Battery keeps draining when powered down for days

[OneWonders]

This a Mac Book Pro 15 in 2018 model 15.1 running Sonoma 14.7.2. I bought this used 6 mo ago. Right from the start the battery would drain down to nothing if left unplugged for a week to 10 days Then it was using macOS 12 then 13 and now 14. and has had the same problem no matter what OS. I've had many MBPs and MBAs never encountered this. Wondering if you gentlemen would have a suggestion as to what I could do to solve this. I know, leave it charging. Right? Yes I know, there is still something not right. Maybe battery is defective or some process slowly draining power even though it is off. Not found any similar posts about this problem. There should no reason it couldn't be left a few days without looosing half its charge. And I'm sure this is probably aging the battery prematurely as it has gone to zero several times.
I am Grateful for this wonderful forum and read it regularly
Thanks for any help
Paul

 

[Randy B. Singer]

It's true that every time that you let a lithium battery discharge to 100%, it unrecoverably degrades the battery some.

In any case, your battery is about 6 to 7 years old. That usually means that a laptop's battery is well past the end of it's expected life anyway.

You can use this free utility to check your battery's status:

CoconutBattery (free)
http://www.coconut-flavour.com/coconutbattery/
If your battery's capacity is at or below about 80%, it's done.

There are lots of laptop battery manufacturers. I tend to feel that the best value laptop batteries come from Egoway. They can up to to a tenth the price of an OEM battery, with good performance and life. You can get one from Amazon.
https://www.amazon.com/EGOWAY-A1953-Battery-Replacement-MacBook/dp/B09J4RBBJD/ref=sr_1_1

Lost of folks instead swear by Xtend batteries:
https://www.laptopbatteryexpress.com/Apple-laptop-batteries-s/10.htm

You can find the instructions for replacing your laptop's battery here:
https://www.ifixit.com/Device/MacBook_Pro_15"_Touch_Bar_2018

 

[OneWonders]

Thanks for the reply Randy. Yes I have been monitoring the battery condition with CoconutBattery. I have used the app. for many years now on various MBPs That's why this problem seems so unusual with a slow steady drain at an almost predictable percentage rate every day. I wouldn't think a battery would fail like that. It states the battery condition is Good with only 188 charging cycles. Also I did reset SMC a couple months ago. Perhaps I should try that again. Thanks for leads on replacements if that is the answer for this.

Thank you
Paul

 

[Raz0rEdge]

Having the battery train when the MBP is asleep is one thing, but its fully powered off, there will be a small battery drain over an extended period of time (months or years) as somethings like the RTC (real-time clock) and other hardware continue to tick away. However their battery draw is so minimal that you wouldn't notice any difference across a few days.

 

[OneWonders]

I agree Ashwin, I have a heavlly used 2009 white Mac book with several hundred cycles on the original battery. I use this only occasionally now. At times it will sit powered down for over a month and only looses a small faction of the charge. Other MacBooks have been similar in my experience. Batteries don't seem to fail like this. So with this machine if I replace the battery will I have the same problem? Perhaps that is the only to know? My guess is that it's not completely powering down. I usually shut down from the apple menu. when it shuts down in a few seconds, I close the lid. Can this be wrong?
Thanks anyway
Paul

 

[MacInWin]

when it shuts down in a few seconds, I close the lid. Can this be wrong?

Could be, depending on how many seconds "few" is. If you shut down by the menu, then close the lid, it could be going into sleep mode before the shutdown is finished. So give it a "few more" seconds instead of just a "few."

 

[Randy B. Singer]

Thanks for the reply Randy. Yes I have been monitoring the battery condition with CoconutBattery. I have used the app. for many years now on various MBPs That's why this problem seems so unusual with a slow steady drain at an almost predictable percentage rate every day. I wouldn't think a battery would fail like that.

This is a used computer with an old battery. You have no idea how it was used...or abused. Is it really so hard to believe that an old battery, possibly subjected to abuse over many years, might not be able to hold a charge? It's easily possible that the previous owner left the laptop sitting with zero charge for months at a time. Or that they left it sitting at 100% charge, always tethered to the charger, for years at a time. (Either will cause lithium to plate onto the anode of the battery, causing a short circuit.)

You've likely never seen this type of behavior by a laptop battery before because you've never abused the laptops that you have owned. I'm willing to bet that one of the main reasons that the previous owner sold this laptop was because its battery was done, and he/she didn't want to have to purchase a new one.

 

[OneWonders]

Well you convinced me Randy. I will order a replacement. Thanks fort he discussion here.
Let you know soon how it went.
You guys are great

Could be, depending on how many seconds "few" is. If you shut down by the menu, then close the lid, it could be going into sleep mode before the shutdown is finished. So give it a "few more" seconds instead of just a "few."

Got it. I do wait for the screen and curser to turn off. Also it goes through the normal boot up procedure when I open the lid. So I assume that it was starting from a powered down condition.
Paul

 

[OneWonders]

double post sorry