Repareer je spullen Gemeenschap Winkel

Released June 2012 / Core i7 processor with Turbo Boost / Up to 1 GB GDDR5 Video RAM

596 Vragen Bekijk alle

Opties

Battery shows 0 mAh capacity after replacing a cell

Hi guys,

I have a MacBook Pro 2012 (non retina) with a swollen battery. The battery still worked fine, holding some charge for about an hour, but I decided to fix it.

I opened the battery, discarded the swollen cells, and replaced them with healthy cells from a donor battery from another MacBook Pro 2012. I checked all six cells with a LiPo charger, and they all hold >90% of the original capacity, so they are very good. I charged all cells individually, double checked all connections, and soldered everything together. A multimeter shows 11.1 V at the battery terminals, so far so good…

Unfortunately the MacBook Pro does not power up with this refurbished battery. It boots with the power adapter connected though. Both MacOS and CoconutBattery recongise the battery serial number, manufacturer, age, and so on, but show 0 mAh and the Mac does not charge or use the battery. As soon as I remove the power cord, the MacBook Pro shuts down.

I have reset SMC and made no difference.

Any clue of how to fix this?

UPDATE 02/10/2021

CoconutBattery snapshot

Block Image

Beantwoord deze vraag Dit probleem heb ik ook

Is dit een goede vraag?

Ja Nee
Score 1
2 opmerkingen

Let’s get a better view of things, install this gem of an app! CoconutBattery take a snapshot of the apps main window and post it here for us to see Voeg afbeeldingen toe aan een bestaande vraag

door

@danj Question updated with a CoconutBattery snapshot.

door

Voeg een opmerking toe

3 Antwoorden

Filteren op:
Meest nuttige Nieuwste Oudste
Het nuttigste antwoord

Opties

I’ve never rebuilt a pack before, but I’ve tempted fate before so I have a bit of experience and know how downright dangerous charging 0V packs can be, and rebuilding.

A lot of laptop batteries today have a one-way permanent failure flag, with some being more aggressive than others - even if you can safely rebuild it. In some cases, especially systems like the Lat E series and 3/5/7/9000 series, a custom TI chip combined with a sensitive BIOS (AFAIK the removable Lats are picky with the E Series, but not sure about the built-in series) also get in the way. That was not a problem on Lat D machines.

Why the change? Shoot for Sony producing faulty cells, which led to a multiyear battery recall which went on from 2005-2008. Before those years, we used to be able to abuse batteries without a permanent failure flag that’s easily triggered; it was there, but you had to be incredibly bold to trip it. You could even swap cells without killing the BMS. On a lot of the older batteries, I’m still able to charge an unused pack from 0V even if it’s been sitting for years (Yes, this is a somewhat dangerous game to play. I DO MONITOR THESE!) and has been the case for over 10 years. The way I see it is if the pack is probably bad, why not try? The manufacturers removed that endurance with cheaper cells and trigger happy BMS boards which trip a permanent failure way more easily then they used to. In addition, a lot of post Sony packs block charging below 3.5-3.7V. You can still tell the thing you mean it, but you need to trick the computer OR use an external charger that tells it where to shove the complaint. The closest we have to that time is Samsung SDI, which can take a similar beating as the Sony cells (but cannot charge a 0V pack, thanks to the modern BMS issues). If it can be done, I’ve found a way.

Sadly, you may need to give in and buy a new pack. The days of taking an old pack from something like a pre-2005 HP and early PB G4 packs where there were no nannies are over, and so are packs that last 10+ years and still work even if they sit thanks to Sony.

Was dit antwoord nuttig?

Ja Nee
Score 2
Voeg een opmerking toe

Opties

I’m suspecting you will need to reprogram the batteries microcontroller or at least see what it is telling you.

Frankly, its just best to replace the full assembly as the sensor logic within the battery could have been damaged which is causing the microcontroller not to work properly.

Was dit antwoord nuttig?

Ja Nee
Score 1

6 opmerkingen:

A visual inspection at the microcontroller board does not show any damage. But I have two cheap 3rd party batteries in working order that I can scrap and take their boards. Do you think it could work or will those boards get stuck on 0 mAh capacity too as soon as I desolder them from their cells?

door

I find it best not to play around with the battery cells and the micro-controller board.

The risks are more than damaging something, you could cause a fire or hurt your self.

Unless you have a deep understanding on how this all works its best not to temp fate.

door

I play around with LiPo's in my job so I know what I am doing in that matter. What I don't know is what the board or the Mac is doing to set the battery as faulty and with zero capacity.

One of my guesses is that the board sets itself to a faulty battery status when it looses supply. Since it is installed within the battery, it has seen power since manufacturing until the day I detached it from its cells... And I wonder if there is any way to reset that faulty status flag. But hey, this is just one of multiple guesses and you the pros will probably know what is going on better than I do.

door

@alreiber - Sorry I haven't done a deep dive into the microcontroller logic Apple uses in this battery. Here's some useful references if you're up to it ;-}

Teardown: Debugging a faulty MacBook Pro battery

Some other stuff I have

Apple's 2009 MacBook Pro: Battery Life to Die For

How a security researcher discovered the Apple battery “hack”

door

@danj it probably has a one time permanent failure flag. I went into it a bit on why we got to this point.

door

1 commentaar meer tonen

Voeg een opmerking toe

Opties

The battery management IC inside the battery pack will produce a permanent failure when it sees a severe cell imbalance. You created that imbalance when you reworked the stack. This is 100% correct behavior by the management IC, since a severe imbalance can lead to fire/explosion. Also, replacing some of your cells with cells from another pack guarantees a cell imbalance, since it is pretty certain the new cells don’t have the same use history and aging. Cells are matched at production time so that they are all the same. You should never replace individual cells in a lithium battery stack.

Make no further attempt to use this battery. Buy a new one.

Was dit antwoord nuttig?

Ja Nee
Score 1

3 opmerkingen:

You know how easy manipulating a "0%" battery used to be? Shut the notebook down and DO NOT turn it on until it's done the job, run it and it doesn't care or do it externally as a lot of packs could be done direct for years.

Yes, the notebook approach is still dangerous-ish, but it's supervised. Going straight to the pack is like jumping a car; you get it in a computer once you got it into the marginal range. Like I said, Sony ruined the party. I hate these modern packs so much with how easily they get permanently blocked today.

Also, it's BS that cell imbalance does it -- I've had Dell batteries from both my E6540 (iDP FHD), E6440 (LVDS HD+) and to an extent my E7440 with obvious balance issues (you can tell by the BMS permanently lying about the runtime, no matter how many times you do 0>100% recals) do not get blocked. I've run them into the ground even when ePSA threw a fit and they put up a fight, as long as they're Samsung SDI packs. I've gotten 400+ cycles out of "unbalanced" packs clearly rated for 200-250 cycles and ran the SAME PACKS for 5 years. I do not remember the final count before it died, but I once ran one of my favorite Dell packs (NX31D) into the 425+ range before it croaked. On the other hand, I have a Dell NX31D that didn't make it there due to the machine being straight up purchased used and the battery wasn't taken care of.

door

I said *severe* imbalance. What I was referring to was 0 volts on a cell (a disconnected one). Make no mistake, that will kill the pack. This is entirely correct (required) behavior since a severely depleted cell (below about 1.9 volts, depending on chemistry) will deposit copper on the cathode and will be dangerous to charge. You will probably get the infamous fire/explosion, and you don't want that.

Lesser imbalances are handled by the cell-balancing circuitry under the control of the battery management MCU. It can do only so much, of course, so the battery capacity will be reduced to that of the weak cell, as you have observed.

door

@ffixitwell - Correct Fred! Not worth the risks and just smarter to get a replacement battery unit, let someone else deal with the mess if the battery is still under warranty.

door

Voeg een opmerking toe

Voeg je antwoord toe

Alreiber zal eeuwig dankbaar zijn.
Weergavestatistieken:

Afgelopen 24 uren: 0

Afgelopen 7 dagen: 2

Afgelopen 30 dagen: 17

Altijd: 1,118