Battery -- keep it in or out when on AC all day ?

[guYom]

For those of you using the T60 as a desktop, do you keep your battery in or out? If out, do you keep the battery fully charged? How often do you recharge it if you keep it out?

Thanks for your feedback (hope to get more answers...).


********

I have been reading up on batteries here on the board and in the help on the TP. Not sure what to do anymore...

I am using my laptop as a desktop, all day long 5 days a week, and I'd say about 80-90% of the time. I am mobile and use it as a lappy a few times a month, but not every day.

With my old laptop (same usage and kind of li-Ion smart battery) :

-- Battery was out after being charged fully

-- Before a trip or mobile use I would make sure the day before that the battery was fully charged

-- When on battery power, I always ran the laptop until no juice was left in the battery, then recharged it and took it out and left it on the shelf

So my battery was always kept fully charged when not in use, but out of the laptop, and always went through a full / complete dis-charge cycle when used.

After nrealy 5 years of use in that fashion I am still getting 1.5 hours from it (versus 2 hours when it was brand new), so it seems to have worked for me. I was under Win 2K.

In the help in my TP under XP Pro I read that I should keep the battery at 50% charged, never fully charge it, but keep it in the laptop at all times, so there is some kind of trickle charge happening.

What should I do? WHat do you do with your batteries those of you using your TP as desktop? Keep it in? Out? Tweak the settings?

Thanks for your input.

[snife]

Seems like a lot of work to me for the cost you can find T series batteries for after a while.

I would keep it in - you may not get full system performance without it, check out Power Manager (Start>ThinkVantage) which has threshold charging options which will stop your battery charging small increments and stop battery loss other than that of normal cycle count and age.

[Interpol]

Just keep the battery in. You never know when somebody's going to walk by and kick the power cord out of your laptop, or when there's a power outage.

[guYom]

one of the reason I was keeping the battery out was also because of the heat it generates while being charged, I thought this was better for the laptop as a whole. But I did not have any Power Manager as the one in ThinkVintage in my Samsung laptop.

Anyone using their TP as desktop replacement 5 days a week 8 hours a day? Do you really keep your battery in?

[christopher_wolf]

one of the reason I was keeping the battery out was also because of the heat it generates while being charged, I thought this was better for the laptop as a whole. But I did not have any Power Manager as the one in ThinkVintage in my Samsung laptop.

Anyone using their TP as desktop replacement 5 days a week 8 hours a day? Do you really keep your battery in?

Whenever my Thinkpad is on a desk functioning in the desktop replacement role, I just leave the battery in. I have done so with all my Thinkpads and have, thus far, not noticed any difference. I remembered taking the battery out, on a regular basis, when my system was plugged in for longer than a few days; I did that for about one month and it didn't help or hinder the wear level on the battery from what I could see.

[al7kz]

You never know when somebody's going to walk by and kick the power cord out of your laptop

Exactly, and if someone (or you yourself) does trip over the power cord, you'd be lucky if it does pull out. More likely, like what happened to me, is that the computer will go crashing to the floor. Fortunately the only damage to my 760XD was the hard drive coming loose from its mooring connector.

[NS]

Ok, i am the jerk who kicked and tripped over my own cord always. I will strongly suggest STRONGLY ... keep your battery in. You will never know when there will be power cut off from your computer through the AC outlet. The battery is for you to shut down your computer safely to prevent any further data loss and...

So keep your battery in.

NS recommends you to keep your battery in for your T60

[jagged]

I use my T60 as a desktop replacement and have it running for at least 12 hrs a day, 7 days a week. One thing I like with my Thinkpad is that there's no heat issue at all (can't same the same for all my other notebooks).

Anyway, yes, I also recommend to keep the battery in and use the Thinkvantage battery manager. What I did was set up the max charger to 95% so I don't accidentally overcharge. Some of my friends don't to conserve and make their battery last a little longer but I don't care.

Sure, after a few years, your battery might not perform like when its new but batteries are easily replaceable and I think losing data cuz someone trip the wire cord is a bigger hassle.

[christopher_wolf]

The battery is eventually going to lose its capacity after a while anyway, so it is best to use it the way you see fit; besides, it is a good backup if the AC line power is shut off for some reason in the middle of your work.

[mpcook]

I have been using my X31 as a desktop in port replicator for the most of the past 2.5 years. I leave it on 24/7. It travels from it's AC maybe once amonth and gets turned off maybe once a month as well. It is hot, but has been fine all along and no problems.

[guYom]

Thanks mpcook.

I turn off my laptop every night, but other than that I use it pretty much like you -- mybe I use it a bit more as a mobile 3 or 4 times a month.

When it is 'docked' in, do you leave your battery in? If so what settings do you use for recharging your battery (how low does it have to be to recharge)? Do you recharge it fully or only half way?

Getting caught up in the cord is not a reason for me to keep the battery in, nor is power outage which can also happen with a desktop. I just want to do what's best to generate less heat, keep the battery going, etc.

Thanks.

[Phantom Gremlin]

Anyway, yes, I also recommend to keep the battery in and use the Thinkvantage battery manager. What I did was set up the max charger to 95% so I don't accidentally overcharge. Some of my friends don't to conserve and make their battery last a little longer but I don't care.

I also use 95% as my max. In the same place you set the 95 you can also tell it not to start charging unless battery goes below some other number. I use 75% for that. You can choose whatever number you want.

Using the 75/95 scheme my battery is only charged once every few days. It's not charged just by sitting in my mini-dock. It discharges when I take it home at night after putting it into Stand By, but often times it won't start charging again next day because it didn't get below 75% overnight.

I learned about mobmeter.exe from this site. It will tell you if your battery is being charged or discharged.

[jdhurst]

I have adopted a "who cares" attitude. Li Ion batteries are a big leap forward from prior technologies, and I use AC or Battery as required and pay no attention to any other care. My T41 is now 30 months old and is on the original battery. It needs replacing (normal) but still goes for an hour and a half. ... JD Hurst

[mpcook]

I have been using my X31 as a desktop in port replicator for the most of the past 2.5 years. I leave it on 24/7. It travels from it's AC maybe once amonth and gets turned off maybe once a month as well. It is hot, but has been fine all along and no problems.

I have never removed the battery. It seems to be faring well.

[guYom]

I have set the battery management option for

recharge when below 75%
charge stops at 95%

I have let my battery charge fully, the battery gage in the tool bar says the battery is charged at 100%. Is that right? Or is it really at 95% only as the setting indicates? When I was charging the battery the computer was not running (it was turned off) if that makes a difference.

Thank you in advance for enlightning me on this charge stops at 95% and what it really means.

[NS]

I have set the battery management option for

recharge when below 75%
charge stops at 95%

I have let my battery charge fully, the battery gage in the tool bar says the battery is charged at 100%. Is that right? Or is it really at 95% only as the setting indicates? When I was charging the battery the computer was not running (it was turned off) if that makes a difference.

Thank you in advance for enlightning me on this charge stops at 95% and what it really means.

If the indicator shows you 100%, then it is 100%. But sometimes, the gaugebar might be inaccurate.

CAn you charge the battery when the computer is turned off??? I don't think i can charge when the computer is turned off. You need the CPU to tell the computer to charge up the battery, right?

* I am not sure*

[rvacha]

CAn you charge the battery when the computer is turned off??? I don't think i can charge when the computer is turned off. You need the CPU to tell the computer to charge up the battery, right?

* I am not sure*

No modern notebook is ever "off". When it is in the off state the majority of the machine (GPU, CPU, memory, HDD, interfaces, etc) has no power but the EC is always powered. It is the EC that controls battery charging and the switchover from AC adapter power to battery power. In most systems the EC is also responsible for waking up the system when the power button (and in the case of Lenovo machines the Fn key as well) is pressed. The T60 defintely can charge both batteries when "off".

[rvacha]

Lithium batteries such as those used in all modern notebooks can be severely damaged if left charging for long periods of time. For this reason the charger has a timer that is started when the battery is mostly charged - a state called float charging. After a predetermined length of time (typically in the range of 20 minutes or so) the charger terminates float charging and charging stops altogether. There is typically another timer called a fail safe timer that starts the moment charging starts. After a predetermined length of time (typically 3.5 hours) the charging cycle stops regardless if the battery is fully charged or not. The failsafe timer works independently of the float timer in most applications. The idea here is that if the battery hasn't fully charged by then, there's something likely wrong with either the battery or the charging electronics.

The bottom line is that leaving your battery in is effectively the same as taking it out. In both scenarios the battery isn't charging most of the time. Leaving it in gives you a freebie UPS, in fact I lost power this morning and the T60 didn't miss a step and I didn't lose any data.

[archer6]

I have adopted a "who cares" attitude

Brilliant! Thanks, you just put me in the right frame of mind. You have made a good point about the technology and I agree, one less thing to occupy my mind....it's corroded enough....

[guYom]

Thanks rvacha, this is most informative.

So in conclusion do you agree rvacha that for desktop use the optimum settings are start charging when below 75% and stops charging at 95% ? Thanks for confirming or for indicating a better setup for my kind of use.

One thing still puzzles though, it still says 100% charged although I am set at 95% (stop charging at 95%).

Do I need to reset the battery gage? Typically how often do you need to reset the battery gage? Is that a mater of many complete charge/dis-charge cycle the battery goes through?

Thanks again.

[raptor]

Another reason why battery should stay in.

http://forum.thinkpads.com/viewtopic.ph ... 607#177607

Regards
Raptor

[rvacha]

Thanks rvacha, this is most informative.

So in conclusion do you agree rvacha that for desktop use the optimum settings are start charging when below 75% and stops charging at 95% ? Thanks for confirming or for indicating a better setup for my kind of use.

One thing still puzzles though, it still says 100% charged although I am set at 95% (stop charging at 95%).

Do I need to reset the battery gage? Typically how often do you need to reset the battery gage? Is that a mater of many complete charge/dis-charge cycle the battery goes through?

Thanks again.

There is no "best" answer, it depends on how you use the machine. That's why Lenovo has added more smarts to the charger and allows you to change the thresholds. It also can watch your usage habits and make changes based on how it sees you use the machine. The three biggest things that reduce capacity and life (they are strongly related):
1. Temperature, specially hot
2. Fully charging the battery
3. The number of charge cycles

Temperature is easy - just don't leave the battery in a car or in the sun for prolonged periods and you are good to go here. Fully charging a current technology lithium battery requires charging it to 4.2V per cell. Many high availability/high reliability applications such as servers and implantable medical devices charge the cells to just 4.1V or 4.05V per cell. (The period where the battery charges from roughly 4.1V to 4.2V is the "float charge" period I mentioned above). reducing the voltage can increase life by 2x-10x. Of course the tradeoff here is that there is less charge in the battery and your machine will not operate as long on a charge. Picking wide thresholds such as 75% charge start, 95% charge end helps by reducing the number of times the battery actually goes through a charge cycle and this improves life significantly. The tradeoff here is that since it will not charge until there is less than 75% capacity left, you may grab the machine, unplug it, and find that there is only 76% charge on the battery - and therfore experience limited run time

If you are the type to grab your machine, use it for half an hour at a meeting and then plug it back in, this wide range will work great for you. Personally, I grab mine and travel for days, almost always running it down below 20% before I can recharge. If mine started with only 76% in the battery, I'd be sunk. The beauty of the Power Manager is that if you set it for "Optimize for battery lifespan" it learns how you use the machine, including how often you plug it in, how much capacity you use, etc. It will set the thresholds for you.

I have not played with the thresholds a lot, but it is possible that when the T60 reports "100%" it actually means it is fully charged up to the threshold you specified (i.e. 95% capacity)

Note that this smart learning mode is not available in T40 and T42 machines and *I think* was introduced starting with the X41.

Another neat feature is the battery reconditioning utility. This exists on the X41 but may or may not exist on the T60. This can help extend life a little but in my experience it does more to recalibrate the gas gage than anything

[archer6]

Temperature is easy - just don't leave the battery in a car or in the sun for prolonged periods

This is the challenge I face, as much of my travel is by car in Central California where our summer days are 103-108 every day. I put it in the trunk, as opposed to inside the car and cannot always bring it in with me. Any suggestions or ideas as to the impact?

Thanks....

[rvacha]

This is the challenge I face, as much of my travel is by car in Central California where our summer days are 103-108 every day. I put it in the trunk, as opposed to inside the car and cannot always bring it in with me. Any suggestions or ideas as to the impact?

Thanks....

Yes, I think its time to put your notebook on ice too! If the battery is kept at 60C for a year (just sitting there doing nothing) it will lose more than 25% of its storage capacity in one year. So you may be losing 50-100 charge cycles tooling up and down Rt. 99. Ah, but the weather's great there!

[archer6]

So you may be losing 50-100 charge cycles tooling up and down Rt. 99. Ah, but the weather's great there!

Thanks... I guess everthing has it's price...