battery & load cycles ≠CONFUSION

i am a relatively new user of macbook mid 2012 (well sort of, it has been only 14 weeks as indicated in the pic) http://i.imgur.com/6LH5mn4.png
14 weeks
52 cycles

throughout this time i have been charging it to 90% and letting it go as low as 20%
learnt about the method of cycles, 50% one consumes today and the other 50 the very next day will day a single cycle, while other users keep the cycle load as low as possible, It has dawned on me that I have been over-adding cycles
basically I use my mac like 5, 6 or even 8 hours a day
some sites say that I shouldn`t keep it plugged and let it use on the battery, others say frequent use on battery can shorten its battery`s life
like really I don`t know what the best best thing to do(((

No need to worry mikaju,

Discharge cycles quoted by manufacturers are usually 'worst case' from 100% Depth of Discharge (flat) because they have no way of knowing how you are going to use your machine.

The figures are generally based on how many cycles the battery can deliver before it's capacity drops below 70%, at which point the thing is not cutting the mustard and will likely need replacing (it won't fail...just keep a poor state of charge).

Charging from 50% DoD can give you upwards of 3 times the number of discharge cycles quoted.

Keeping a full battery at high temperatures will dramatically shorten it's life, so environmental conditions are equally as important.Storing it it fully charged in hot car, or using it plugged in on a duvet over your lap are not good practise.

Equally, you won't cause much damage keeping it plugged in when in use because the charger stops when the battery is full and will only re-engage when it's voltage drops.

That said the trick with Lithium Ions is to keep them moving, so if it were me I would partially discharge on battery every now and again.

Charging from 20% (80% DoD) is the opposite of what you should really be doing though. Do it the other way around (charge from 80% or 20% DoD) and you will see the benefit.

pendlewitch said:

No need to worry mikaju,

Discharge cycles quoted by manufacturers are usually 'worst case' from 100% Depth of Discharge (flat) because they have no way of knowing how you are going to use your machine.

The figures are generally based on how many cycles the battery can deliver before it's capacity drops below 70%, at which point the thing is not cutting the mustard and will likely need replacing (it won't fail...just keep a poor state of charge).

Charging from 50% DoD can give you upwards of 3 times the number of discharge cycles quoted.

Keeping a full battery at high temperatures will dramatically shorten it's life, so environmental conditions are equally as important.Storing it it fully charged in hot car, or using it plugged in on a duvet over your lap are not good practise.

Equally, you won't cause much damage keeping it plugged in when in use because the charger stops when the battery is full and will only re-engage when it's voltage drops.

That said the trick with Lithium Ions is to keep them moving, so if it were me I would partially discharge on battery every now and again.

Charging from 20% (80% DoD) is the opposite of what you should really be doing though. Do it the other way around (charge from 80% or 20% DoD) and you will see the benefit.

Click to expand...

first of all i am a mac-noob (it has been a while since i switched from windows to mac) so i do apologize if i may ask you to paraphrase certain lines you mentioned, i do appreciate that you took some time and provided me with insightful feedback

Charging from 50% DoD can give you upwards of 3 times the number of discharge cycles quoted. this line was totally confusing, sorry could you please clear up exactly what you meant

Equally, you won't cause much damage keeping it plugged in when in use because the charger stops when the battery is full and will only re-engage when it's voltage drops.
you mean as long as i am at desk working for several hours non-stop, it is fine to keep it plugged and that the battery will itself go idle though it is plugged (fluorescent green line)
and that i could give it a break, only occasionally by discharging AC and using it for a while on battery

Charging from 20% (80% DoD) is the opposite of what you should really be doing though. Do it the other way around (charge from 80% or 20% DoD) and you will see the benefit.
judging from this one, i shouldnt let it dwindle to 20% but rather plug the AC once the battery gets to 80% (so that it will reach 100 and i am gonna keep it plugged till i make sure that there is some necessity to unplug and run it on battery again, not less than 80)

sorry if i sound too exhaustive

Hi,

No problem. It is a very confusing issue and a lot of people struggle with the concepts. You actually do have some good awareness because you understand what a charge cycle is so all you need to do is trust that there are some simple things that you can do to keep your battery healthy.

Studies have shown that smaller charges are better for your battery than larger ones. They place less stress on the battery. The table below is a summary from a source that I often use to demonstrate this phenomenon courtesy of Cadex.

Yes, what I am saying is that there is no harm in keeping it plugged in when in use. Personally I wouldn't leave it plugged in when not in use, and I would remove the charger and run the machine on battery for small periods occasionally.

Yes, I understand that it can be quite difficult to always be near an AC socket but charging from smaller depths of discharge (not always from 20% DoD, could be 10% could be 25% or 50%) is always better than charging from a greater DoD.

Here the confusion can arise with the terminology used. The fuel gauge on a battery is actually a representation of the battery's 'State of Charge' or SoC and the Depth of Discharge or DoD is the inverse of this. So therefore 20% Depth of Discharge becomes 80% State of Charge on the battery's fuel gauge.

pendlewitch said:

Hi,

No problem. It is a very confusing issue and a lot of people struggle with the concepts. You actually do have some good awareness because you understand what a charge cycle is so all you need to do is trust that there are some simple things that you can do to keep your battery healthy.

Studies have shown that smaller charges are better for your battery than larger ones. They place less stress on the battery. The table below is a summary from a source that I often use to demonstrate this phenomenon courtesy of Cadex.

Yes, what I am saying is that there is no harm in keeping it plugged in when in use. Personally I wouldn't leave it plugged in when not in use, and I would remove the charger and run the machine on battery for small periods occasionally.

Yes, I understand that it can be quite difficult to always be near an AC socket but charging from smaller depths of discharge (not always from 20% DoD, could be 10% could be 25% or 50%) is always better than charging from a greater DoD.

Here the confusion can arise with the terminology used. The fuel gauge on a battery is actually a representation of the battery's 'State of Charge' or SoC and the Depth of Discharge or DoD is the inverse of this. So therefore 20% Depth of Discharge becomes 80% State of Charge on the battery's fuel gauge.

Click to expand...

you could`t have explained it better
immense thanks
all is superclear now
cheers mate