Leaving laptop charger in at 100% for Asus Zenbook - Effect on battery?

Hi there,

Sorry if this is the wrong forum area, but I didn't see any of these questions in the "Asus" forum area so I decided to post it here.

I have an Asus Zenbook Ux31E and it's a great laptop so far, and of course, it destroyed my wallet, lol.

I just have a lot of questions about the battery life. The battery life is a bit weird, because at 100% charged, it drops to from 6 hrs 30 mins to 5 hrs 42 mins really quick and then lower and lower to 5 hrs and 10 mins, and then sometimes, it randomly goes to 5 hrs and 44 minutes. Is this battery time even accurate because it seems to drop fast then increase out of nowhere?

Also, what is the effect of leaving the laptop charger in while charging at 100%? I read many websites and people are a bit indecisive on the issue like some people say it's good and some people say it's bad. A lot of people say that these batteries stop charging themselves at 100% so it's safe, but then other people say that even though that's the case, they feel like it's not true and had times where the battery degraded from leaving the charger in, etc.

I used to have an HP laptop where I pulled the battery out and used AC power almost 95% of the time, and the battery life after 2.5 years, still is around 3 hours (which was how long it says it lasts initially). With this Asus Zenbook, you can't really take the battery out so I have no choice. I can either keep pulling the laptop charger out and keep recharging, or leave it plugged in.

I do a lot of stuff that drains battery easily too, like having Adobe PS, AI an ID all at the same time, sometimes play games and watch movies.

So what should I do in this case and what about the battery's condition? It it okay to leave it plugged in or do I have to pull the charger out every time it reaches 100%?

Thank you and I'm so sorry for the long post! I tried to give as much details as possible.

 

Windows' battery life indicator is not accurate, don't go by that. If you want to measure battery life, time it yourself; mark down the time you unplug the laptop and when you plug it back in. Then calculate.

Regarding leaving the notebook plugged in - laptops typically don't charge if the battery is at 90-95%. There's no harm leaving your laptop plugged in all the time. Just use it as you normally would.

 

As long as it doesn't make the battery burning to the touch dont worry. People here go nuts about how "easy" it is to destroy a battery by all sorts of stuff. If you don't plan on taking it off AC for a whole month then sure pull it out otherwise its not an issue...just use it.

As for your last statement never pull the charger out after it hits a hundred %. it is wasteful on wear. It is safer to keep it just the charger. I have meet many ignorant people that some how thing you can overcharge a battery....you simple can't because of a little thing called PCM/PCB....wikipedia it if your curious on how it works. Remember your time is more important than saving 3-6 months of juice over 3 years.....especially when your wasting so much time and patience over nothing.

Batteries are fairly cheap if you go on Ebay to buy them 3 years after a product comes out

i have found windows battery better than battery bar in multiply occasions

 

Thank you so much for the replies!

I just wanted a good opinion on this since this laptop's battery is pretty good. I hope the batteries are less expensive in some years then I won't rely on Windows telling me about the battery life either as suggested. It didn't seem right because it was dropping and increasing, then increasing. Was so weird.

Perhaps there are times where we can rely on it, but I guess not entirely? In any case, as long as the battery bar isn't at critical, then I'm sure it's still workable. I just wanted to time and see how long the battery lasts.

 

Problem is not the overcharging, properly built battery charger won't have such issues anyway. The real issue is that the battery will be at full capacity all the time with the AC plugged in. With LiPo(Lithium Polymer) chemistry, it likes it being at 40-50% when in storage.

Here it shows you that storing it at 40% capacity is better than at 100%: How to Store Batteries – Battery University

It shows that with 40% capacity, storing it at 25C temperature(77F) loses only 4% capacity after a year. With 100% charge, it loses 20% at the same 1 year timespan.

You don't want to use too much of the capacity either. When the battery drops below a certain %, you can damage it. 20% is a good limit.

I think the best is just to use it all the time, not going below 20%. Batteries, especially LiPo ones, are designed to be used. Leaving it at one charge state isn't a good idea.

 

Not this again... Battery University... a marketing tool to sell more batteries.

Call it a University and everyone will take it as gospel. It has been shown time and time again by NBR members, that batteries left in a laptop plugged in most of the time has little effect on battery life, well other than the normal degradation, maybe 5% a year. It is definitely a good idea to use it on battery on occasion, and even calibrate it every few months, or a couple times a year. But it will not lose 20% at 1 year, that is only for storage, if unused and untouched for a year.

I used to use BatteryBar, but started using BatteryCare, although I find HWInfo64 a lot more realistic for real time monitoring, although not very convenient.

 

I have a Toshiba Satellite that has been plugged in, and on most of the time too, for close to three years now save for the few times I've been out of town with it. Never had an issue with the battery life when I do use it that way.

 

That's because you take care of your battery more--even if you are unaware of it. Keep in mind that the conditions and/or environment also play a big part in how long your battery will last.

One person might keep their laptop on a highly heat reflective surface, while the other may always use a cooler. Heat is the enemy of your battery as well as your computer.

 

I may remember uncorrectly, but doesn`t all modern notebooks (I know cell phones does) have a safety feature that "shut down" the power draw from the power adapter once the battery is at 100% and when it is down to 95% the battery starts drawing power again from the power adapter?

Anyhow, what kills batteries are fully discharges since batteries have a certain amount of discharges it can do before saying goodbye.

 

Heat is the enemy of all electronics. My poor HP suffered because I screwed up and accidently blocked it's fan vents and it was never the same since then.

 

If you've ever wondered what you're paying for when you notice one battery is much more expensive than another. That being the safety devices--among other things--which activate to help prevent something like that from happening.

There is a wide gamut of quality in the battery world, and no real way to check other than through brand reputation.

 

Again, batteries have 300 full discharges and recharges before it hits 80% PERIOD You don't damage it when drained to 0% You damage it by draining below 0% but you can't because of the special PCB/PCM PERIOD Only way to bring it that low is to drain to 0% and leave it at zero for at least a weeks if not longer. Also trying to turn the laptop back on many any times will damage the cell. once or twice will not hurt but many many times will PERIOD

It is never good to cycle a battery non stop like a cell phone. It is better to just leave it plugged in PERIOD Your causing constant wear that way. This is why modern day cell phone batteries don't last more than a year because you can easily do 300-600 cycles in a 365 day period. I try to leave my EVO3D in but it is not practical 90% of the time because I am moving. I recharge my cell phone 2-3 times a day because i use it constantly so one battery will be dead within a year easy. Hence, why I have 3 batteries for my cell phone.

EDIT: Also read their charts 100% discharge gets you 500 cycles while 50% discharge gets you 1500, which is 750 after you factor in the difference so you get 50% more capacity before failure. The 25% discharge gets you only 25% extra capacity. The 10% discharge actually gets you a reduced capacity. Realistically, getting 25-50% more capacity is pointless when you actually count your time and money into the equation....unless you have a full blow house backup that has 10 grand of cells it really isn't worth the hassle. Note, they don't give you the exact rate of failure so these numbers are not completely accurate. We are assuming they hold complete capacity the whole time but that isn't true. They consider 40% capacity is end of life, which is very generous. I would say 50-60% capcity is end of life for me because you end up wasting so much electricity charging them to full power and waste so much time. Note, I am not positive on this one but I think when it has 40% capacity you still use the same amount to charge it or something like that....I think. I have not read up on that but I am guessing so if you read something documenting how that works please PM me because I would love to know. I think battery university has something on that. Also HTWingNut unless you have other empirical evidence to say otherwise I refuse to believe you. If you got the money and time please do it. I would love to see it. You could also send me the supplies and pay me labor and I would be glade to run all the tests for you. I work cheap

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

Until you do empirical research with a smart charger....not a freakin laptop don't give that mumbo jumbo. To properly tell how much a cell has you need a smart charger, which can tell you how much juice you have put in (Wh or mah*V, which equals Whs) and can discharge at a constant rate and tell you how many mah you have used (same formula as above). Than minus the two and you get actual capacity! So if you want to do an empirical study go ahead and do it but don't do a joke of a study with laptops...do it right. After you have used 10 laptop batteries or more in an empirical study like like I have stated above don't claim anything because you have no basis to warrant it. So please go buy a smart charger and test it and come back to me in a year because I would love to hear your results. Remember, document everything because I would love to see it. Until than, you have no basis to warrant such claims.

Also its not just modern laptops and cell phones. All Li-ion battery packs come with a PCM/PCB to prevent this. Granted I may be mistaken on the cell phones but I am nearly positive that cell phone batteries have a PCM/PCB....never taken one apart to see....hold on I'll take apart a razor Li-polymer battery right now to check. It does...or at least it looks like a PCM/PCB granted I am no expert. Alright, they are uploaded below and you can see it clearly

EDIT: Also PCM/PCB is not to just keep it from causing damage to the cell it is also there to keep it from melting/starting on fire/exploding...granted only certain types of li-ion cells will do that but all li-ion cells used in modern devices do use the type that will start on fire/explode if over charged. I think LiFePO4 cells are the only ones that don't cause a safety risk with out a PCM/PCB but don't quote because i am too lazy to look it up after doing all of this. Though they still need a PCM/PCB to keep them from charging too high/too low to maintain good battery life.

Sorta.....granted for my EVO3D I noticed the manufacture battery is better than the expansysUSA battery but not by a great deal. Manufacture batteries for a cell phone don't warrant a $40 price tag when it costs anywhere from $8-10 to make. I got the expansysUSA batteries for like 13 bucks Granted, they were a tight fit. I think they used lower capacity Li-polymer cells, which made it bigger and a tighter fit. I had to scrape off some plastic of the holder to make them fit easier. They are still hard to fit in the external charger but hey I am not paying $40 bucks for a 10 dollar battery

 

All the bargains in the world are worthless if your laptop explodes. Good luck trying to find the manufacturer who wants to own up to that name. Just be advised that no-name batteries are a crap shoot at best.

 

with laptops i'll buy the cells myself and replace them because it isn't that hard from what I have seen. Cell phones you can't replace on your own because you have to almost always get a custom built cell and at that point its pointless unless you want to buy a ton of them. Plus if you get a custom built cell you have to get it UN approved I think, which can costs thousands of dollars.

 

You can continue to quote sites that are pure marketing material, as well as theoretical results based off 2002 testing. Or you can use realistic results from users in the field which is the most reliable information you can get. Why would I use a smart charger when the laptop IS the smart charger? And how did you come up with 10 laptop batteries? Is that based off a six sigma strategy or just something you came up with? And you have no basis to warrant such claims because you have no clue how the results were obtained from the same site you keep quoting, other than taking it as gospel. Unless you work for Cadex in which case you're seriously violating forum rules by linking to a site that you work for.

Not to mention, as stated time and again, that's BATTERY STORAGE, not BATTERY USAGE. HUGE difference.

 

Sorry guys, I'm clueless about what's going on now and what everyone is talking about. I just wanted to see what the majority of people say.

 

i quoted information about battery wear with use as well. It is based off empirical evidence and based off countless manufactures. The fact that you fail to even recognize it or show anything makes you look ignorant. Also a laptop is not a smart charger. They are inherently in accurate and I can post pictures on why you can not go off of it. One of my laptops says it has ~950,000Whs....yeah accurate. Also my laptop wear bounces all the time. The only way to calculate it accurately is to use a charger that can give you read outs that are based off of use and charge. (The exact juice put in and exact juice put out) Not some BS internal OS/3rd party program that attempts to calculate it. I have proven that all those programs are inaccurate and at times windows battery even beats them.

Lastly, reread that site and my link they tell you how they tested for those. Again, it is like doing a study of a cars gas mileage on a varying path and relying on the full and empty signs...that is not a controlled test and is inherently inaccurate. An empirical study uses constants and does not deviate from them. It would be like putting 5 gallons of gas into a car and driving the exact same track each time and running it til it runs dry every time. Also, I said at least 10 batteries because you need a large test group to make sure your results are accurate. If you test one battery you don't know if its a bad one or a good one or average. You need a large test group to make results that can show patterns, averages, and highs and lows. If you look at their charts you can see how 5 batteries can have varying capacity. Also you would want to run the tests on a couple types of batteries at least 3 different manufactures so you can get a wide basis. That is at least 30 batteries from 3 sources. This would give you extremely accurate data. Again, refer to my analogy because your test is extremely flawed. Unless you want to prove that the programs have to be taken with a grain of salt and to show how to make a non empirical test.

http://en.wikipedia.org/wiki/Empirical_research Just in case if you wanted to read up on it. Any other, keyword is controlled.

 

It's amusing that you cite a source for accuracy, then say it's not based on empirical evidence. I've yet to see proof of anything in a link provided in this thread or by non-anecdotal evidence. So little information about BattU's batteries and methods is provided that the information is far from citeable research. I've got no idea what you've proven by your experience.

As far as the OP's question goes, this thread has gone horribly OT. I always suggest just leaving laptop batteries and chargers in unless it's a workstation that is perpetually plugged into a UPS, if only for system stability. I live in a blackout-prone area, so a fully charged battery is always a good idea. Constant cycling will certainly cause wear, regardless of by how much. But really, what good is your 3-hour HP battery now 2 1/2 years down the line? It's not worth much in resale anymore and probably just caused you aggravation. In your sealed system, constant top-off/trickle charging will probably cause the least wear, if only because batteries seem to get hotter as further depths are charged.

As noted earlier, the most reliable indicator of wear is going to be your wristwatch. However, take even that with a grain of salt - after a year of use, your discharge rate will probably be higher than when factory fresh because the screen tends to fade so you set the brightness higher, you have more running in the background so more CPU is getting utilized, and the laptop will run hotter because it's gotten dustier.

Overcharging should not be a concern. If batteries overcharged, you would hear about many more leaks and explosions. Reduced capacity will not cause you to use more power, as was confusingly conflated earlier in the thread - reduced capacity simply means less of a charge can be held. It has nothing to do with the efficiency of your charger.

 

I have seen people that are totally NUTS about pulling a battery out.. Then when i ask them what the most well built laptops one the market are.. (They always say Apple Macbook Air..) i tell them that you CANT remove the battery in it.. so..

 

That's it. People stress out about it and preaching 20% loss at a year if you leave it plugged in as gospel is not helping. I honestly don't care what people do, but this is one thing that you just leave it alone and don't worry about it. To replace a battery in 2-3 years will most likely cost < $60 for most laptops. It's a small incremental cost of ownership of a laptop.

What I find odd is that people that ALWAYS leave their laptop plugged in get stressed about it, yet they never use it on battery, so WHO CARES? It's a built-in UPS then, and whether it gets 2 hours or 1.5 hours, most will use it for 10 minutes on a rare occasion.

 

...this is what i have been saying since day one. I leave my computer plugged in 95% of the time and it still has battery life. It is not worth the hassle because for a trivial amount of money saving.

EDIT: to who ever said about empirical evidence...some things they post they tell you how they tested for it and others they don't tell you how they tested for it. You honestly didn't read my posts......or at least very well. True they don't have a video recording of them running tests but none of their tests are out of place in numbers. Again, until you run your own tests and prove otherwise I refuse to listen to you because you have NO GROUNDS. Feel free and spend thousands of dollars to prove them wrong...I would love to see that but until then you are just running your mouth and wasting people's time. Hell send me the equipment and I'll do it myself if you believe that they are wrong. I'll donate my time to do it if your too lazy.

 

Leaving laptop charger in at 100% on ANY laptop it harming battery !!
It's totally wrong when battery is plugged in and it's full and users keeping it still connected u destroying battery !
If you not using battery always take it out or turn it off .
Same as with phone battery .. people leaving charger in phone even when is full and that is bad .
When battery is full and it's in when u turn on laptop it will charge laptop again once it reach 100% charging will stop but battery is of course discharging slightly so when is connected charging doing : start stop start stop start stop loop and destroying battery !

 

Do not store your laptop with a full battery charge for long periods. You should not store it with a fully drained battery either. In learning how to care for your MacBook battery, you should store your laptop with around 50% on the battery. A fully charged battery can lose battery capacity with long storage. A drained battery can lose its ability to hold any charge with long storage. Fifty percent is the right balance between.

 

Little to no effect - there is a reason why smart batteries are used nowadays.

 

Number one - What you just said applies to research done on Lithium-Ion Batteries.

Number two - What the Asus Zenbook uses is a Lithium Polymer Smart Battery.

Number three - What a Smart Battery does is to stop charging at 95% and above through a internal logic board. Windows is fooled into saying that battery is still at 100%.

Number four - What is measured to cause degradation of batteries are battery cycles. It takes about 20 to 50 slight discharge and charge of 5% to use up 1 charge cycle. Batteries nowadays have between 300 to 1500 charge cycles.

Number five - Battery University published that related articles around 2004.

Number six - Old information is old.

Number seven - Never ever call others stupid. Keep it friendly. You may look like a fool otherwise.

 

Thank you yknyong1... +1

Solid logic and factual. Don't know why some people get so apprehensive about it.

And regardless if Li-Po or Li-Ion ... it is ok to leave your battery plugged in.

 

People who really *need* the battery capacity, have nothing to worry about. They never leave their laptop plugged in every day anyways

 

Saying that it' is "ok" to leave your battery plugged in is a little bit misleading, and I suspect may be the impetus of why some people get so emotional about it.

To be factual, it does cause harm to the battery. However, just as sun exposer is harmful to the skin (yes, a tan is the result of skin damage) it may be negligible compared to the battery wear over the long haul.

 

Well that's the point, but saying GOMG your battery will be dead after a year if you leave it plugged in is chicken little.

 

Sorry, but it seems you're like a lot of people in other online discussions who fail to read that the fact that there are Ultrabooks and Macbooks out there where you can't remove the battery by pulling a switch and letting it fall out. If it were that easy, I wouldn't be asking, honestly.

 

Which is something you have to admire about Apple: They make the decision for you.

 

I don't get it..

 

No worries

 

There is little to no effect on the battery because the battery used in the ASUS Zenbook is of the new Lithium-Polymer type.

Hope this clarifies.

 

Thank you for the wonderful clarification!

I actually meant I didn't get this:

But it's okay. Thanks again

 

Yes sir; Same with iPhones.. or This 5yo Blackberry in my pocket.. Battery will run for 4 days straight still..