Running from external battery without charging internal one

alejandro-

macrumors newbie
Original poster
Jul 7, 2017
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Hello there!

First post here, hope someone can give me a hand on this. been googling around for a couple days without finding much information about it.

I saw a review of a power bank that can power the 2016/17 MBP and keep it from charging the internal battery while at it. It seems like an awesome thing since this would heavily increase the lifespan of the internal battery of MBP.

I wonder, does anyone know how this works? Is it something that gets activated automatically when the input voltage is 12v? Or maybe it is activated once the voltage falls to 9v?

On second hand, it is something the user can choose from somewhere in the OS while connected to an external power source?

All information on this will be very much apreciated!!! Thank you!!
 

New_Mac_Smell

macrumors 68000
Oct 17, 2016
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Pretty sure there's no manual way of not charging the battery.

If the internal battery is at 100% it would cut the charging circuit, otherwise it'll charge the battery. Plugging in an external battery is no different than plugging in any power source. Not sure why you'd want this either? If the battery is 70% and you're running it straight from the power source, that battery is still going to need to be charged up.

By careful on the external batteries though, not many if any are actually rated for the 15" and you can easily damage the computer. Look for good quality one's that officially say 'MBP 15/13"'.
 

ZapNZs

macrumors 68020
Jan 23, 2017
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I'd be interested to hear this as well - specifically, what methodology is employed to achieve this (and whether or not it is safe.) If this means the internal battery can be kept at roughly 50-75% capacity, that could prolong the service life of the battery tremendously. Sadly, the ability to program the battery to stop at a certain percentage/voltage is a feature sorely missed among consumer devices. If Apple just gave us the easy ability to terminate charging at a certain percentage, that would be so, so nice.

Do you have a link to this product?
 
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New_Mac_Smell

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Oct 17, 2016
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I'd be interested to hear this as well - specifically, what methodology is employed to achieve this (and whether or not it is safe.) If this means the internal battery can be kept at roughly 50-75% capacity, that could prolong the service life of the battery tremendously. Sadly, the ability to program the battery to stop at a certain percentage/voltage is a feature sorely missed among consumer devices. If Apple just gave us the easy ability to terminate charging at a certain percentage, that would be so, so nice.

Do you have a link to this product?
It is feasible with the USB-C technology I suppose, as the cable is transmitting data alongside power, it is capable of at least reading what kind of charger is connected. In terms of extending lifespan I don't think it makes a great deal of difference in the long run, you're talking lasting 4 years to 5 years. Most of the time you'll probably replace the computer long before the battery has issues.

Why don't they just make batteries 20% larger than their charge capacity? Wouldn't that be great, maybe they already do that?
 

Adamantoise

macrumors 6502a
Aug 1, 2011
891
112
Pretty sure there's no manual way of not charging the battery.

If the internal battery is at 100% it would cut the charging circuit, otherwise it'll charge the battery. Plugging in an external battery is no different than plugging in any power source. Not sure why you'd want this either? If the battery is 70% and you're running it straight from the power source, that battery is still going to need to be charged up.

By careful on the external batteries though, not many if any are actually rated for the 15" and you can easily damage the computer. Look for good quality one's that officially say 'MBP 15/13"'.
I second the bolded.

I don't think there's a way to bypass the circuitry that way. If you notice that your laptop isn't charging, it's probably just because the power draw from the laptop is equal to what the laptop is drawing from the battery.

According to the laptop, DC in is DC in, it doesn't care if it's from the Apple power adapter, an Anker power adapter, or an Aukey battery pack.
 

Lennyvalentin

macrumors 65816
Apr 25, 2011
1,429
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The travel magsafe power cord for older MBPs would power your laptop, but not charge the internal battery (because of power draw limitations from the proprietary connector the cord hooked into). That was somewhat of a special case though...

Unless there's an equivalent USB-C cable available (and suitable power connectors to plug it into), I don't think there's a way to power a MBP and not charge the battery, short of physically disconnecting the battery pack itself (a bit of a bother, especially if out and about...)
 
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alejandro-

macrumors newbie
Original poster
Jul 7, 2017
12
3
I'd be interested to hear this as well - specifically, what methodology is employed to achieve this (and whether or not it is safe.) If this means the internal battery can be kept at roughly 50-75% capacity, that could prolong the service life of the battery tremendously. Sadly, the ability to program the battery to stop at a certain percentage/voltage is a feature sorely missed among consumer devices. If Apple just gave us the easy ability to terminate charging at a certain percentage, that would be so, so nice.

Do you have a link to this product?
Yeah, check it out here at about 2:21s.
 

KGB7

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Jun 15, 2017
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Rockville, MD
Read their website.

P.s.
For half the price you can get bigger and probably better battery from Anker.
 
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Coco Nuts

macrumors member
Jan 1, 2016
35
10
On the older MacBooks, you can put a little piece of tape over the middle pin of the Magsafe charger. That way it powers the MacBook, but doesn't charge the battery. Pretty sweet!
 

alejandro-

macrumors newbie
Original poster
Jul 7, 2017
12
3
On the older MacBooks, you can put a little piece of tape over the middle pin of the Magsafe charger. That way it powers the MacBook, but doesn't charge the battery. Pretty sweet!
Nice! That is something I did not know! I wonder if there is any to be done like so in a usbc connector to achieve the same. Do you by any chance know if this "hack/trick" has a name? That might help the googling = )

Read their website.

P.s.
For half the price you can get bigger and probably better battery from Anker.
Thanks, that is the first thing that I did. From your remarks I realise the whole point of the thread is eluding you so perhaps reefer yourself to first post for clarification.
 

macintoshmac

macrumors 68040
May 13, 2010
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Do you really, really, really, one more really, need the battery life that way to go to such efforts to keep it for 1 more year? Why not buy a system without battery that runs on power only? That way, you save the battery 100% and do not go to such extreme lengths while doing it.
 
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KGB7

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Thanks, that is the first thing that I did. From your remarks I realise the whole point of the thread is eluding you so perhaps reefer yourself to first post for clarification.
What has eluded you, is that you cant use it with 2016/17 MacBook Pro.

The USB port on the battery box, puts out max of 10watts, which is only good for 12" MacBook during light use. Clearly stated on their site.

The main plug on the BatteryBox, is for older generation MacBooks that use MagSafe port. Which you clearly missed in the video as well. You can see that MacBook has more iO ports.

So I'll say it again. Read their website.
 

alejandro-

macrumors newbie
Original poster
Jul 7, 2017
12
3
What has eluded you, is that you cant use it with 2016/17 MacBook Pro.

The USB port on the battery box, puts out max of 10watts, which is only good for 12" MacBook during light use. Clearly stated on their site.

The main plug on the BatteryBox, is for older generation MacBooks that use MagSafe port. Which you clearly missed in the video as well. You can see that MacBook has more iO ports.

So I'll say it again. Read their website.
I see now I missinformed people on my first post out not re-reading my own post. Indeed it is for older MBPs though my interest was to identify how was it achieved to then perhaps get it to work on 2016/17s. Hope that explains it enough.

Do you really, really, really, one more really, need the battery life that way to go to such efforts to keep it for 1 more year? Why not buy a system without battery that runs on power only? That way, you save the battery 100% and do not go to such extreme lengths while doing it.
Its more about keeping it lasting to its full original endurance capacity for as long as possible.

On the older MacBooks, you can put a little piece of tape over the middle pin of the Magsafe charger. That way it powers the MacBook, but doesn't charge the battery. Pretty sweet!
After some forum search I came across this:
https://forums.macrumors.com/threads/program-to-disable-charging.1667538/
This is from a fellow trying to achieve this via software by using the kIOPMAssertionTypeInhibitCharging function from the IOKit library....thing is after some good old googling... apparently Apple removed this function from OS X after Yosemite update.

This feature seems to be one more of those that got lost in the road =)
 
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macintoshmac

macrumors 68040
May 13, 2010
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Its more about keeping it lasting to its full original endurance capacity for as long as possible.
To the point of taking extreme measures? Why don't you just use the machine as your normal workday/ work schedule allows you to? The batteries are not meant to be babied, they are meant to be used as needed. When on a desk, plug it. Using it connected to a monitor at home? Plug it. Connecting it to a monitor at work for presentation? Don't plug it. Heavy CPU/GPU usage at home? Plug it. Editing at work? Don't plug it. Like that.

There really is no rocket science to it. Plug it when you can, unplug it when you need to be off. Just one small thing - do not keep it in any one state for too long - that is, do not keep it plugged in for days on end, and do not run down the battery to the ground before charging back up. Anything between these two extremes will be just fine.
 

KGB7

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Jun 15, 2017
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Rockville, MD
To the point of taking extreme measures? Why don't you just use the machine as your normal workday/ work schedule allows you to? The batteries are not meant to be babied, they are meant to be used as needed. When on a desk, plug it. Using it connected to a monitor at home? Plug it. Connecting it to a monitor at work for presentation? Don't plug it. Heavy CPU/GPU usage at home? Plug it. Editing at work? Don't plug it. Like that.

There really is no rocket science to it. Plug it when you can, unplug it when you need to be off. Just one small thing - do not keep it in any one state for too long - that is, do not keep it plugged in for days on end, and do not run down the battery to the ground before charging back up. Anything between these two extremes will be just fine.
I thought this is a common sense.

But that's all you should be doing.
 
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