Macbook Pro A1990 - Battery design capacity going down so fast from 80%
MacBook Pro 13″, macOS 12.5
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Thanks everyone for your comments, but the problem was with the battery capicity sensor. During the use of the MacBook, I discharged and charged it very often and not always correctly (from 30% to 60%, or from 50% to 80%). And it seems that the sensor simply forgot what the real capacity of the battery is. So I discharged the MacBook to 0% and left it overnight, then charged it to 100% (without interruption) and desgin capicity went back to 82%.
Technically the Design Capacity is not the value being shown on the bar and has not changed since manufacture. The bar is representing the relation of the battery's current Full Charge Capacity (FCC) in relation to the original Design Capacity of the battery. You can prove this by doing the math by dividing the Full Charge Capacity by the Design Capacity:
5320 / 7336 = .72519
.72519 * 100 = 72.519 %
But yes, this battery's FCC is below 80% of the original Design Capacity so it should be replaced if the battery is not performing to your needs. macOS should be showing a "Service Recommended" battery condition and the Apple Diagnostics should be reporting a worn out or failing battery. Have Apple or an Apple Authorized Service Provider examine the laptop to provide you with a repair estimate.
Keep in mind Apple will not even look at the information in Coconut Battery. Many techs won't even understand what is being displayed. Apple and AASPs only care about the battery condition reported by macOS and more importantly the results of the Apple service diagnostics. I just saw a post earlier today where a user mentioned their battery condition was "Service Recommended", but Apple would not replace the battery because their service diagnostic did not report a battery issue (no idea if the battery was still indicating a "Service Recommended" condition at the time Apple was examining the laptop....the condition can be intermittent at times especially if the battery is at a borderline condition).
Batteries are a wear item, like the soles of your shoes or the tires or brakes on a car. After some use OR the mere passage of time, your should expect to have to replace them.
You have posted a battery report above, telling you, "It's Time".
if you want to have battery operation, you will need to replace that old tired battery.
This is not necessarily based on anything you did (or did not do). Results for any specific battery are wildly variable.
ooleglysiak wrote:
So I discharged the MacBook to 0% and left it overnight, then charged it to 100% (without interruption) and desgin capicity went back to 82%.
Don't ever leave a Lithium battery completely drained overnight as it can permanently damage a Lithium-ion Battery. It is fine to let the battery go to 0% then connect a charger right away, but avoid leaving it at 0% for an extended time.
FYI, The "Service Recommended" condition can be triggered in two different ways. One is when the Full Charge Capacity drops below 80% of the original Design Capacity. Two, if macOS detects a hardware fault with the battery. Both of these can intermittently show "Service Recommended", then later on show "Normal" condition. The only time you really have to worry about replacing the battery is when the battery is not performing up to your expectations....and as long as the condition shows "Service Recommended", then Apple will most likely allow for a battery replacement since it should fail the Apple service diagnostics especially if "Service Recommended" condition is always displayed.
Thank you for your comment. This was as an example of how to fix the problem, however I never discharge my battery below 20% as it is really dangerous.
Macbook Pro A1990 - Battery design capacity going down so fast from 80%