where are those fuel-cell powered laptops? http://techland.time.com/2011/12/23/apple-posits-fuel-cell-p...
The De-evolution of My Laptop Battery
121–130 of 148 posts
Re: The De-evolution of My Laptop Battery
#122Earlier quoted context omitted.
I believe Apple charges $199 for a battery replacement, which is definitely not cheap, but might be worth it if you were still happy with the rest of the machine. I'm not sure how long it takes them to do it, though. I'd expect they'd continue to offer that service for quite a few years to come. As other posters have mentioned, it seems to me like the glued-in batteries don't rapidly decline like the old ones did. I…
Apple batteries cost no more than competitors' batteries, and that includes getting them exchanged. Sure, it's annoying you can't do it yourself, but that's about the extent of the downside. Of course you cannot get third party batteries … but surely no one would get those for laptops amyway. (Well, some batteries are not yet glued in, so those can easily be replaced. But i don't think getting third party batteries i…
I used a third party battery with double the previous capacity for an Asus laptop without any issues
Re: The De-evolution of My Laptop Battery
#123WHOA!! 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…
The really dumb thing is that, as far as I can tell, a battery's controller generally counts a "cycle" as "started discharging, started charging", regardless of time in between. At least, that's how it was with my MacBook a few years ago. Unplug, plug in, cycle count increases. The crappy thing about that is warranties. Apple, for example (at least last I checked; I don't use a Mac anymore) , would replace a battery…
If you read the documentation a cycle is considered a full charge and discharge of the battery. It doesn't have to be discharged or charged fully, but when you've charged the full capacity of the battery and discharged that same amount, that's a cycle.
Re: The De-evolution of My Laptop Battery
#124Not an Apple consumer here, but my netbook battery only lasted about one year, and I attribute this rapid failure to my use of a cheap, (I live off-grid) modified sine wave, voltage inverter, but I have no valid proof of my assumption. As likely a cause for the battery failing to take a charge is the fact that I often ran the netbook until the battery charge depleted to the point of shutting the PC down. When I bough…
To confirm or disprove your idea, you could look at the output of the battery charger rather than the input to it. In general, AC-DC converters are pretty insensitive to the harmonic content of the AC input because their role is to remove any harmonic content they do find. They do this with huge low-pass filters with corner frequencies well under 1Hz, whether the charger is either linear (unlikely) or switching (much…
Interesting, but does using a DC to AC inverter change anything?
I've noticed that cell phone batteries also failed prematurely when I had the modified sine inverter.
Do you mean that if my charger was operating with less efficiency due to modified sine wave input then my batteries were not likely to be affected?
Re: The De-evolution of My Laptop Battery
#125WHOA!! 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…
> opposite of Nickel Metal Hydride Fully discharging any battery isn't good for it. NiCd had the particular problem of "memory" developing though, so going through a full discharge cycle was necessary to prevent the memory forming. It wasn't good for the battery, but it was better than letting the memory develop. I'm not aware of NiMH developing a memory, so that wouldn't be a good thing to do with NiMH either. I alw…
There are two types of discharge states - typically "fully discharge" implies within the application the battery was designed, not completely dead. For example, a car battery is fully charged at 12.6v, but discharged at 11.2 (or somewhere around there). There is still lots of capacity left, but dead for the use of cranking over an engine. NiMH typically has a very fast self discharge rate - letting these dip well below the operational capacity level will be much more detrimental than just letting your drill die after prolonged use.
NiMH has memory too, but not as bad as NiCd. We always suggested allowing NiMH to fully discharge time to time, but we never suggested keeping a phone on its base constantly.
Both these types of batteries need to be primed properly - full discharge/recharge the first few cycles. (Not sure about the new pre-charged NiMH, like Eneloop)
Memory builds faster when left in a discharged state.
Cadex machines can be used to reverse memory, to an extent.
I'm speaking from memory from 6 years ago. Hopefully I didn't mess up too much =P
Re: The De-evolution of My Laptop Battery
#126WHOA!! 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…
The really dumb thing is that, as far as I can tell, a battery's controller generally counts a "cycle" as "started discharging, started charging", regardless of time in between. At least, that's how it was with my MacBook a few years ago. Unplug, plug in, cycle count increases. The crappy thing about that is warranties. Apple, for example (at least last I checked; I don't use a Mac anymore) , would replace a battery…
A battery engineer would view that as a cycle, but Apple does not.
Funny thing is, I don't imagine any li-on battery lasting 1000 cycles after full discharges! Good warranty or what!?
Re: The De-evolution of My Laptop Battery
#127WHOA!! 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…
Interesting. Last I looked, the supposed optimal way to prolong a Li-Ion battery was to not let it get below 50% (ie, plug it in to charge when it gets to 50%). I think it was from a link off of Lifehacker a while back. Storing at 40-60% was recommended as well. I do typically use a smart charger on my NiMHs, and make sure to "break-in" (full discharge -> trickle charge to full -> full discharge -> trickle charge to…
I too read the 50% capacity rule, but I read it in a very professional battery book, but I remember the gains were very minimal. Something like 10-15% increase in lifespan. When a battery is only lasting 2-3 years as it is, that is less than half of a year.
Going back to my link, it looks like 50% is the sweet spot in the DoD chart; multiplying the number of discharges by the DoD results in 50% DoD being the highest return on capacity.
But...also remember in an application where you can use the device while its charging changes the concept of maximizing life span. I don't believe the act of discharging will avoid shortened lifespan, but rather it avoids degradation on the battery CAUSED by discharging itself.
Batteries hurt my brain...
Re: The De-evolution of My Laptop Battery
#128If 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.
2012 Macbook Air: Cycles: 138 Health: 83% Is this replacement worthy? What am I doing wrong?
Without knowing what their exact boundaries are your numbers don't look great. Most people here seem to have Airs, but to compare with my Pro:
730 cycles, 92% capacity after 27 months (mid-2011).Re: The De-evolution of My Laptop Battery
#129I've set my thinkpad to 'start charging' when below 40% & 'stop charging' when it reaches 60%. I use it with AC power plugged in while the battery floats ~40-60% charge level. Once a month I power cycle it to re-calibrate the battery. It's been going good for the past 3 years. Shows 500 cycle count with 80-90 hrs/week usage & ~80% capacity.
Re: The De-evolution of My Laptop Battery
#130Earlier 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.
Not to support the "evil executives" hypothesis---obvious market(ing) forces are a sufficient explanation for the dominance of LiCoO2---but I would easily opt for a laptop that offered an LiFePO4 ("iron phosphate" [0]) option. The drawback would be slightly reduced initial capacity; the advantage would be much greater cycle life. Also, less spontaneous combustion.
[0] http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery