Battery Maintenance: Part 53 ;-)

As you know, Tesla is using the same cells that are used in notebook-batteries (or am I wrong here?).

Wrong. Lithium yes. Otherwise no.

Tesla states that the ideal range to use is between 20-80% of the capacity of the battery.

Yes, Exactly correct. That however doesnt mean "dont fully charge your battery" (see below)

Now the guy on youtube claims that it is actually very important not to charge your battery to 100% and not immediately use it.

100% nonsense

He says it's extremely harmful to empty a battery and let it sit in that state (that's quite well known),

100% correct

but he says it also harmful to charge it fully and let it sit.

Nonsense. Sitting on charge at 100% not good always/often, charging to 100% and "letting it sit" , no problem

"Apple does not recommend leaving your portable plugged in all the time."

Use the battery all the time, or use AC all the time, and use the batter once a week or once a month, as Apple recommends?

Here:

General consideration of your MacBook battery

Contrary to popular myths about notebook batteries, there is protection circuitry in your Macbook and therefore you cannot ‘overcharge’ your notebook when plugged in and already fully charged.

However if you do not plan on using your notebook for several hours, turn it off (plugged in or otherwise), since you do not want your Macbook ‘both always plugged in and in sleep mode’.

Do not perform “battery calibration” on your current Macbook. There is no calibration of current Apple portable Macbooks with built-in batteries.

A lot of battery experts call the use of Lithium-Ion cells the "80% Rule", meaning use 80% of the full charge or so, then recharge them for longer overall life. The main quantified damage done in the use of Lithium Ion batteries are instances where the internal notebook battery is “often drained very low”, this is bad general use of your notebook battery.

All batteries in any device are a consumable meant to be replaced eventually after much time, even under perfect use conditions.

➕If the massive amount of data that exists on lithium batteries were to be condensed into a simplex, helpful, and memorable bit of information it would be:

1. While realistically a bit impractical during normal everyday use, a lithium battery's longevity and its chemistry's health is most happy swinging back and forth between 20% and 85% charge roughly.

2. Do not purposefully drain your battery very low (10% and less), and do not keep them charged often or always high (100%).

3. Lithium batteries do not like the following:

A: Deep discharges, as meaning roughly 10% or less. Avoid this in all instances if you can. This is hard on your battery.

B: Rapid discharges as referring to energy intensive gaming on battery on a frequent basis (in which case while gaming, if possible, do same on power rather than battery).

C: Constant inflation, as meaning always or most often on charge, and certainly not both in sleep mode and on charge always or often.

From Apple on batteries:

http://www.apple.com/batteries/notebooks.html

http://support.apple.com/kb/HT1446

"Apple does not recommend leaving your portable plugged in all the time."

My question is: If this applies also to my notebook battery, would it be better to NEVER charge my battery fully, thus always using it on battery power (unless when I'm charging it). In my case, I use it at home, so the alternative would be to use it 90% of the time on AC power, but the battery isn't removable, so it would be fully charged all the time. So what is better? Use the battery all the time, or use AC all the time, and use the batter once a week or once a month, as Apple recommends?

Its not full charging that is damaging, but 1. parasitic charging, and 2. ALWAYS fully charged.

Your "either or" premise is wrong on both counts, see above.

In a lithium battery, deep discharges alter the chemistry of the anode ➕ to take up lithium ions and slowly damages the batteries capacity for the cathode ➖ to transport lithium ions to the anode when charging, thereby reducing max charge levels in mAh. In short, radical swings of power to lithium cells disrupts the chemical ecosystem of the battery to hold charges correctly which likewise impedes the perfect transfer of lithium ions both in charging and discharging. In charging your lithium battery, lithium ions are “pushed uphill” (hard) to the anode, and discharged “downhill” (easy) to the cathode when on battery power. Deep discharges, damages this “upward” electrolyte chemistry for the battery to maintain a healthy charge and discharge balance relative to its age and cycles.

From BASF: How Lithium Batteries work

https://www.youtube.com/watch?v=2PjyJhe7Q1g

.*You don’t want your Macbook both always plugged in AND in sleep mode (When portable devices are charging and in the on or sleep position, the current that is drawn through the device is called the parasitic load and will alter the dynamics of charge cycle. Battery manufacturers advise against parasitic loading because it induces mini-cycles.)

Keeping batteries connected to a charger ensures that periodic "top-ups" do very minor but continuous damage to individual cells, hence Apples recommendation above: “Apple does not recommend leaving your portable plugged in all the time”, …this is because “Li-ion degrades fastest at high state-of-charge”.

This is also the same reason new Apple notebooks are packaged with 50% charges and not 100%.

kurt hahn1 wrote:

... use the batter once a week or once a month, as Apple recommends?

This.

There is little point to any other practice, since charging current and discharge cutoff points are parameters that are inaccessible to the user, or even to the operating system. You may hear admonitions to "never" charge to 100% and "never" let a MBP shut off on its own due to low power. They are pointless, since those display units are a function of algorithms not under the user's control. In terms of the number of coulombs of charge present, the display units of 100% or 0% mean practically nothing. Without having seen it, the youTube video is likely to be as reliable a source of information as most YouTube videos, including those claiming you can recharge an iPhone by microwaving it.

Electing to constrain your usage to a range of 20 to 80 percent completely wastes 40 percent of the battery's available capacity. If you want to do that, fine, you won't hurt anything, but you're significantly limiting your Mac's usefulness by doing so.

Follow Apple's recommendations, specifically: don't leave a battery fully discharged for a prolonged period of time, don't leave it plugged in all the time, and when you store it for a prolonged period of time (weeks) do so at about 50% charge. Don't leave it in a hot car or out in the sun. Finally, realize that all batteries will eventually fail and require replacement. Allocate about 50¢ a week for battery depreciation and you will have more than enough when you need to replace it.

A Tesla will require considerably more than 50¢ a week, but its batteries will eventually need to be replaced too, regardless of what YouTube experts might prefer to believe.

John Galt wrote:

1. You mean hear... "never" let a MBP shut off on its own due to low power. They are pointless, since those display units are a function of algorithms not under the user's control.

2. Electing to constrain your usage to a range of 20 to 80 percent completely wastes 40 percent of the battery's available capacity.

1. 100% incorrect. Deep discharges are unquestionably a fast path to battery destruction as countless 1000s of posts on this board are proof.

With Apple’s adaptive charging system mitigates much potential for accidental battery misuse or abuse; however it is still readily possible to abuse the battery and thereby affect battery health.

..... as such point #1 is incorrect. The macbook will deliver ALL power it can until shutdown.

While this is, of course, not 0%, it is never the less deep draining the battery and very hard on it.

Using a Macbook up to the point involuntary shutdown by the SMC is defacto "deep draining" of the battery, and hard on same.

2. 100% incorrect. Nothing is wasted, however using 1/100th of 1 cent of "remaining electrical charge" on the battery down to a DEEP DISCHARGE often translates into = Early and premature death of an 'expensive' replacement battery.

Squeezing 1 cent of charge out of a battery which translates into premature battery (expensive) death is counter-productive. However whatever charge is left on the battery before recharge, is NOT lost in charging it.

battery experts call the use of Lithium-Ion cells the "80% Rule", meaning use 80% of the full charge or so, then recharge them for longer overall life. The main quantified damage done in the use of Lithium Ion batteries are instances where the internal notebook battery is “often drained very low”, this is bad general use of your notebook battery.

There is no "wasting" a battery that is recharged at say, 20%, since the 20% anode ionization (charge) is not lost in the recharge.

As I wrote it is not possible for a user to deep discharge a MBP's battery. It is certainly possible for it to become irreversibly damaged, by leaving it in a discharged state for a prolonged period of time, or by exceeding its environmental specifications.

Though they certainly can be entertaining, just like Rambo, I don't expect to become enlightened by YouTube videos produced by clueless "experts".

BTW, how did you calculate those 50c/week?

The cost for an Apple replacement battery given average usage.

I do agree that there's a lot of sh** out there,

Much of it can be found in this Discussion.

John Galt wrote:

it is not possible for a user to deep discharge a MBP's battery.

There are none who would agree with that assumption, including Apple.

SMC involuntary shutdown occurs before high level harmful discharge occurs (which shouldnt be repeated or tested).

If your definition of "deep" is 5% or less of S.O.C. , that would be correct.

As such, for the practical user. i.e. the OP in this thread, "often discharging the battery deep / low (5-10%, or until SMC involuntary shutdown) is demonstrably, undeniably, and irrefutably harsh on the battery and causes premature chemistry change & destruction of the battery".

SMC involuntary shutdown occurs at a point at which deep discharge has occurred as implied and meant battery longevity reduction if often repeated.

From actual battery experts:

"Low or deep discharging of a lithium cell is 10X worse than slow wear"

"One deep cycle wears down the cell as much as dozens of shallow cycles"

kurt hahn1

I haven't seen the video either, and wont speculate on how valid it is in whole, however as per the one point from said video you mentioned:

He says it's extremely harmful to empty a battery and let it sit in that state (that's quite well known).

A: You're right, its well known (mostly).

B: Correct, its harmful to drain it low, ....and worse still to drain it low and let it sit, and thereby deplete to actual 0% S.O.C.

C: All battery experts agree that draining a battery to a "deep discharge" state is contra-indicated.

As Im sure you're aware, if you drain the battery to say 10%, and let it sit, it will unquestionably self-discharge on its own down to 0 (depending on heat and humidity) and that its horrible on the battery.

As to "deep discharge", you can ignore any semantics from anyone. The "20% rule" is that from actual battery experts, and is a golden rule to follow pertaining to Lithium use.

Realistically however in normal use, nobody is going to use their battery exactly between 20 and 85%, its just a rough guideline for ideal battery health long term.

Obviously, if you recharge the battery at X%, that remaining charge, ...it isnt lost, of course.

A charge cycle means using all of the battery’s power, whether that is at once, or over several shorter battery discharges and recharges.

Two examples for clarification:

As a first example, where one fully charged battery is discharged down to 10%, then fully recharged, then using 10% of that full charge, this counts as 1 cycle since the total of both discharges is 100% of a full charge of use.

In the second example, where one fully charged battery is discharged down to 40%, then fully recharged, then using 40% of that full charge, this also counts as 1 cycle since the total of both discharges is 100% of a full charge of use.

While both examples are that of a single charge cycle, the first example is more aggressive against the lithium battery chemistry than is the second example. In short, collective overall gentle shallow or mid-range draining of your lithium battery is a better use condition than is the first example of deep-draining of the battery. While both are quantitatively identical as a single charging cycle, they are wholly different qualitatively on the battery chemistry, which is directly related to its ultimate longevity and health.

In short, it is the near and mid-term life of the battery as relates to its proper care (or lack thereof) that is to be looked after.

kurt hahn1 wrote:

After reading all this, I *think* that maybe I could have deep discharged it too many times, because I wasn't aware that this could be a problem

Yes, dropping the battery low until the the battery 'squeaks' is rough on lithium cells.

Gaming on battery causes rapid discharges and is something most people arent aware of. If you did a lot of that, then thats a major contributing factor.

see here, example:

https://discussions.apple.com/thread/6034488?start=0&tstart=0

Lithium batteries like to be gently drained (not referring to low), not 'dumped dry' quickly and often as is necessitated when playing games on battery which pulls a lot of power for graphics.

Lot of gaming should be played on charger.

As mentioned above, Apple’s adaptive charging system "puts the brakes" on serious battery depletion and shuts the computer down, however that only mitigates part of the damage (the very serious part).

However, of course, much "minor serious" is accumulative on battery damage.

kurt hahn1 wrote:

it doesn't really look like Apples software prevents the user from deep discharging the battery

It does prevent the awful deep discharges. But as said, it doesnt prevent lots of 'bad discharges' which accumulate, and are never reversible.

However NO software, Apple or otherwise can prevent self-discharging of the battery when shelved.

You put it away on a low charge and let sit, it will drain and drain and compound the ill health of the battery.

Semantics on the % level of the definition of "deep" doesn't help you or any other real world user.

Just call it "often 10% or less is very bad" and then this is wholly an accurate statement to follow.

Easy way to remember battery treatment is, - Treat your lithium battery like a tomato, dont drop it (low), and dont squeeze it.

Peace

With PV on this, definitely possible to damage a MBP/MBA Lith-ion battery due to multiple deep discharges. Seen it on these forums and have experienced it once in the past (post-calibration era). Regards.

Then download a great free APP from the App Store.

FOTOR

Download the free battery app off the web. Coconut battery

http://www.coconut-flavour.com

Peace.