference I experience is due to something default Apple magic in MBP?

How can I fix a charging problem on Moto G5 Plus?

A Moto G5 Plus device (Android 8.1.0) was charging and performing normally with a healthy battery response.

One morning, instead of being at 100% (expected after charging all night), the phone reported 61% (unexpected after charging all night). This was with the same charger I always use, which is the one that came with the phone.

Settings > Battery reports that the phone is charging, but the reported charging percent does not increase at all. So if I plug it in at night with 42%, it says 42% again in the morning.

The device is discharging at a normal rate. In other words, given a certain level of charge, and not plugged-in, the battery lasts a normal/long/expected amount of time (many hours with just a few battery percentage points down).

Theory of Cause: Not Slow Decline

Because of the suddenness and severity of the difference between the former and current observations, the likelihood of this being attributable to simple wear on the battery seems unlikely. That leaves a software problem as a more likely cause.

First Action Tried: Clear Cache

I read that clearing cache could help, so I tried that by doing the following:

  1. Press Power and Volume Down and hold a long time until you see the screen have a “weird menu” thing
  2. Press and release Volume Down until you see Recovery Mode. You’ll see an Android on it’s back with a triangle/exclamation mark.
  3. Hold the Power button and then press and release Volume Up then release all buttons. You should see a list of actions.
  4. Use Volume Down to scroll to wipe cache partition, then press and release Power to activate.
  5. Use Volume Down to scroll to reboot system now, then press and release Power to reboot.

First Action Result: No Change

Symptoms seem to persist as before: while plugged in and while the phone reports that it is charging, the percent reported does not increase.


Because I’m an Android developer, I have access to Logcat in Android Studio. I see this reported periodically in the logs:


This is with the USB cable is plugged into a computer, of course.

The POWER_SUPPLY_VOLTAGE_NOW value ranges from 4394xxx up to 4397xxx, indicating the PC is offering a slightly different voltage over time or that the phone reads the voltage slightly different (0.07%), which seems normal.

The POWER_SUPPLY_CURRENT_NOW value ranges from 91xxx to 354xxx, but mostly is around 112xxx. This variability probably has to do with how much activity is going on in the phone and whether the screen is on. This also seems normal.

The POWER_SUPPLY_TEMP value started at 317 (when I first started logging) to 275 (after an hour). I’m not sure what this change (-13%) means, if anything. Probably because the screen was on earlier in the log and mostly off later in the log.

The rest of the fields seem not to be changing over time.

Second Action Tried: Lower Temperature

Knowing that some phones have had issues with getting too hot while charging, I thought that maybe this was an aggressive safety thing that was being incorrectly triggered. The phone was NOT getting even slightly warm when charging, but I thought I’d put it in the freezer while being charged. I put it in the freezer for an hour or two with the cord attached.

Second Action Result: Improved, But Not Resolved

After charging the phone in the freezer, the phone did show a higher battery percent. The reported percent was erratic, though. It jumped around from the 90% range to the 30% range. The reported percentage changed as I plugged it into the charger and removed it from the charger.

Third Action Tried: Plugged in While Off

To reduce the number of programs active during charging, I powered the phone off and left it connected to the PC. Based on the PC’s reaction to the USB connection, I can tell that there’s still some kind of processing going on in the device, but I thought it might make a difference. The device reported 32% at the start. It indicated that the device was charging.

Third Action Result: Same Symptoms

After leaving the device connected for an hour, it still reported 32%, so the main symptom of this question persisted, even if the charging activity was undertaken while the device was “powered off”.


Is there an action or set of actions I can take to get the device to resume normal charging behavior?

How to limit charging to 60%

My UleFone Armor 2 has 4700 mAh, but I would like to limit it to 60% to reduce battery ag**g. The battery in more and more phones is not user-replaceable thanks to Apple’s toxic influence on the mobile phone market, and I am worried that a factory/service battery replacement might affect water resistance negatively.

How can I limit the charging to 60%? (But not limiting charging speed. I love fast charging.)

Lenovo ThinkPads have a built-in feature that does this, called “battery preservation mode”.

Where can i locate the file responsible for activating charging in my jellybean and kitkat android?

I have Tecno H3 running android 4.4.2 kitkat and Tecno P5 running android 4.2.2 jellybean. I want to completely disable charging at 85% and re-enable it at 50% without rebooting the phone. So i went to /sys/class/power_supply/ac/online and changed the permission from 444 to 755. But when i connected the charger, i edited the content of the file “online” from “1” to “0” so as to disable charging even when the charger is connected the phone reboots itself instead of disabling charging? What is the solution please because the “BatteryChargeLimit” app didnt work as it was designed for lollipop(5.1) and above. Is there any shell script that can do that for me in Jellybean and kitkat please? Or how can i manually do it?

phone running speed when charging

I have noticed that when my phone is charging, it is running noticeably faster than when it’s running on battery, frames are smoother, etc. Is there a way to force the phone to run as if it is charging. I think this might be related to processor speed but I was not able to find any options in developer settings

Does connecting an android device via usb to a PC pose a risk if charging is selected?

If an android device has some something malicious on it that can also target/affect PCs. And that device is connected to a PC via USB, by default it automatically chooses to start charging.

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Is there any risk that anything could be transferred to the PC? As in, is it possible for a split second before it chooses the “Charging” setting that it allows some data transfer to the computer?

At work we are warned not to connect and USB devices to our computers but a colleague had told me that they charge their phone (Google Pixel – Android 9 Pie) via USB and since charging is chosen by default it’s fine. While this seems totally logical wasn’t sure if it was exactly true?

Power on when charging but only when battery level is greater than 20%

I have recently tried to fit a tablet into my car and I came across a problem with waking up the device without using the power button.
My solution is to boot the device whenever it is charging, but I have noticed that when the battery level is at 0%, the device boots and then immediately shuts down.
I have used this adb option to trigger this behavior:

fastboot oem off-mode-charge 0 

However this boots the phone without checking the battery level and as I said –
if the battery is dead, the phone (or rather a tablet- Nexus 7 2012) turns off immediately –
it drains the battery faster that I’m able to charge it. Is there any way to make the tablet boot only if the battery level is greater than, say, 20%?

Which pins to solder to make charging faster

I need to solder charging wires directly to my motherboard in a Nexus 7
2012- I put it into my car and I just don’t have enough space for the USB plug.
So here is what I have done now:
enter image description here

The brown wire is +5V and I will solder the GND wire somewhere,
but the real question is, which pins should I short?
I’ve read shorting D+ and D- can help with my slow charging but I have no idea which pins these are on the picture. Can someone tell me which ones to short with a solder blob?
Right now the connection I made draws 0.8A of current which is not enough to keep the device alive (battery is drained faster than it is charged).
Power supply is not the limiting factor since I’m using a lab power supply which can supply up to 3 amps at 30V.
I guess the pins I have to short are two of the five pins to the left of the port (on the picture), but which?
Or maybe there is a different way to increase the charging current?

Should readying an action to set a brace weapon dissuade an intelligent enemy from charging?

The rules about readying a weapon against a charge states :

You can ready weapons with the brace feature, setting them to receive charges. A readied weapon of this type deals double damage if you score a hit with it against a charging character.

I’m wondering if this kind of readied actions should be visible or not during the combat and then possibly modifying the actions some characters or enemies would make ?

Here for the example, the PC group progress in a dungeon corridor, the fighter with a brace weapon opening the way. At that moment they face a hostile group of bandits. The fight begins and the fighter being first at the initiative roll decides to set its brace weapon as a readied action. If they had been first at the initiative roll, the bandits would have charge the fighter. Now that the fighter prepares to receive a charge, if the readied action is visible to them, it would obviously be a less appealing idea and they would engage him with a move action instead of charging.

The other examples I found on this subject are based with generic creatures which don’t really bother of the ennemy tactics, but in this situation, should the bandits deny the fact that the fighter has readied its action and charge him anyway or should they notice this action and react accordingly to avoid impale themselves on the weapon ?

Force charging a iPad 4 battery

I recently found my iPad — it’s a 4th gen and it hasn’t been used in a long time. When I plug the cable it just keeps rebooting and not turn on. I tried so much pressing home and power buttons and other solutions too nothing didn’t work. Finally I took a risk and dismantled it and separated the battery. I tried to charge the battery from there so the logic board won’t drain the battery before it charges. I have done it to a different iPad but it didn’t seemed to work this time I haven’t assembled it so if there are any solutions suggested that would be really helpful.