laptop battery discussion/how to get longest life

[Perris Calderon]

had conversation with a friend and we got into battery tech, to which we both had differant bits of information each respectively did not know

I wiki'd to double check his info and he was spot on, mine was too but everyone on a laptop or portable device should understand lithium ion effective depletion so they can get more life out of their very expensive battery

here's the wiki link and here's the pertinent info abridged;

the li-ion battery depletes for various reasons but the one reason most people believe it depletes doesn't happen

it does not deplete with discharge, it depletes with re-charge!

a deposit left by the charge cycle (not the discharge cycle) will increase resistance, obviously the more deposits the more the resistance, thus a charging depletion

in other words, it's not a good idea to leave your laptop plugged in with the battery in place if the battery already has a charge

if you need the greater performance mode while plugged in and also want best use out of your battery, remove the battery while on the grid!!!

now, the lower the voltage the less you notice charge depletion so it's not an important consideration on small lower voltage devices


I will get in touch with my contacts at microsoft and see why they do not have a "no charging mode" designed into the operating system or hardware

that's not the only thing but it's most of it, I had read tech reports that informed me the battery is time depleted and that's true but not nearly as important as charge depletion

for time depletion the battery loses 20 percent of it's capacity every year, but only if it's at full charge!

it depletes less over time according to the level of charge!!!

in other words, the longer the battery enjoys full charge the shorter the duty cycle!!!!! (counter intuitive and an oposite effect when compared to wet cells, I don't know about nicads though)

my batteries seem to last about a year every time and I just found out, this is because they are ALWAYS charged or always being charged!!!

so my battery is always being time depleted to the fullest and charge depleted constantly


interesting that

 

[Perris Calderon]

Re: interesting/important battery info

important stuff here for laptops, I think it should get a sticky but I do love my own writing so you guys decide

 

[ming]

Re: interesting/important battery info

It's interesting to read the details of this actually. I've only known that the more you recharge a battery without fully discharging it first will result in a shorter battery life.

Not only does this article apply to Laptops, it applies to a large majority of mobile phones as well.

Does this only apply to Lithium Ion batteries only, or does it include other Lithium batteries as well, such as Lithium Polymer?

 

[Perris Calderon]

Re: interesting/important battery info

It's interesting to read the details of this actually. I've only known that the more you recharge a battery without fully discharging it first will result in a shorter battery life.

Not only does this article apply to Laptops, it applies to a large majority of mobile phones as well.

Does this only apply to Lithium Ion batteries only, or does it include other Lithium batteries as well, such as Lithium Polymer?

it's not so much phones I don't think since they use less juice and resistance isn't as affected, and they're not always plugged in like most laptops seem to be used as desktops

as far as li-ion, there isn't the "full discharge needed to avoid charge memory problems" that nicads have, it's simply how many times you charge the battery and for how long

obviously if you wait till it's depleted you are going to get fewer deposits but it's not the big hit a nicad gets

on a li-ion you shouldn't deliberately deplete your battery simply because you are going to charge it, (the refresh you do before you charge a nicad), that will do more harm then good, you're better off just charging it but you are better off over all using till near dead and then when the battery is fully charged but you want to stay plugged in you should remove said battery

interesting stuff

 

[LeeJend]

Re: how to get longest life from laptop battery

Technical rebuttal – courtesy of last weeks 3 day energy storage symposium and answers from a key player in the SAE Battery standards committee.

The li-ion battery depletes for various reasons but the one reason most people believe it depletes doesn't happen it does not deplete with discharge, it depletes with re-charge!
Terminology is incorrect. All batteries deplete from discharge. Battery energy storage capacity degrades based on problems with non-reversible chemistry reactions during charge or discharge. Sufficient degradation results in the battery no longer being able to provide enough voltage for long enough to be useful. Degradation also occurs from increased resistance of the anode and cathode from depositing out of contaminats in the electrolytes and reduction in effective surface area.

a deposit left by the charge cycle (not the discharge cycle) will increase resistance, obviously the more deposits the more the resistance, thus a charging depletion
Deposits are left on both the battery anode and cathode during charge/discharge. Since you can not have discharge without charge assigning degradation to one instead of the other is misleading. The battery charges job is to prevent over charge which leads to catastrophic failure in any rechargeable battery. Battery resistance is increased which increases self heating and lowers output voltage both of which factors affect how much of the stored charge is usable.

in other words, it's not a good idea to leave your laptop plugged in with the battery in place if the battery already has a charge
Incorrect. EVERY rechargeable battery charger senses when the battery is full and stops charging. If they didn’t the batteries would burst/explode/catch fire depending on the type of battery. LiIon battery failure would occurs minutes of reaching an over charge condition.

if you need the greater performance mode while plugged in and also want best use out of your battery, remove the battery while on the grid!!!
A meaningless act and increases risk of data loss during power drops outs. See above charger operation explanation.

now, the lower the voltage the less you notice charge depletion so it's not an important consideration on small lower voltage devices
Totally incorrect. LiIon uses a 3.6V cell stacked in series to get higher power for applications like laptops, electric cars, etc. One low voltage cell (MP3 Player, Cell phone (smart phones may stack 2 cells)) acts the same as multiple cells stacked to power a laptop. This urban myth may have originated since stacked cells in LiIon batteries need to have cell charge balancing circuitry to assure each cell charges equally to the others (not required ofr single cell LiIon batteries or for NiCd/NiMH). If there is not cell balancing some cells will end up undercharged and others overcharged over multiple charge discharge cycles. Explosion and fire will result.

I will get in touch with my contacts at microsoft and see why they do not have a "no charging mode" designed into the operating system or hardware
Superfluous. Charging is controlled in the charger hardware. Software is not involved.

that's not the only thing but it's most of it, I had read tech reports that informed me the battery is time depleted and that's true but not nearly as important as charge depletion
Correct terminology is cell leakage or self discharge. LiIon is one of the battery chemistries less subject to self discharge. NiCd is the worst (days-weeks), NiMH (Month) is better and the newer NiMH type are much better (pushing a year). LiIon still leads the pack.

for time depletion the battery loses 20 percent of it's capacity every year, but only if it's at full charge! A battery will lose it’s charge regardless of state of charge. It is recommended by the professionals to keep any battery full charged for storage.

it depletes less over time according to the level of charge!!!
in other words, the longer the battery enjoys full charge the shorter the duty cycle!!!!! (counter intuitive and an opposite effect when compared to wet cells, I don't know about nicads though)
Any battery has less to loose if it is not charged so storing partially charged batteries does not buy you anything. Storage out of a device helps extend charge shelf life because all devices made today never turn off. They always have keep alive circuitry running for internal clocks.

my batteries seem to last about a year every time and I just found out, this is because they are ALWAYS charged or always being charged!!!
Incorrect the worst degradation to LiIon is from deep discharge cycles. Never let LiIon get below 50% charge, irreversible chemical reactions occur.

so my battery is always being time depleted to the fullest and charge depleted constantly
Congratulations. The battery manufactures like people to trash batteries as fast as possible. Full discharge was recommended for early NiCd to prevent formations of large moleculesls (vs smaller molecules that hold more energy). This was called memory though that term is incorrectly used for many similar effects. Newer NiCd and NiMH do not exhibit this problem. LiIon should not be discharged below 50%. I try to keep my laptop above 80%.

My laptop and small gadget LiIon batteries are all over 3 years old and still provide the same life as when new.

If you ever want to fry your brain sit and listen for 8 hours to Dr’s of chemistry and physics bubbling over enthusiastically about how exciting it is to find a new polymer that allows more efficient bonding of Li Ions to anodes and cathodes resulting in a few percent increase in battery capacity. My head still hurts…

 

[Perris Calderon]

Re: how to get longest life from laptop battery

Technical rebuttal – courtesy of last weeks 3 day energy storage symposium and answers from a key player in the SAE Battery standards committee.

interesting information and good points

hard to follow the rebutts though, it would help if you put my text in quotes

you make great points and I suppose your simposium has more current theory then the wiki however a few counter points to your points

taking out the battery affects data security especially since the laptop can easily be disconected from the grid however most desktops do not enjoy off grid power protection and the danger is not that far removed from a desktop, except of course for the grid port on the laptop but that can easily be secured with no added concern over the exact scenario most people have with their desktop

EVERY rechargeable battery charger senses when the battery is full and stops charging.

while it's true a laptop will prevent overcharge on a fully charged battery, this fact is mitigated since (your point), the unit always uses power the battery is always in a state of charge discharge, you want as few charge situations as possible, those re-charge events are not good

now, even if I'm incorrect and there's no "discharge/charge" going on in a fully charged on the grid laptop, never the less a fully charged battery permanently depletes far faster then a partially charged batery and that's the real point

imo there should be a switch so it either charges or discharges for given levels of charge and a user can choose between self regulated or hardware regulated

unless the wiki link is wrong, and I double checked multiple sources and the information is pretty spot on, also look to his foot notes, the battery permanently degrades according to the level of charge, it permanently time degrades more when fully charged then discharged. this is very important to know when developing your charge discharge strategy

once again according to the footnotes you should not store your battery at 100 or 80 percent (your prefernance) but neither should you store it too low, (my previous recomendation, now amended because of your excellant post)

the footnotes and other sources usually recomend 40 percent charge for best life/protection on storage

I suppose my phone batteries last longer then my laptop because my phone batteries are not always being charged, my laptop batteries are

in addition, my phone batteries enjoy a far slower charge, the faster the re-charge the more damage and that might be the main reason

All batteries deplete from discharge.

according to the links, this isn't true as far as practical degradation, while there might be some degradation on discharge the majority happens on re-charge, this is a significant differance and it's a big one

Battery energy storage capacity degrades based on problems with non-reversible chemistry reactions during charge or discharge

as I pointed out above it's either or, sometimes both but in the li-ion example the marjority of nonreversable chemistry happens on re-charge not discharge, that's a quite significant distinction

there is a reason you need to understand when the battery is degrading, charge/discharge and I give a practical example at the end of this post

Since you can not have discharge without charge assigning degradation to one instead of the other is misleading

the actual facts are more then informative and more then academic they are practical, the actual knowledge of specifically when degradation occurs will help create best charge/use strategy for longest performance on our personal use, that was my very point, you can determine best strategy when you know where the damage is being done the most, how and why

using that knowledge and the knowledge that the battery permanently depletes faster at full charge, then further multiplies that effect when you are re-charging is quite useful

you then take that knowledge and develope the best battery duty cycle strategy for our own persnal lifestyle

Any battery has less to loose if it is not charged so storing partially charged batteries does not buy you anything

of course it buys you something, if you are storing a battery at full charge you are permanently losing 20 percent capacity after a year, that permanent loss is far lower if the battery has a far lower level of charge

let's suppose it loses 20 percent of the charge level, therfore if you have the battery stored at 50 percent capacity it will still permanent capacity at the 20 percent rate but of that 50 percent with the remainging 50 precent left healthy, this is a far smaller loss then 20 percent of 100 percent

the worst degradation to LiIon is from deep discharge cycles. Never let LiIon get below 50% charge, irreversible chemical reactions occur.

this advise doesn't make sense as far as practical application and is probably wrong technically as well (link below the paragraph)

for the practical discussion;

you are on a laptop and you got that laptop for a reason, you use it till you are done and you get as much work done as possible according to your battery status, you don't consider charge level to 50 percent or some made up number you consider when you are going to lose the ability to work and then finish up with headroom

when you are working (or playing for that matter), you get as much done as possible or as much as you feel you have most productivity

in most of my cases, taking laptop that can be used for 2 hours and only using it 1 hour leaves you with a work scenario whence you have just become productive and have to stop, quite counter productive, I use my battery when off the grid for as long as I can to get the most productivity from my time

now for the technical point from one of the wiki foot notes;

Although lithium-ion is memory-free in terms of performance deterioration

that's important as stand alone but there's more;

batteries with fuel gauges exhibit what engineers refer to as "digital memory". Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery's state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate. (Read more in 'Choosing the right battery for portable computing'

he's not being precise, he is saying the fact that the battery experiences permanent degradation the battery self calibration does not know the state of degradation until a full discharge and recharge

this could result in your catastropic scenario where the battery thinks it is not discharged when it is and the battery will go into deep discharge and create more harm then had you discharged the battery for re-calibration

this calibration pretty much has to happen on a regular basis since the battery is always in a state of permanent degradation, (less so with lower charge)

also, something you are not considering is the fact that li-ion is self protected against deep discharge, it self regulates that and the battery becomes unusable till recharge even though there is adaquate charge to run the laptop, that's internal, it even goes so far as to set an internal trigger that prevents any use of the battery if it gets too low and the battery will succesfully be resett with specific tools if you get to it before it's totally depleted, I don't think you lose much at all going to full laptop discharge of a li-ion since it self regulates against deep discharge

more from the link after your quote;

Totally incorrect. LiIon uses a 3.6V cell stacked in series to get higher power for applications like laptops, electric cars, etc. One low voltage cell (MP3 Player, Cell phone (smart phones may stack 2 cells)) acts the same as multiple cells stacked to power a laptop. This urban myth may have originated since stacked cells in LiIon batteries need to have cell charge balancing circuitry

he disagrees;

Eventually, the cell resistance reaches a point where the pack can no longer deliver the stored energy although the battery may still have ample charge. For this reason, an aged battery can be kept longer in applications that draw low current as opposed to a function that demands heavy loads.

however there is a smaller effect depending on the type of li-ion you have;

The lower energy dense manganese-based lithium-ion, also known as spinel, maintains the internal resistance through its life but loses capacity due to chemical decompositions. Spinel is primarily used for power tools.

for those batteries it seems the type of discharge does not affect the duty cycle or ability of the battery to transmit said charge

he goes on with a time vs charge depletion rate and graph;

The speed by which lithium-ion ages is governed by temperature and state-of-charge. Figure 1 illustrates the capacity loss as a function of these two parameters.

which isn't as useful as li-ion technology improves

now about this;

Congratulations. The battery manufactures like people to trash batteries as fast as possible.

excuse me?

that's uncalled for, I use my battery according to my personal workload and pleasure, for my workload I have created a strategy that will get me an extra 6 months to a year of service from a battery

I do not nor care to go your route and use a battery and then stop when it reaches 50 percent charge, not only is this counter productive for battery life, it's counter productive for worklaod efficiency

or are you suggesting I buy two batteries so I can do the work of one battery?

furhter, you are far better off letting the battery discharge (to a certain level) then plug it in when there is a near full charge already on the battery

best thing to do in that case (if you are not concerned about data loss) is as I suggested, take the battery out, turn the laptop on and work from there

I personally have no concerns over data retention on laptops except for the work at hand, plus for me it's the same level of data security as a desktop that doesn't use battery backup

I will always remove the battery when I am on the grid and the battery already has anything more then 50 precent charge (unless I am counting on a full charge later)

ya I can kick out the plug or even disconnect fromt the laptop port inadvertantly but I don't see that much greater a risk of losing power over a desktop and the benefits far out weight the minor added risk of laptop over desktop, especially since data retention isn't a concern on my out of house laptops

on my inhouse laptop I will take further cautions to prevent loss of power but I will certainly be removing the battery for the added life

again, this is because the battery depletes more with a full charge then with a partial charge and that's how I'm going to keep my batteries in wait until I think I'm gonna need a full charge off the grid

perhaps the wiki and his footnotes need to be updated, perhaps I extrapolated where I shouldn't have

in any even, here's how the information can (and should) be used for my own laptop scenario, this scenario is in effect just about every work day by the way, it's not something I made up to suit the conversation

suppose I come to the coffe shop with a depleted battery

I can plug in and then go to work with a full charge however I will plug in at work also

this is going to add permanent full charge time depletion where none need to occur

instead, I am going to plug in with battery out, not charging the near depleted battery

when I get to work I will also not charge the battery, until the end of the day, whence I will plug in and have full charge for off the grid at the restaurant where no grid is available

I have saved time depletion for a full 9 hours, where if I did not consider the fact that the battery depletes on charge and then more becuase of full charge I would have used a completely counter productive strategy

this is the reason we need to know when the battery depletes most, (on re-charge and then time depleted if it has full charge)

in the end, batteries improve with ongoing research and these web sites I used for referance could be obsolete and I recognize the fact that a web site makes a claim doesn't mean it's accurate information

 

[X-Istence]

TLDR;

Actually, not true, but I almost never get to use that.

Perris when your laptop is on the grid as you call it, and your battery is fully charged your computer will pull power from the AC adapter rather than from the battery until the AC adapter is removed, at which point it will resume from battery. Thus when the laptop is plugged in there is no charge re-charge cycle going on.

Modern batteries have smarter technology that limits the amount of cycles that the battery has. For example my battery currently inserted in my Mac has the following information:

  Model Information:
  Manufacturer:	SMP
  Device name:	ASMB012
  Pack Lot Code:	0002
  PCB Lot Code:	0000
  Firmware Version:	0102
  Hardware Revision:	0500
  Cell Revision:	0200
  Charge Information:
  Charge remaining (mAh):	4248
  Fully charged:	Yes
  Charging:	No
  Full charge capacity (mAh):	4248
  Health Information:
  [b]Cycle count:	149[/b]
  Condition:	Normal
  Battery Installed:	Yes
  Amperage (mA):	148
  Voltage (mV):	12615

This battery is now 3 years old, and still holds about 80% of its original charge. Notice that it says that the battery has supposedly had 149 charge cycles, if your information was correct then it would be thousands by now. Also this laptop is disconnected from the power grid every single time I leave my home to go to school and or work. So 149 charge cycles in the last 2 years does not compute.

The new battery management systems take into account that people will be taking their laptop, spending maybe an hour or two without power, and then having them plug it back in. The circuitry does the balancing correctly so that until you undergo that same state twice it is not considered a charge cycle. Apple has some very awesome information about batteries available on their website: Apple - Batteries .

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.

None of the suggestions make sense. Storage of laptop batteries does not extend their life and may actually lower it since it will self discharge over time, which is worse for battery life than having it full charged using a trickle charger, also if the batteries get below certain voltages whereby they are so completely depleted that they won't even power an LED it can cause catastrophic disasters when they are plugged back in because of the chemical reaction. I have video where this was tested (by myself and some friends) somewhere, I will have to see if I can find it; violent explosions for the win.

Apple's suggestion:

For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time. An ideal use would be a commuter who uses her MacBook Pro 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 month.

Note how it says that you and I are the perfect people for the longest battery life? Unplugging the battery when done charging is definitely not on that list.

Here is what they say about storing laptop batteries.

If you don’t plan on using your notebook for more than six months, Apple recommends that you store the battery with a 50% charge. If you store a battery when it’s fully discharged, it could fall into a deep discharge state, which renders it incapable of holding any charge. Conversely, if you store it fully charged for an extended period of time, the battery may experience some loss of battery capacity, meaning it will have a shorter life.

That is also the reason why there is no option within Windows, Mac OS X, Linux, OpenSolaris, or FreeBSD to turn off battery charging. The circuitry within the battery and laptop is perfectly capable of dealing with that. Not letting it over-charge, under-charge, under-volt, heat-up (yes there are heat sensors in your battery to make sure that the cells are not getting too hot), and whether all of them are charging at about the same rate.

From the sound of your experience with batteries, it sounds like the manufacturer of said battery does a bad job, OR you have really used it daily in that one year whereby each time you fully depleted the battery to the point that the device shuts itself down. This is how I use my laptop, so I have no idea why you are already replacing it after a single year when I go three with mine.

Technical notes: I have done a lot of research and have taken apart many battery packs (have one lying around the house, the battery cells are orange, taped together with black electrical tape it looks like a bomb, especially since it has wires running to the control circuit) in an attempt to fully understand the design concepts behind the batteries and how they are charged mainly so that I could implement certain technology requirements into a project I was working on at the time that required a Lithium Ion batteries that were to be charged/discharged.

In the pictures, notice the grey tab sticking out from under the electrical tape, that is a heat sensor and fuse. If the temperature gets too high OR the charge current/current running through the battery gets too high it burns out for protection so that the battery cells don't explode. This particular model only has a heat sensor that can be checked by circuitry on the actual chip which is right next to the connector on the PCB. The battery in question had the traces on the PCB destroyed when the laptop had liquid spilled on it. The PBC six different actual chips (not yet microcontrollers, but still chips that have a very specific function), along with countless other parts to safely talk with the host computer to give feedback on charging (capacitors, resistors, thermistors, voltage regulators). The batteries themselves have been sitting discharged for so long that they have most likely lost all ability to hold a charge, and charging them would be a safety hazard.

Note: Electrical tape is my doing, only because I wanted the batteries to not break apart since they are spot welded together.

 

[Perris Calderon]

from what I've read so far that's good info existance, am at my sisters on her rig and need to spend more time on your post

macs obviously have far better battery management then windows, they always have though haven't they?

I am certain my laptop does not decide when to charge based on charge cycles, this charges every time I plug it in, if they are left over night it will again charge to full capacity

I have three vista laptops, the latest is 8 months old and the battery is down to abut half capacity, the first two have been through 2 and three batteries respectively

none of these batteries have given me more then a year service

in the past I just got a new laptop since the hardware was just about fried anyway or technology made the new laptop worth the investment

these laptops and the technology have held up fine so I've kept replacing the batteries

in any event, it's clear the info on wik and his footnotes might be eronious or badly written, I'm removing this as a sticky and leaving it as an ongoing discussion

I am getting 7 in a few days, and hopefully seven will manage the battery beter then my previous experience

I am certainly going to use the information from wiki and his footnotes to try to get more then one year out of a battery and I suppose I will renew this conversation if that strategy does indeed work

anyway, I enjoyed the conversation and I certainly do not claim those links are accurate, or have current information, it seems to me though the information will get me quite a bit more life out of my batteries
information

 

[X-Istence]

No, the laptop does no deciding on how to charge, but in lithium ion terms a charge cycle is considered depletion to 100% and then re-charging. When I come back home after having used my laptop for an hour my battery starts charging as soon as I plug in. So using to 50% on Tuesday, and then re-charging to 100%, then on Wednesday I use 60% and then I re-charge to 100%, that is considered a single charge cycle. The Apple page makes this pretty clear with their diagram and the way it is explained.

I quote again:

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.

Also power management has nothing to do with battery charging in any way shape or form. Power management is how the computer uses its resources, that includes turning the CPU down to a lower speedstep level, turning off extra unwanted resources (wireless, bluetooth, and others) and how often to spin down the hard drive, when to spin it up, how long the screen stays on after the screen saver kicks in.

Has nothing to do with charging batteries. The only way it has an effect on the battery is when you are on battery power when charging, once again, you are not using battery power at all.

MacBook Pro's in general are built with better power specifications and power usage across the board by limiting losses in various parts of the motherboards (the PCB layout for the MacBook Pro's is absolutely fantastic), and by having the ability to turn off various devices easily and on the fly as well as the OS being tuned better to use less resources overall when doing nothing (sitting idle), and for example not using 3D acceleration for the desktop when there is nothing 3D needing to be drawn thus the GPU not using more power or being constantly used. Aero is nice and all, but that is all being pushed to the GPU.

Also, while your Vista laptop probably has all these little blinky lights that tell you all kinds of useless information, those too require more circuitry to keep track of what is going on internally to give you external visual status indicators (hard drive activity, wireless activity, battery discharging, computer on, what else do they throw in these days?), considering that each LED takes 25 - 30 mA to turn on, you can calculate how much electricity you are wasting in stuff like that. Those LED's are not magically powered on and off.

 

[Perris Calderon]

charging damaging whether fully charged or not, the number of charge cycles does look like it is only changed effected as a whole and not per event...this I agree

the problem is with how long a battery stays at full strength, the lower the charge the less permanent depletion.

I"m sure if that information is correct then my new strategy will give me about 50 percent longer life...will not know for about a year though

using my phone for this post, pardon gramma or typos

be back next week

 

[wangping]

Please visit www.usa-laptopbattery.com for more available information of how to get more longer life for battery.

DELL 6000 battery specification

Type:Li-ionCapacity:11.1VVoltage:4400mAh Size:209.40 x 71.80 x 19.80 mmWeight:315gColor:Black

. Carefulness read narrate book of battery,use commendatory battery.
2. Research the electric appliance and the laptop battery contact elements is whether clean, when necessity is clean with the wet cloth mop, after dry loads according to the correct polar direction.
3.When non-adult custody, don’t let the child replace the battery, compact battery like AAA should place the place which the child cannot attain.
4.Don´t make new and old or different model battery put off.
5. Don´t try to make DELL 6000 battery rebirth use hot up, charge,or other way.
6. Don´t let battery short circuit.
7. Don´t hot up laptop battery or loss it in water.
8. Don´t strip battery.
9. Electro-adapter should cut switch after use.
10.Should take off DELL 6000 battery from adapter when battery long time no use .
11.Battery should stock in cool place,and dry.

 

[AeroFury]

Registered me only for this discussion.

I just got a brand new laptop and I've noticed even though my battery is fully charged (100%) and has been plugged in with the AC adapter for the last 3 days, the battery has depleted to 97%.
So you're stating that it's actually better to remove the battery and work on electricity when I'm at home for the weekend and I'm not going to use the battery instead of leaving it in the laptop and constantly charging it?

 

[Perris Calderon]

Registered me only for this discussion.

that's one of the reasons I started the discussion, welcome, I hope you stick around

I just got a brand new laptop and I've noticed even though my battery is fully charged (100%) and has been plugged in with the AC adapter for the last 3 days, the battery has depleted to 97%.
So you're stating that it's actually better to remove the battery and work on electricity when I'm at home for the weekend and I'm not going to use the battery instead of leaving it in the laptop and constantly charging it?

I'm saying that once the battery is depleted (to a point, say 20-40 percent) it's best not to charge the battery until you think you're going to need that charge, then once charged leave it plugged in.

the battery permanently depletes more with a full charge then with a partial charge so the longer you spend on full charge the faster the battery permanently depletes, the longer you spend on partial charge the less the battery permanently depletes

there are also a finite number of charge cycles a battery enjoys

don't worry about a full discharge as far as the laptop is concerned, it won't allow you to use the battery to the point of damage and will turn off before that's an issue

now there are those on this thread that believe my strategy is counter productive so please read the entire thread, including links before you decide

also, as has been suggested, you're riskling a loss of data if you kick out the plug by the wall or latop so insure those are secure cause I agree with that concern

 

[X-Istence]

Registered me only for this discussion.

I just got a brand new laptop and I've noticed even though my battery is fully charged (100%) and has been plugged in with the AC adapter for the last 3 days, the battery has depleted to 97%.
So you're stating that it's actually better to remove the battery and work on electricity when I'm at home for the weekend and I'm not going to use the battery instead of leaving it in the laptop and constantly charging it?

If you charge a battery to a 100%, then remove it from your Laptop and let it sit for 3 days the battery will slowly discharge because of the nature of Lithium Ion, the same thing happens when plugged in for 3 days. After the battery is done fully charging the charging circuit will shut off, and since your laptop has not been on battery power the battery will slowly discharge, it should charge again at around 95% or so. 3% is a tad much for just 3 days though from my experience but it all depends on the charging circuit built into the laptop, the type and quality of the batteries, and the circuit inside of the battery pack that keeps everything in check and its parasitic current draw.

 

[Mazzman]

Hi everyone,

I had to chuckle because I wanted to make my laptop battery last and run longer just like everyone here, but went about in a very different way. Is. After I did my research I was able to design a 6 cell pack would last about 2x as long (500 charging cycles vs typical 300 charging cycles) with increased energy densities....(5800 mAh /62.6 WH). The stock dell battery that came with my laptop was rated at 4840 mAh. My dell laptop went from a little over 2 hrs of run time to a solid 3 hrs without having to put my laptop into energy miser mode.

When I read the thread I though people following this thread might be interested in that product I plan to introduce on the market in 3-6 months. I'm also working on some other batteries that will offer performance improvements.

More details about the battery specs are on the site Im currently building ... MaxCapacity.Co.

Let me know if this is a product you guys/gals would be interest in. If you are great let me know. If you are not let me know that as well. All opinions and questions are welcome.

Thanks,
John

 

[Perris Calderon]

Hi everyone,

I had to chuckle because I wanted to make my laptop battery last and run longer just like everyone here, but went about in a very different way. Is. After I did my research I was able to design a 6 cell pack would last about 2x as long (500 charging cycles vs typical 300 charging cycles) with increased energy densities....(5800 mAh /62.6 WH). The stock dell battery that came with my laptop was rated at 4840 mAh. My dell laptop went from a little over 2 hrs of run time to a solid 3 hrs without having to put my laptop into energy miser mode.

When I read the thread I though people following this thread might be interested in that product I plan to introduce on the market in 3-6 months. I'm also working on some other batteries that will offer performance improvements.

More details about the battery specs are on the site Im currently building ... MaxCapacity.Co.

Let me know if this is a product you guys/gals would be interest in. If you are great let me know. If you are not let me know that as well. All opinions and questions are welcome.

Thanks,
John

interesting post, we don't usually allow first posts that promote personal products but in your case I think the post should stand, your product sounds like a winner to me, feel free to post links so long as you participate in the thread

good luck john

 

[osnntec]

Well I always used to leave my laptop on charge when I see baterry down with 20-30%.

 

[Mazzman]

interesting post, we don't usually allow first posts that promote personal products but in your case I think the post should stand, your product sounds like a winner to me, feel free to post links so long as you participate in the thread

good luck john

Thanks Perris will do.

 

[Mazzman]

My 2 cents on "how to get longest life" from your li-Ion battery.

Nice discussion thread and a lot of good info already covered. As stated before the loss of capacity in the battery occurs primarily on the charge. This is when then anode and cathode inside the battery get a material buildup on them which is what increases the resistance and leads to cumulative loss of capacity in Li-Ion and Li-Poly batteries.

I might also throw into this discussion the issue of heat. Meaning that possibly anodes/cathode build up more resistance on them per full charge when charging occurs as the temperatures move closer towards the operational extremes for the batteries. I will also state that I expect this behavior to vary greatly or even not exists based on the specific li-Ion formula being used and design of the anode and cathode. I should state that I dont have any manufactures datasheet that quantify this effect for their products. But I think I've seen this somewhere... I will check and update if/when I find the published numbers for a manufacture of a "standard" type li-ion battery.

I had spoken to one cell manufacture that touted the wide temperature range their cells had and the ability to maintain a full capacity across very high operating temperatures. The suggestion was that somewhere around 100F typical Li-Ion cells lost 30% of their capacity making cycles on batteries occur quicker with higher temps.

Granted this is probably more of an issue for electric cars, then someone using their laptop in a house/office with AC. But for those of you that have laptops that run hot, use them hot environments, or someone perhaps charging that black phone in that 140F car during the summer... perhaps this is a way to help keep you battery in good shape and extended the service life.

John

 

[Mazzman]

Here is an interesting concept that some EE's use when they need to have a li-ion battery last many years say 5 to 10 years.

If one could lower the charging voltage so that that battery only charge it to a max of %50 -%70 of full capacity, one could avoid much of the wear and tear that happens to a li-ion battery significantly extending the life by a factor of about 2 to 3 times. At %50 perhaps 6 times as long. (I believe is has to do with avoiding the extra heat that is created because its tougher to get the last %20-30 of power in as opposed to the first 70)

I was thinking about lowering the charging voltages of some of the batteries I have until I saw a new Lenovo that had software in it that would stop charging the battery and consider it full at around %80. Recharging once the battery is down to %60 or %70. Hummm ... the voltage is not lower but seems to do the same thing! Lenovo called this setting "Optimize for battery life" or something close to that.

I think a software solution to this seems to be much better solution than designing in a fixed lower voltage into the battery. I'f I need more run time then I just turn the feature off and charge to %100. Once I'm done I put it back.

So for those that don't have laptops with software that does this, one could manually take the laptop battery out around 70-80 percent to control this behavior. I know ... what a pain in the neck... but if you have the patience to do it you can extend the life of your battery.

The only way I think the results might not be duplicatable is if your laptop really runs hot and you battery pack is always saturated with heat.

Anyway congrats to Lenovo for figuring this one out!