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2010 Macbook Air Throttling when battery half empty

For some reason, my Macbook Air is throttling and not running at full performance when the battery level is under 40 ish percent. I have iStats Menu and it seems like the CPU is peaking around 140 degrees compared to the 180-190 that I normally get when I use my computer at full load at battery percentages above 40. And the fans never spin up as well. And when the battery gets under 20 percent, the temperatures max out at 120 and the fans never spin up either. And the computer runs much slower and the lag gets worse. However, the moment I plug in my computer, the lag stops immediately and then the temperatures go back up to 180-190 like usual and the fans spin up.

I thought it was a battery issue because sometimes I would get a “service battery” message that occasionally goes away. I replaced the battery but I am still experiencing the same issue. Is this normal behavior or do I need to get another battery replacement? I know that macs tend to throttle when the battery is removed.

Topic

I’m sure there’s more on the web about this.

In reply to 2010 Macbook Air Throttling when battery half empty

Given what we know about how to avoid a seemingly random shutdown, it would be a good design to throttle on old batteries at less than half full.

-> In other words I think this is a correct thing to do.

Not sure about that

In reply to I’m sure there’s more on the web about this.

I put in a brand new battery and it still does the same thing.

Not so much what you think you have bought

In reply to Not sure about that

But when was the battery actually made?

It can be new never used and still a few years old, have a look on the battery Specification Label and see when it was made that should be there.

Just checked

In reply to Not so much what you think you have bought

The date of manufacture shows 2019 but the battery health was at 100 prevent even after calibrating.

And even then.

In reply to Just checked

From memory laptops of many makes throttle to avoid an unexpected shutdown on battery power.

Need full throttle? Plug it in.

Well from my reckoning the battery is 2 years old.

In reply to Just checked

Despite what the Software tells you it may very well be ok within the Specifications of a battery that old but it is unlikely to be the same as a battery made yesterday though putting it through several charge discharge cycles may improve it some and ideally the proper discharge cycle than a slow charge would be better but I’m not aware of any devices that can do this with a NB Battery, The Batteries I use in my RC Aircraft have a balance charger that controls them and looks after them so the batteries last a long time or burst into flames, I’ve had both happen with Flight Packs over 10 years old and still in great condition but at the same time I’ve had a new battery burst into flame on the first charge so it’s very much Pot Luck with any battery.

But as stated elsewhere NB’s had issues with them shutting off when the batterie was down so Throteling the things back when they have limited power isn’t a bad thing as it saves loosing a lot of data if they shut down uncontrolled and is something I’ve seen quite a lot in other brand NB’s which after all where never really designed to be run on battery that is why they have power packs that come with them and provide controlled power rails that are both stable and within the makers limits. A Battery still produces different voltages in all the NB’s I’ve ever worked on but they need not provide the correct voltages or Amperage on all outputs or even if they are the stability may not be there which is very common with batteries as they change dramatically quickly.

Unless you want to put a Crow onto every rail and measure the voltages and so on over time I think you’ll find this is how the unit should work when the battery reaches a set level on any rail.

Not everyone recalls prior discussions

In reply to Not sure about that

About laptops that would seemingly power off with less than half a charge. In the end it’s all about avoiding that scenario so a good laptop will throttle to avoid shutdown and extend time on battery.

I see Jimmy noted the battery age issue but from my view of decades in this industry I see nothing wrong with this laptop’s behavior.

A couple of things

In reply to 2010 Macbook Air Throttling when battery half empty

To start off how good in the new battery. It may be new but has been in storage for a while and it’s not as good as it could be.

Everything you are describing is to do with a battery with not the capacity it should have and the fact that it works properly when plugged in tends to support the idea that the battery doesn’t have the capacity it once had or should have.

The other thing to look at is being a NB they tend to not be sat on things properly and suck dust and other crud into the cooling vents inside them which block up and cuts down the airflow over the hot bits and they do not cool properly. I’ve seen them so blocked up that no air comes out the exhaust vent at all though the fan spins madly.

This happens because they suck in small bits of fluff, dust and whatever else is in the air and this catches on the heatsink/s and blocks them. In extreme cases it looks as if the heatsink is coated in thick felt and no air passes through it.

I don’t let any NB go out of here without a Cool Pad as this fixes the worst of the problems of NB’s sat on fabrics like Table Cloths, Legs and so on so they can not suck in the crud to start off with. Sure it makes them run a shorter time on Battery but keeps them alive much longer. After all not much use if the NB is rebooting every 30 seconds because it’s overheated is it?

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