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The De-evolution of My Laptop Battery

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Re: The De-evolution of My Laptop Battery

#71

Post by berkut »

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.

Really? I got a 2006 MacBook Pro in Dec 2006, and each year I had to buy a new battery from Apple as it generally got down to 30-40% capacity.

First time it happened (and was still under warrantee), I took it into Apple, and they said it was normal, and they only replaced batteries if it was defective.

I went through 5 batteries until I got a 2011 MacBook Pro.

Re: The De-evolution of My Laptop Battery

#72

Post by rednukleus »

acheron wrote: post #59
sixothree wrote: post #20

Is this guy really a developer? I can't imagine using a single 15" monitor to accomplish anything at a productive pace.

Indeed. It's a good thing there were no developers between 1970 and 2000, and all programs spontaneously arranged themselves via xkcd butterflies until monitors arrived that allowed for development.

15" 4:3 monitors were standard before year 2000. You have to go back to probably the early 90s before standard monitors had less real estate than a 15" widescreen. Of course resolutions and panel quality have increased since then, which mitigates the problem of working off a laptop monitor. Personally I find im far more productive on a 24" monitor than a 14" laptop screen, but its not impossible.

Re: The De-evolution of My Laptop Battery

#73

Post by sengstrom »

cliveowen wrote: post #62
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.

Yes, but how does it arrive at the number it reports?

Re: The De-evolution of My Laptop Battery

#74

Post by thehme »

JimmaDaRustla wrote: post #64

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 i…

I believe you are correct on the "cycling the battery", which I believe you want to avoid, so that you battery will be able to charge fully for longer.

"A charge cycle means using all of the battery’s power, but that doesn’t necessarily mean a single charge. For instance, you could listen to your iPod for a few hours one day, using half its power, and then recharge it fully. If you did the same thing the next day, it would count as one charge cycle, not two, so you may take several days to complete a cycle. Each time you complete a charge cycle, it diminishes battery capacity slightly, but you can put notebook, iPod, and iPhone batteries through many charge cycles before they will only hold 80% of original battery capacity." - http://www.apple.com/batteries/

http://support.apple.com/kb/HT1519

Re: The De-evolution of My Laptop Battery

#75

Post by ferongr »

JimmaDaRustla wrote: post #64

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 i…

Wouldn't all modern power management ICs operate the laptop directly from the power supply while float-charging the battery resulting in negligent amounts of heat?

Re: The De-evolution of My Laptop Battery

#76

Post by gz5 »

glhaynes wrote: post #35
gz5 wrote: post #28

Earlier quoted context omitted.

imo very conscious decision on part of Apple (and PC makers) to provide short battery half lives, rather than spending more money to deal with the size and heat/cooling constraints of laptops, especially the thin lightweight variety. not only saves them money short term, but helps push users to new versions before they really need to jump...

Is there evidence for this? Is there a better battery tech the entire industry should be using instead? Seems unlikely.

is it possible the better batteries don't (generally) exist because the manufacturers are not motivated to invest the r&d in the first place? i certainly have had too many laptops that don't provide optimum cooling (and they could, at more expense) when we know heat is a limiter of battery life.

Re: The De-evolution of My Laptop Battery

#77

Post by cinquemb »

nekopa wrote: post #67
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,…

One of the wires broke inside of the magsafe. So with some pliers I opened it up, then cut the broken part, strip the tip to expose the connection, reconnected it (tested it and put some electric tape around it to be sure), and assembled it back together with tiny amounts of hot glue on the edges. I wish they designed things so they can be taken apart easier. I'm not sure if this is really "fixing the charger" but some people decided to solder off the tips connection to the board, cutting the bad part, and soldering it back (I didn't want to do that much work).

I think for most users, they shouldn't have to worry about it, but I feel like there should be the ability in the hardware/software for users to have the ability to maintain/mod their own systems if they please.

Re: The De-evolution of My Laptop Battery

#78

Post by gz5 »

tomkarlo wrote: post #53
gz5 wrote: post #28

Earlier quoted context omitted.

imo very conscious decision on part of Apple (and PC makers) to provide short battery half lives, rather than spending more money to deal with the size and heat/cooling constraints of laptops, especially the thin lightweight variety. not only saves them money short term, but helps push users to new versions before they really need to jump...

Can you point to data showing competitors that are doing it better? Seems like the battery life problem impacts everyone pretty equally, and the batteries being used inside Macbooks are pretty similar to those used by every other manufacturer.

agree, this is not specific to macbooks. bottom line is today's batteries only achieve (relatively) limited charge/discharge cycles and i don't believe (could certainly be wrong) there is much business motivation to improve that.

Re: The De-evolution of My Laptop Battery

#79

Post by ajross »

ferongr wrote: post #75
JimmaDaRustla wrote: post #64

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 i…

Wouldn't all modern power management ICs operate the laptop directly from the power supply while float-charging the battery resulting in negligent amounts of heat?

Yes to the former, but (hopefully a real battery expert can chime in here) my understanding is that lithium-ion batteries cannot be float/trickle charged safely. Their internal resistance is too non-linear and it's too easy even with a "full" battery to provide a voltage that will sink dangerous amounts of current and overheat.

All lithium ion technologies I'm aware of require active current and temperature monitoring.

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