MacBook Pro 16" M1 Max, battery health, cycle count, and replacement questions

AbdulWahid0214 wrote:

1. I'm evaluating a 16" M1 Max (2021) with 85% maximum capacity and 900 cycle count, condition showing Normal. Before relying on it as a daily machine for the next few years, I'd like to understand a few things:

Apple rates these for 1,000 cycles at 80% capacity. At 900 cycles still showing 85%, what should I realistically expect for capacity over the next 12-24 months of regular use?

Apple expects a battery to have a lifespan of ~1000 cycles. Apple considers battery health of 80% to be the accepted minimum regardless of cycles.

Realistic estimates are difficult to make because batteries don't all age the same. Yours at 85% today may show on 80% in a few months. Another might not make that drop for a year. How you use the computer, environmental conditions and battery chemistry all affect battery health.

2. Does battery health affect performance on a MacBook when plugged in, or is it purely a runtime/portability matter? I've read conflicting things about power-delivery throttling on weaker batteries.

Unless a battery is severely depleted, no, the battery health doesn't much affect the MacBook performance when it is plugged in. The MacBook is "battery capable", but not really designed to run on battery al the time as an iPhone or iPad is. The best, full performance is got when the computer is plugged in. The computer can draw what it need directly from the wall adapter. When running on battery only, then yes, performance may be throttled when the battery becomes depleted.

3. When Apple performs an out-of-warranty battery replacement on this model, does the service include the keyboard and trackpad (top case), or is it battery-only?

It's my understanding that, with Apple's current crop of laptops, the battery replacement does include top case, keyboard and trackpad.

You can contact Apple directly to ask about that.

Get your Mac repaired and see how much will it cost: Mac Repair & Service - Apple Support 

4. Is there a capacity or cycle threshold at which battery swelling becomes a real risk, and what are the early warning signs?

Battery swelling is a serious concern and may happen at any time regardless of health or cycle count. Some indications are a trackpad that doesn't click, some keys may become intermittent or inoperative, seams along the edge may appear to be more pronounced or you may see bulging of the case itself.

If you suspect a battery is bulging, stop using the computer immediately. Do not plug it in to charge and have it serviced as soon as possible by Apple or an Apple Authorized Service Provide.

You can make a Genius Bar appointment for hardware/software service and support using this link: Make a Genius Bar reservation - Apple Support

Customer Support (800) MY–APPLE (800–692–7753) or on line /getsupport.apple.com/ 

or call AppleCare Support at 1-800-APLCARE (800-275-2273) 

Outside the US: Apple’s global phone numbers: Contact Apple Support 

Trying to make an informed decision. Thanks.

Very wise.

AbdulWahid0214 wrote:

1.Apple rates these for 1,000 cycles at 80% capacity. At 900 cycles still showing 85%, what should I realistically expect for capacity over the next 12-24 months of regular use?

No idea because we have no idea of the battery's actual health & behavior. The battery may end up showing issues under load, especially when the battery charge level gets low (usually less than 20%, but not always). The numbers you are throwing around are just the cases where Apple will replace a battery.

The 80% number is no longer accurate for Apple to consider a battery replacement. I've had the Apple Diagnostics report the battery as "Ok" even when the battery's Full Charge Capacity was less than 75% of its original Design Capacity. Up until a few years ago...80% "health"/"Max Capacity" was when the Battery Condition in macOS would toggle to "Service Recommended" & cause an alert with the diagnostics, but not anymore. I have no real clue what value Apple uses to trigger a "Service Recommended" condition for replacement.

2. Does battery health affect performance on a MacBook when plugged in, or is it purely a runtime/portability matter? I've read conflicting things about power-delivery throttling on weaker batteries.

Generally no, but some battery failures can cause power related issues which could affect performance, or if the system is no longer able to communicate with the Battery's temperature sensor.

3. When Apple performs an out-of-warranty battery replacement on this model, does the service include the keyboard and trackpad (top case), or is it battery-only?

It depends on the laptop. Some Apple Silicon laptops can have just the battery replaced while others will still require having the entire Top Case/Keyboard/Battery Assembly replaced.

4. Is there a capacity or cycle threshold at which battery swelling becomes a real risk, and what are the early warning signs?

No. Any Lithium Battery can swell at any time. Environmental & use factors play a part as does the manufacturing process.

Unfortunately if you are trying to evaluate the health of a battery in a used laptop you are considering purchasing, then I would say the Battery is likely close to wearing out or even failing if it is not already there. Just assume the Battery will need to be replaced if you are going to use it on battery only for anything more than 1-2 hours.

Unfortunately there is no easy way to determine the battery's true condition from the information Apple provides to the user....even the Apple Diagnostics won't catch most battery failures these days. I had to write a script so I could test & monitor the batteries in macOS to better determine an Apple battery's true condition/health so I could better support my organization's Macs. With the Intel Macs I could have given you a command to run, but Apple broke that utility when they released the Apple Silicon Macs by having it pull incorrect data from the battery.

As @etresoft mentions....you must be extremely careful purchasing a used Mac these days since the previous owner may be able to retain control of the device unless it has been properly prepared for sale. If it is a corporate/educational laptop there is an even higher chance that the device could remain part of their MDM management system where they could flip a switch & remotely lock the device. I'm not sure there is any way to be sure a device has been removed from an MDM. Apple can detect it, but Apple doesn't provide this information to end users. Unless you are purchasing from a trusted source, you are at risk. The safest option for a properly refurbished Mac should be from Apple's own site...just make sure to keep the receipts.

AbdulWahid0214 wrote:

I'm evaluating a 16" M1 Max (2021) with 85% maximum capacity and 900 cycle count, condition showing Normal. Before relying on it as a daily machine for the next few years, I'd like to understand a few things:

...

Trying to make an informed decision. Thanks.

Never, ever buy a used Mac.

Just for comparison, I have a very similar computer, with an M1 Pro instead of an M1 Max, purchased new. I've used 110 cycles. 900 cycles is worn out.