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The MacBook line of computers from Apple currently includes the Air and the Pro version. These notebook computers offer users lightweight, portable devices with enough processing power to work for many business and entertainment needs. 

As with any portable computer, the MacBook needs its battery to run when it isn’t getting energy from a reliable power source. Therefore, using the computer during this time can impact the length of the charge. Eventually, you will need to find a power source to help top up the battery in your Mac.

It may not be typical for most users to allow their Mac batteries to discharge completely, but some Apple product owners wonder what might happen if they do so.

What Happens When a Mac Runs Out of Battery?

couple of things can happen if your Mac computer runs out of battery. First, the issue you face depends on the battery’s state when you manage to charge it.

Short Sleep

If the battery gets low enough, you may get some warning on your computer screen. However, the device should go into short sleep mode even if you do not receive a warning message

If this happens, the Mac will try to use the last of its remaining battery power to save the state in which it finds itself when the battery is running out of charge. “State” here could refer to the following:

  • Settings that are active in the computer
  • The programs that are running 
  • The data with which you are working during sleep mode activation.

If these three happen, we recommend plugging in the computer so it can draw energy from a power source as soon as possible. In doing so, you’ll be able to start charging the battery up right away. 

Pushing the power button on the MacBook should wake it. Once done, you should be able to restore the computer to the state in which you had it when it needed to enter this special rest mode. It is because the battery still had some juice left in it, and it could keep the system’s state in the memory.

Full Shutdown

When the battery on your MacBook gets low, you should get a warning that alerts you to this problem. If it gets lower still, the MacBook treats this as a danger level regarding the computer’s power reserve. The device might enter its short sleep mode to conserve energy. 

Because the MacBook has its internal monitor for the battery, the computer will write its current memory state to the disk, just like the example we outlined above. However, there is still a chance that the battery could completely discharge when it is in this state. 

It is particularly true if you cannot plug in the device to get more energy for the battery soon enough. If your MacBook goes through this event, you will lose the current state in which you have it. As a result, the computer will shut itself off completely, and you must do a complete restart once you charge it. Otherwise, you can wait for the battery to charge up again. In either case, a full restart means that your desktop should load normally

However, you will not have access to any programs in the state they were in when you were using them during the last session. You will need to start them again, and any data you did not manage to save will not be there when you return. It is also possible that you may get some warning messages about the Mac not being able to shut down correctly if this happens.

Why Does My MacBook Battery Say “Replace Soon”?

Unlike charging, your MacBook could also tell you that you need to replace the battery soon. There are a couple of reasons why this might happen, but any scenario involves more than just trying to keep the battery up to its total capacity. 

If your Mac is relatively new, any ‘replace soon’ message may mean that there is some fault in the part itself. You should not need to replace a new computer’s internal battery. It may be under its warranty from Apple, depending on when you purchased your device. A battery that is not holding a charge in a new Mac is something the company should be able to take care of for you as part of the warranty agreement.

If you get a message like this, the battery is failing. It could be that it is not holding a charge as it once did. Otherwise, it may be about to fall entirely. The Mac can monitor its battery, but it can be difficult to tell what to do just from the type of error message you get alone. 

In some cases, a Mac displaying this message could still last on its battery for months after the initial problem starts. However, letting a qualified technician look at your laptop in these situations is still an excellent idea. 

Further, there may be specific utility programs available for download that can try to tell you how many cycles the battery has discharged over its lifetime. Indeed, these same programs may offer an estimate of how many processes remain after the storm.

Will a Bad Battery Slow Down a MacBook?

Yes, a bad battery can affect the performance of your MacBook. However, it may not be as simple as this. There might be ways to determine if the battery is bad, but that doesn’t necessarily mean that this part of the computer is your only problem.

Unless there is a defect somewhere else in the system, most batteries do not start to go bad like this until the unit is at least several years old

As the parts inside a computer age, they are apt to function at levels that are not nearly as high or efficient as when the machine was new. It could mean that the fans don’t keep things as cool, the processor uses more energy to perform the same tasks as it did with ease, or the system is so full of digital junk that it seems clunky.

In any case, there are still ways that a faulty battery can make things harder for your MacBook. One of the main things that might happen here is the production of extra heat.

Heat does not mix well with sensitive electronic components; the battery is one part of the system that generates this heat. So a bad battery may put out far more heat than one that is normal, and it will send this extra warmth throughout your system. 

The cooling measures inside a laptop will try to take care of this, but they may already tax themselves by keeping things like the processor and graphics card cool.

An old or bad battery can run hotter than it should, but it might also heat up even more when you plug in the computer to charge it. It is particularly true if you want to charge an old battery while using the laptop

In addition, if the battery or charging circuits are bad, it could make your computer run slowly, stutter, lose data, or even restart inconvenient times.

Can a MacBook Turn On Without Its Battery?

Yes, a Mac should be able to run without its battery. It will do so with a reduction in performance to prolong the machine’s life. 

Under normal circumstances, the Mac can handle spikes in energy usage by pulling that extra energy from the battery. Without it, the unit will throttle its performance to ensure that these spikes do not happen.

Is It Okay To Use My MacBook Without a Battery?

Although the choice is up to each user, it should be okay to run the MacBook without its battery. At most, you should only do this for short periods of light work, especially since the machine may only use half of its resources to give you some marginal performance levels.


The battery is an essential component in any MacBook, but these light laptops can still run without one using other sources of energy. However, the system will cap the performance of your Mac at a particular level during these times. Bad batteries can also slow down your whole computer significantly, so it is wise to pay attention to any battery error messages that you receive.