New MacBook - Should i let my battery drain fully or charge it all the way.

[bmclaurin]

The rMB uses a hybrid 2-cell Lithium Polymer battery. Even with all the Apple wizardry, you can't avoid the basic chemistry of the cells. Lipo cells are amazingly tolerant of many usage conditions, but one general truth about all Lipo cells is that it is not good for their long-term health to remain deeply discharged for long periods of time. But they are perfectly happy to remain in a relatively full state of charge. In fact, most agree that a voltage of about 3.85v per cell (which equates very roughly to about 70-90% state of charge) is an ideal long-term "storage voltage" to maximize shelf life.

For all practical purposes, the only thing IMO that you need to avoid is allowing your laptop to remain deeply discharged for long periods of time (and even that is not going to somehow kill your battery instantly, but it would have gradual adverse impacts on its overall life span). Other than that, as others have said, use it plugged in when you can, and use it on battery power when you need to, without worry.

Just my $0.02.

 

[212rikanmofo]

Draining a battery completely is the best way to permanently kill your battery. A mac will shut down before it drains completely to prevent this from happening, but if you forget to charge it right away it will slowly drain to zero and kill the battery. I would never go much lower than 20%.

Best advice is to plug it in whenever practicable.

If thats the case, then why do people recommend on draining your battery completely and then recharging it to 100% at least once a month?

 

[tecnho]

If thats the case, then why do people recommend on draining your battery completely and then recharging it to 100% at least once a month?

They are saying that it exercises the battery, but apparently should only be done to around 20%

 

[cfedu]

If thats the case, then why do people recommend on draining your battery completely and then recharging it to 100% at least once a month?

Because no one has ever said that, lithium ion batteries should never be completely discharged ever. Apple products and almost all products will not let them be discharged completely, the device will shut down before it can be completely drained. You must recharge a Li ion battery once a device turns off due to low power, if you do not it will keep discharging until it reaches zero. Once it is completely discharged, a Li ion battery my never hold a charge again.

 

[bmclaurin]

Beyond that, Lipo cells become unstable and potentially volatile when they are over-discharged, which is why practically every consumer device that uses them have multiple safeguards built in to prevent them from discharging below a safe voltage. I don't know what low-voltage cutoff that the rMB uses, but I can assure you that a comfortable safety margin is built in.

In terms of discharging a Macbook, "0%" absolutely does *not* correlate to a cell voltage of zero or anything close to that. My guess is that the circuitry will not permit the cells to drop below something like 3.6v, which is a very safe margin, and this is the voltage to that would correspond to "0%" indicated capacity in the menu bar. As such, it will not harm to allow your laptop to discharge to "0%," but I wouldn't recommend making a habit of it. And if you do, you should recharge it soon thereafter. As I stated in my previous post, Lipo cells shouldn't remain in a deeply discharged state for extended periods of time, as it can eventually take its toll on the life expectancy of the cells.

 

[lchlch]

The rMB uses a hybrid 2-cell Lithium Polymer battery. Even with all the Apple wizardry, you can't avoid the basic chemistry of the cells. Lipo cells are amazingly tolerant of many usage conditions, but one general truth about all Lipo cells is that it is not good for their long-term health to remain deeply discharged for long periods of time. But they are perfectly happy to remain in a relatively full state of charge. In fact, most agree that a voltage of about 3.85v per cell (which equates very roughly to about 70-90% state of charge) is an ideal long-term "storage voltage" to maximize shelf life.

For all practical purposes, the only thing IMO that you need to avoid is allowing your laptop to remain deeply discharged for long periods of time (and even that is not going to somehow kill your battery instantly, but it would have gradual adverse impacts on its overall life span). Other than that, as others have said, use it plugged in when you can, and use it on battery power when you need to, without worry.

Just my $0.02.

So it's wrong to assume that at full capacity, heat has a larger impact on the lifespan of the battery? (Both from charging and by putting a load on the computer)

That's contrary to what I learned in regards to battery chemistry.

 

[tecnho]

which is why practically every consumer device that uses them have multiple safeguards built in to prevent them from discharging below a safe voltage.

Is this true for my 6400 Anker Li-ion portable charger? Should I refrain from discharging it beyond a certain level when charging my phone? Additionally, does it have similar safeguards in place?

 

[lchlch]

Most of the new devices actually DECREASE the charging voltage as the battery reaches close to being full. Many devices today will charge quickly to like 80% but take much longer to go from 80 to 100%. It is a battery saving feature.

This is why we still keep having battery threads. So much cr^p posted here.

Well that depends on the manufacturer. But for Apple it's mostly true. From what I've seen most of their product charge at 1c and the drop to 0.5c around the 80% mark.

However that does not change physics. More power is needed to charge a battery as it gets filled.

 

[212rikanmofo]

So is it safe to use our portable devices whether it be an iPhone, iPad or MacBook plugged in and battery at 100% most of the time if we're at home? Will this harm the battery at all or do these new batteries have some sort of intelligence to them that knows not to charge when the battery is at 100%?

85% of the time I'm using my macbook at home with it plugged in, and the only time I use it while unplugged is if I have to move around the house for awhile or if I'm going out somewhere.

 

[Newtons Apple]

So is it safe to use our portable devices whether it be an iPhone, iPad or MacBook plugged in and battery at 100% most of the time if we're at home? Will this harm the battery at all or do these new batteries have some sort of intelligence to them that knows not to charge when the battery is at 100%?

85% of the time I'm using my macbook at home with it plugged in, and the only time I use it while unplugged is if I have to move around the house for awhile or if I'm going out somewhere.

When fully charged the device stops charging the batteries. If left alone for weeks it will not harm the battery. You can not over charge your Apple device.

Best to use plugged in when power is available to avoid cycles.

 

[lchlch]

When fully charged the device stops charging the batteries. If left alone for weeks it will not harm the battery. You can not over charge your Apple device.

Best to use plugged in when power is available to avoid cycles.

Even if your Mac is always plugged in it will consume cycles.

 

[Newtons Apple]

Even if your Mac is always plugged in it will consume cycles.

Maybe so but MUCH SLOWER than if you used it all the time on battery.

 

[lchlch]

Maybe so but MUCH SLOWER than if you used it all the time on battery.

Actually it's the same speed.

When your battery hits 100% the charger stops charging and let's your Mac drop to about 95% than charge it back up.

 

[Newtons Apple]

Actually it's the same speed.

When your battery hits 100% the charger stops charging and let's your Mac drop to about 95% than charge it back up.

Same speed?

I am talking about cycle numbers. You number of cycles will not increase as fast, over time, with the device plugged in! It would take many 96% to 100% charges to equal a single cycle.

Thanks for your battery lesson

 

[lchlch]

Same speed?

I am talking about cycle numbers. You number of cycles will not increase as fast, over time, with the device plugged in! It would take many 96% to 100% charges to equal a single cycle.

Thanks for your battery lesson

I meant they would consume cycles at the same speed

1 big cycle and 25 4% cycles should provide the same runtime.

 

[DeltaMac]

Actually it's the same speed.

When your battery hits 100% the charger stops charging and let's your Mac drop to about 95% than charge it back up.

But, your example of one charging episode would NOT accumulate a charge cycle. All things being equal, you would accumulate one full charge cycle after about 20 of the charges as you describe them.
So leaving your Mac plugged in all the time (never using it on battery only) would accumulate charge cycles at a rate of (maybe) one or two cycles per month.

And, the runtime is not really a factor, as you are not using the battery's charge for running the Mac. The runtime is only relevant when you unplug from your power adapter.

 

[lchlch]

But, your example of one charging episode would NOT accumulate a charge cycle. All things being equal, you would accumulate one full charge cycle after about 20 of the charges as you describe them.
So leaving your Mac plugged in all the time (never using it on battery only) would accumulate charge cycles at a rate of (maybe) one or two cycles per month.

That's true if you don't use your laptop at all

Let's assume that surfing the web for 1 min consumes 1% of power (entirely made up), it would 100 mins to consume a big cycle and 100 mins to consume 20 5% cycles.

I hope that makes it clearer.

 

[Newtons Apple]

Threads like this is why there are more threads like this!

 

[tecnho]

Is this true for my 6400 Anker Li-ion portable charger? Should I refrain from discharging it beyond a certain level when charging my phone? Additionally, does it have similar safeguards in place?

Still no answer on this?

 

[lchlch]

Still no answer on this?

Most LiPo batteries will have that safeguard in place (would a manufacture make a battery that dies when a consumer discharge it to 0%?)

As for your other question I believe bmclaurin's post above explained it better that I could.

 

[Newtons Apple]

Still no answer on this?

L-Ions do not like to be discharged to near empty and left that way. It would help if you charged it up as soon as you can after discharging.

 

[usernames.taken]

Are people making up stuff to be funny, or do they actually believe all this stuff? I was going to try and respond to some of that stuff but I don't see the point.

The truth or falsity of these posts are irrelevant. Just use your computer however you want. Don't be afraid to plug it in or unplug it whenever you want. (That's how normal people who don't read MacRumors do it, and they get by just fine)

 

[tecnho]

New MacBook - Should i let my battery drain fully or charge it all the way.

Most LiPo batteries will have that safeguard in place (would a manufacture make a battery that dies when a consumer discharge it to 0%?)



As for your other question I believe bmclaurin's post above explained it better that I could.

L-Ions do not like to be discharged to near empty and left that way. It would help if you charged it up as soon as you can after discharging.

Thanks guys, I will try to charge it back to capacity after discharge if at all possible. It seemed that some people have recommended to avoid having the Mac battery drop to levels below 20% to optimize performance. If that is true, should similar practices be applied to a Li-ion charger as well?

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Don't be afraid to plug it in or unplug it whenever you want. (That's how normal people who don't read MacRumors do it, and they get by just fine)

But we DO read MacRumors

 

[usernames.taken]

Yes, you should also charge them at an angle to make them last longer. An approximately 30-40 degree angle is best. It helps the electrons flow better.

 

[GGJstudios]

Even if your Mac is always plugged in it will consume cycles.

Actually it's the same speed.

When your battery hits 100% the charger stops charging and let's your Mac drop to about 95% than charge it back up.

This is false. Apple's charging technology is designed to avoid such shallow discharges/recharges. Once fully charged, charging stops and your Mac runs on AC power. It will only use the battery while plugged in under extreme workload conditions.

Threads like this is why there are more threads like this!

Exactly! Too many people making it up as they go along.

Are people making up stuff to be funny, or do they actually believe all this stuff? I was going to try and respond to some of that stuff but I don't see the point.

I think some actually believe the nonsense they post. They read something in a blog or forum and don't bother to check to see if it's true before repeating it. Others who don't know any better tend to believe them, unless those who are aware of the facts corrects the misinformation being posted.

It seemed that some people have recommended to avoid having the Mac battery drop to levels below 20% to optimize performance.

Those people are wrong. There is no magic percentage for charge levels. Just try to avoid fully draining your battery. As already stated, run on battery whenever you need to and plug it in whenever you can. You can plug or unplug any time you need to, regardless of the charged percentage, and you never need to completely drain your battery.