Catalina Battery Health

[myrtle14]

What have you noticed when using this feature. My MBA 2020 is plugged into the wall charger 24/7.

Battery Health is activated.

I see the menu bar charge level step-wise decrease over time to 92% charge level then slowly return to
100%. Battery cycle count increases slowly - over a few months it is at 17 cycles.

Thoughts?

 

[asv56kx3088]

That's what the Battery Health Management supposed to do.

 

[lambertjohn]

Battery cycle count shouldn't increase if the battery level is only dropping to 92% and then going back up. Somebody correct me if I'm wrong.

 

[CheesePuff]

Battery cycle count shouldn't increase if the battery level is only dropping to 92% and then going back up. Somebody correct me if I'm wrong.

well it would count as 1 cycle if it did that 12 times

 

[lambertjohn]

well it would count as 1 cycle if it did that 12 times

Say what??

 

[BigMcGuire]

Say what??

cheesepuff is right. A full cycle is 0-100%. So ten times of 90-100% would count off a cycle.

 

[lambertjohn]

cheesepuff is right. A full cycle is 0-100%. So ten times of 90-100% would count off a cycle.

That's ridiculous and so not true. For most modern MacBooks, Apple estimates the battery can last through 1,000 cycles. A cycle count means using ALL of your battery's power and then fully recharging it, whether you drained your battery in one sitting or off and on over the course of a few days or weeks. NOT 10% x 10.

 

[BigMcGuire]

That's ridiculous and so not true. For most modern MacBooks, Apple estimates the battery can last through 1,000 cycles. A cycle count means using ALL of your battery's power and then fully recharging it, whether you drained your battery in one sitting or off and on over the course of a few days or weeks. NOT 10% x 10.

I think we're saying the same thing.

Image taken from: https://www.apple.com/batteries/why-lithium-ion/

If I drain my battery 10% ten times, then charge it to 100% I'll consume 1 charge cycle. If I drain my battery 50% twice then charge it to 100% I'll consume 1 charge cycle. If I drain my battery from 100% to 0% and charge it to 100% I'll consume 1 charge cycle.

And yes, most recent Apple notebooks will have 1000 charge cycles and retain 80% of their design charging capacity with a one year warranty (or 3 total with AppleCare+).

Batteries - Service and Recycling

Learn about battery service and recycling for Apple devices. All rechargeable batteries need to be serviced eventually.

www.apple.com

 

[Weaselboy]

Determine battery cycle count for Mac laptops - Apple Support

Learn how to determine the number of cycles your Mac laptop's battery has.

support.apple.com

@BigMcGuire is spot on. Here is an Apple support doc on the subject.

 

[Loog]

I've noticed a huge reduction in my battery health since updating and enabling this function. First was a loss of 3% within 3 charge cycles and now some 2 months later I've lost 7%.

I started off with 100% which has progressively eroded, while my usage hasn't changed that much. I'm on power while working in the day and off for the rest of the day, sleep at night. I'm a little concerned that this is going to deteriorate at this rate which will leave me with a device that will need to be constantly connected to power.

I'm impressed that at 1.5 years I'd still got full capacity this would fluctuate between 97% and 100% if I let this run to within 5% when I noticed the percentage was dropping. Now this is like a cliff edge!

I've reset the SMC which has had no effect, I'm going to closely monitor this as I'm a little suspicious that the battery health feature may be not having the desired effects in real life as on paper.

I've seen the same on my SE 2020, 2 months old and 2% lost, XR which is 14 months is still at 100%.

Is there some synthetic battery ageing going on?