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Anyone getting user experience of how this new BHM feature actually works? I upgraded from 10.14.6 to 10.15.5 on 6/3 and a few hours after successful upgrade I saw the battery charge level go down to the low 90s, then when I looked again it was back to 100%. That was 5 days ago and it has not happened again since. My unit had been plugged in about 99% of the time. I even tried toggling the checkbox and restarting - no effect.
 
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Saw the same go down the day I installed 10.5.5, then it never happened again and always charge and stay to 100%…
 
MacBookPro16,1 bought a month ago.
Ah, T2 chipset and new battery (T1 and 2½ year old battery for me). Please reply back here if that changes. It's good to know it is happening to a hardware range of users. Anyone else before I use my AppleCare and also submit a Feedback Assistant ticket?
 
UPDATE: 6 days after the 10.15.5 update and the initial charge drawdown from this feature, it finally did something again today. Slowly went down to 89% with the battery menu showing "Battery is Charged", then started charging and right back up to 100%. Any documentation or user experience yet? Cause this surely ain't gonna help my battery. If you keep an eye on the Activity Monitor/Energy/Battery (last 12 hours) graph at the bottom, you will be able to see these drawdowns.
(EDIT: I did restart about an hour prior to this happening)
 
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UPDATE: 6 days after the 10.15.5 update and the initial charge drawdown from this feature, it finally did something again today. Slowly went down to 89% with the battery menu showing "Battery is Charged", then started charging and right back up to 100%. Any documentation or user experience yet? Cause this surely ain't gonna help my battery. If you keep an eye on the Activity Monitor/Energy/Battery (last 12 hours) graph at the bottom, you will be able to see these drawdowns.
(EDIT: I did restart about an hour prior to this happening)
Is there a way to actively know that the battery draining from a plugged-in MacBook Pro is a result of the new Battery Health Management feature? I mean specific logs, or a hidden user interface element? Because I thought/think I have a faulty logic board and so many different Apple employees are treating it like a hardware issue when I'm realizing it might be the Battery Health Management feature. It's frustrating that the battery menu bar icon doesn't have a little mention of the feature being used to reassure the user that everything is intentional and operating as expected.
 
Is there a way to actively know that the battery draining from a plugged-in MacBook Pro is a result of the new Battery Health Management feature? I mean specific logs, or a hidden user interface element? Because I thought/think I have a faulty logic board and so many different Apple employees are treating it like a hardware issue when I'm realizing it might be the Battery Health Management feature. It's frustrating that the battery menu bar icon doesn't have a little mention of the feature being used to reassure the user that everything is intentional and operating as expected.
Why don't you simply switch off the BHM feature? System preferences, Energy Saver, Battery health.
BHM has been reported to basically do shallow cycles for permanently connected computers, where available. Basically, every so often it runs out battery little bit and recharges. This is suppose to help battery to extend its life on systems, which normally would be permanently on charger. You can switch it off and see, if it stops doing whatever you are observing. If not, it may be something else than BHM.
Typical Apple, BHM is suppose to be hidden and not visible to users. Too complicated for regular user. Considering, how many people are confused by it, I think they may be right ;-)
 
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Is there a way to actively know that the battery draining from a plugged-in MacBook Pro is a result of the new Battery Health Management feature? I mean specific logs, or a hidden user interface element? Because I thought/think I have a faulty logic board and so many different Apple employees are treating it like a hardware issue when I'm realizing it might be the Battery Health Management feature. It's frustrating that the battery menu bar icon doesn't have a little mention of the feature being used to reassure the user that everything is intentional and operating as expected.
jent, yes, just toggle off the feature. You should not see that behavior persist. Please let us know.

After observing the BHM feature on my 99% plugged into AC 15" 2017 MBP for a month, this is what I can report:
Approximately every three days the built in charge controller stops energy going to the battery. The finder battery menu shows one thing down to about 95% charge, then another as is shown by my attached screenshots. It gets down to about 90% then starts charging right back to 100%. That's it.

Here it is at 95%:
First Battery is charged.png

At 94%:
Second Battery is not charging.png

At 90%:
Third Battery charging.png

And the Activity Monitor showing the BHM induced cycle:
Activity monitor.png


As you can see, the Battery icon is showing fully charged and plugged in even when it is below 100% and even when it says "Battery is Not Charging".

Now whatever confidence you may have in Apple engineers to prolong the life of your battery, this behavior will not accomplish what the science shows. Here is an excerpt from just one knowledgeable source, Battery University (there are many others):

"A laptop battery could be prolonged by lowering the charge voltage when connected to the AC grid. To make this feature user-friendly, a device should feature a “Long Life” mode that keeps the battery at 4.05V/cell and offers a SoC of about 80 percent. One hour before traveling, the user requests the “Full Capacity” mode to bring the charge to 4.20V/cell."

Almost all batteries, including Lithium Ion and Polymer have a voltage associated with States of Charge (SoC). That is how the built in charge controllers know when to taper off the energy going to the battery and then provide just a small amount of energy (Watts) through amps (aka trickle charge) to keep it at 100% SoC. According to all the science I have seen, keeping these batteries at that 100% SoC all the time is not helping the longevity. But allowing the charge controller to keep the SoC at around 80% is good battery juju. And yes, you will only get 80% of your battery capacity, therefore toggle the feature off if needed to get back to fully charged.

I have spoke with three "Senior" Apple CS techs now and not one of them has a clue how the BHM feature was programmed. It's one thing to dumb down the features to a check box, but entirely different to provide no one with knowledge and have the white paper "About battery health management in Mac notebooks" no where near describe in detail the actual behavior, but does suggest that users like me should see it keeping a lower maximum charge. Doing that for less than one hour every three days is not going to accomplish the task.

The only people that may be confused by this are the people that actually have some technical knowledge and want to know if a new feature that is prolonging the inevitable cost of replacing a $200 glued in battery (that used to take less than one minute to replace) is actually working! With all the well documented glitches in the current macOS, it's quite prudent to allow people to be able to simply verify intended function.

If anyone else has anecdotes of their experience, please provide. I would like to know if there is hope for this feature, or should risk AlDente which does exactly what the science suggests should happen, even though having a third party write keys to the SMC firmware is something I definitely want to avoid. Maybe 10.15.6 which should drop in a few days will amend some glitches... 🤞
 
I have spoke with three "Senior" Apple CS techs now and not one of them has a clue how the BHM feature was programmed. It's one thing to dumb down the features to a check box, but entirely different to provide no one with knowledge and have the white paper "About battery health management in Mac notebooks" no where near describe in detail the actual behavior, but does suggest that users like me should see it keeping a lower maximum charge. Doing that for less than one hour every three days is not going to accomplish the task.
Thank you! Your comprehensive answer is just the confirmation I was looking for. I genuinely thought I had a logic board issue and several Apple employees didn't even think this feature could be the culprit.

I don't have a strong opinion on battery management and don't even mind re-enabling this feature, but I'm disappointed Apple didn't communicate this in more detail to their staff, to the public (as you say, the support document is pretty vague), and to the end user who has no idea that this is intended behavior as opposed to an accidental battery problem.

Cheers to your research and thanks for the data and screenshots!
 
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