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The De-evolution of My Laptop Battery

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Re: The De-evolution of My Laptop Battery

#61

Post by [deleted] »

Arjuna wrote: post #14
voidlogic wrote: post #7

>letting the battery cycle* Wait- I thought that was for NiCd batteries and Li-ion batteries where suppose to always be topped off? Furthermore going below 15-20% charge hurts their max charge level? *By cycle he means running it down and charging it up?

The official advice is: "Apple does not recommend leaving your portable plugged in all the time. An ideal use would be a commuter who uses her notebook on the train, then plugs it in at the office to charge. This keeps the battery juices flowing. If on the other hand, you use a desktop computer at work, and save a notebook for infrequent travel, Apple recommends charging and discharging its battery at least once per…

[deleted]

Re: The De-evolution of My Laptop Battery

#62

Post by cliveowen »

sengstrom wrote: post #57

How do you even measure max capacity of the battery? Is it by keeping track of the current balance or is there some other direct physical way to do it? Measuring once per minute seems like massive overkill for a property that changes on a timescale of months, but the interesting question to me is - does it do anything to the life of the battery?

Mac OS X makes the stats available directly from the battery.

Re: The De-evolution of My Laptop Battery

#63

Post by mmanfrin »

YooLi wrote: post #4

If your cycle count is 223 and you are nearing 80%, then your battery is defective, plain and simple. Apple will replace it. It's happened to me a couple times and Apple took care of it with no hassles.

How do you prove this to Apple? I have a 1year old MBA that is definitely not getting anywhere near 3 hours on battery, let alone the 7 they advertise.

Re: The De-evolution of My Laptop Battery

#64

Post by JimmaDaRustla »

WHOA!!

Huge mistake here - he says he cycles his battery! DO NOT DO THIS TO LITHIUM ION BATTERIES! Lithium Ion will last longer by NOT allowing the cells to be fully discharged!

This is the opposite of Nickel Metal Hydride and Nickel Cadmium - these types of batteries DO require a full discharge and full recharge in order to provide a longer life.

In addition, the number of discharges, the temperature, etc all come into play with lithium ion. These thinner laptops are actually lithium ion polymer, where the materials are folded into packs...much more susceptible to the elements, like heat.

Disclaimer: Spent 3 years in the battery field. http://batteryuniversity.com/learn/article/how_to_prolong_li...

Edit: Just want to point out that charging a laptop while using it could potentially create more heat, degrading the battery. I'm not sure what is more damaging - letting the li-ion battery drop below 70%, or charge it while the laptop is being used. So many variables!

Re: The De-evolution of My Laptop Battery

#65

Post by thehme »

humm, I suppose I should not be too upset then about my Mac Book Pro's battery. It is now a little over 3 years old and I just hit the 500 battery cycles mark this week, about the same time that I noticed my trackpad is no longer working properly. I have had the computer for a while and have not used extensively for over 1 1/2 yrs (have work computer), so I am unsure what it could be, but think it may be the battery. This year we have had a hot weather in the East Coast and my laptop sit out in the changing weather (can't leave the AC on for it), so this may have impacted the battery's lifetime. In general, I can just add that for moderate average use, my Mac Book Pro's battery has lasted quite a bit, but would have liked it to last closer to the 100 cycles promised by Apple's system specs.

Re: The De-evolution of My Laptop Battery

#66

Post by lysol »

mmanfrin wrote: post #63
YooLi wrote: post #4

If your cycle count is 223 and you are nearing 80%, then your battery is defective, plain and simple. Apple will replace it. It's happened to me a couple times and Apple took care of it with no hassles.

How do you prove this to Apple? I have a 1year old MBA that is definitely not getting anywhere near 3 hours on battery, let alone the 7 they advertise.

The cycle count is in System Information, as is the age of the system. Their own docs say it should get 1000 cycles before you're down to 80% of the original capacity. They have diagnostic tools to test it at the Genius Bar and measure the actual full capacity of the battery.

Re: The De-evolution of My Laptop Battery

#67

Post by nekopa »

cinquemb wrote: post #58

Are they're people out there that replace their own MB(P|A)? Is it possible? I know there are hacks out there to take apart and fix chargers (I did it myself).

How did you fix your charger? I have always thought that we (users) shouldn't have to worry about charging, over-charging, stretching the battery (I have honestly heard people talking about this) and so on. We have the tech to make smart chargers, why aren't they here yet?

{OT: has anyone else thought why we don't have a full bay size laptop battery that can be put inside a desktop for those times the power goes out, but we don't want/need a UPS?}

Re: The De-evolution of My Laptop Battery

#69

Post by msrpotus »

mmanfrin wrote: post #63
YooLi wrote: post #4

If your cycle count is 223 and you are nearing 80%, then your battery is defective, plain and simple. Apple will replace it. It's happened to me a couple times and Apple took care of it with no hassles.

How do you prove this to Apple? I have a 1year old MBA that is definitely not getting anywhere near 3 hours on battery, let alone the 7 they advertise.

You can download Coconut Battery [1], which will show you the battery capacity and number of cycles.

1: http://www.coconut-flavour.com/coconutbattery/

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