take battery out while on ac power?

jw if anyone does this and if cause any harm to the camputer.
Im thinking I can extend the life of my battery instead of letting it sit on 100% for hours on end plugged in

 

I always take the battery out when on AC. Battery sits at around 70-75% in a cool place.

 

i do take my NB to trips but when im home it usuallt sits on the ac adapter for the next 24-48 hrs

 

I use the charge threshold at 36/40% and let my battery plug into the notebook for backup in case AC get pulled. It's been through about 75 cycles (100% down to ~20%) this way and still holds about 95% of its full charge with that routine.

 

How does your battery power ever get to ~20% if the charge threshold kicks in every time at 36/40% ?

 

I ruined a Dell battery just by not taking it out when on AC., so I read some tips on how to enhance battery life.

 

I meant that's what the cycles are for my notebook when it goes through them; 100 down to ~20. But other than that, I normally keep my battery charge while plugged in at 36-40%.

 

You start charging when below 36% and charge up to 40%? Is that what you are saying?

 

Okay. I think I know what you mean: Your battery power can go as low as ~20, but rarely does, since your laptop always begins charging when the threshold of 36/40% kicks in.

 

are you aware that most new notebooks clock down the CPU when you take out the battery while running on AC?

mine hardware downclocks to 1200mhz from 2000mhz, and i know many others' do too

i have a core 2 duo

 

Ok lol. Here's the deal;

I'm a college student, so I have to very mobile with my computer. But only on some days do I need to carry my laptop around from class to class without an outlet to plug into. So to work around this, I charge my battery to 100% the night before. By the end of the day, I end up with ~15-20% charge left. Each time I do this (about 4 days a week), it would add a charge cycle. Apparently I have done this 75 times.

On weekends and days off, I would keep the battery charged at around 40% and plugged into my computer.

So with this routine, I'm still able to withstand about 95% charge of the advertised battery life.

Sorry for the confusion.

 

so u dont allow your pc to charge ur battery more than 40% on weekends?

 

Correct, because I'm at home and I'm not taking it anyway, so I leave it plugged in.

 

does anyone know for sure if once the battery reaches 100% if the pc stops charging the battery and uses only ac power?

kinda off the wall question but worth a shot

 

I know it stops charging until the battery gets to 96 or 97%, then starts charging again.

 

?????
do you mean it stops charging after the battery gets to 96-97%?

 

I think what he means by this is that until the battery has actually dropped down below a certain percentage - 96% as is the default of Lenovo Power Manager - the computer will not charge it again to prevent loss of battery life.

So simply put:
Battery use goes down
100% - no charge to prevent loss
You must then use your notebook on battery power to decrease the percentage to at least 96% before the computer will start to charge again.

I have my power manager set to "optimize battery lifespan". Seems like a logical choice right, or should I be setting my own threshold?

 

That's exactly what I meant. I don't rely to much on that software and I only install my batt. only when I'm flashing my bios or working on something really important, so I don't mess something up.

Anyway, I'm still searching eBay for an extended battery. After I get it, maybe I'll stick this little 4 cell battery in.

 

Let me clear this up. The "fully charged" option is a 96/100 setting. What this means is that whenever the charge level is below 96%, it will charge to 100%. If the charge is between those numbers, it will not charge. Instead, it will just stay put.

People seem to forget that concept. If you see your battery charge being stuck at 97% or 98%, it is because it is not below 96% which would allow it to charge. If it's stuck and you want to see a 100% reading, then discharge the battery until it is below 96%, then plug it back in until it hits 100% without ever unplugging while it is in between 96% and 100%.

I hope that clears it up.

 

so now that we know that it stops charging above 96% , which brings us back to my original question.

I was worried that it would be bad to keep the battery on my PC for 24-48hrs while its sitting at 100%. which woudnt be bad at all cause it stops charging the battery then, right????

 

It will extend the life of the battery to be removed while you're on AC power. My last Thinkpad battery power diminished a lot faster than my current machine because of this. Just store it in a cool place and charge it up every couple of months, if most of the time your plugged in.

 

It's not bad per say...but it's not as good as storing it while the the charge is at a lower energy amount like 40%.

I suggest that you read the Battery Guide for more detail on battery maintenance.

 

I'm a new T61 owner. So far I haven't taken it anywhere that I've needed to run it only on battery. It's just sitting at my desk while I get used to a notebook instead of my desktop. So...I've got the battery management set at 60-80. In reality I could just take out the battery because I'm really not paranoid about the power going out. But after reading this and other threads about "battery in/battery out" I'm still not clear as to the best course of action.

1. I never unplug my desktop. Is unplugging a notebook without the battery in somehow different? Assuming I've powered down, of course.

2. I read about "battery cycles". Is that a number that's listed somewhere in the T61's battery management section or just where is it? And, are we talking about cycling from real low (like 10%) then all the way back to 100%? Or just going between my parameters of 60% to 80%. Is the number of "cycles" finite and does that finite number differ between what I'd call "full cycle" as opposed to just up and down my current +/- 20%?

3. There's more. If I know I'm not going to be taking my notebook away from AC power, I'm not paranoid about the power going out while I'm using it (it's never gone out while on my desktop, ever) and while I'm using my notebook I see the battery meter "cycling" from 60 to 80 back to 60 up to 80 etc etc (of course slowly, but it is happening) now my question is: am I just uselessly burning the finite number of cycles by keeping the battery in and constantly charging? Is the useful life of this battery going to be reasonably extended by taking it out and letting it sit while I'm plugged in or is it that no matter what I do with this battery it's useful life (in months or years) will be about the same (and the potential loss of data from a loss of AC power trumps whatever minor extension of its life might occur by taking it out when not-needed)?

4. My only other real-world experience with Li-Ion batteries is with my digital cameras and of course with them I wait till they're almost out of power then charge them up. There's no constant charging and they live as long as they're going to live. It's a totally different with a notebook's Li-Ion. OK, I'm done with my questions.

 

It could just be me, but ever since I installed the battery software, my computer hasn't ran as smoothly as before. Maybe it was SP1 but I removed that. I think I'm being paranoid and stupid. I guess computers get slower as you use them...

 

@spotburner
Spot on with the questions, those were exactly my questions too.

to quickly recap:
A lot of us use the notebook mostly on AC. Given that, whats the best way to ensure that our batteries last for the longest period of time?

the choices we have are:
1. charge battery to 100%, remove from notebook, store in cool place, and merrily use the notebook teh entire time on ac. Then Plug in battery once in a few months (2?) to discharge it completey and recharge.

2. charge battery to 40%, remove from notebook, store in cool place, and merrily use the notebook teh entire time on ac. Then Plug in battery once in a few months (2?) to discharge it completey and recharge.

3. Keep the battery in notebbok permanently, connect ac and keep charging/discharging the battery periodically with certain limits (60/80 etc..).
(if this option is true then somebody please tell us what the best figures are?)

4. keep battery permanently charged at 100%, AND keep the ac power connected.


again to summarise:
given that we have AC power avaliable 95% of the time, whats the best strategy for us to maximize our battery life. Personally i am not too concerned if my system runs marginally slower if its on AC, as long as the performance is not too bad (say 90% of the ideal). But it is critical that the battery lifetime lasts for as long as it possibly can.

whew, thats it i think
please, can the knowledgable people on this forum provide some guidance?


thinkpad t61
14.1 wide, core 2 duo 2ghz, 1 gb ram, win xp pro, 6 cell, integrated graphics.

 

What battery software are you talking about - the Power Manager thingie?

 

What I do is:
1. Let the battery stay in the laptop.
2. Using the AC while setting the battery to 15/40 cycle.

 

Yeah, the program that you can download from lenovo's site. It ends up having a battery icon at the bottom right. It's really useful, but I dont know if it's worth any decrease in performance. This shouldn't be, and again, could be something else or my imagination.

 

is this true?

 

how do you set charging cycles? is it a lenovo software? I currently have a HP and its battery failed within a year. It only gives me about 20 mins of use. I have it plugged it almost all the time since it originally it only gave me about 1 hr of use, not too long.

 

Setting charge tresholds is part of ThinkVantage's Power Manager, which is exclusive to Lenovo systems I believe.

Check out the Battery Guide for Battery Maintenance.

 

I was gonna ask questions about that. I have that problem. Gonna see if it's true..

 

I'd say it's plausible. I always read that it's best to use your notebook plugged in but I'm sure there is a setting to maintain that same power even on battery. Perhaps a BIOS setting?

 

I've tried setting the CPU speed to max in the BIOS for AC, but it still reverts to 1.2 GHz when the battery is out. And getting it to go back to 1.8GHz (my max) isn't as simple putting the battery back (I think I had to restart, hibernate isn't enough).

 

Why on earth would it throttle down if it's getting AC power (w/no battery)? If anything you'd think it would power down when running off of the battery alone, to save juice.

 

Has everybody turned off PowerMizer in the NVIDIA Control Panel?

 

Thanks, just another plus for getting a thinkpad.

 

I don't have it. (X3100)

 

It has been this way with all ThinkPad models for many years. It has been discussed on other forums. There is no setting to get around it. If you don't have a battery installed, you will not get full CPU speed. There's nothing you can do about it. The reason for it is to prevent the laptop from drawing current spikes larger than the AC adapter can supply, resulting in a voltage drop to the system causing crashes, data loss, etc. With a battery installed, it acts as a buffer to keep the supply voltage consistant...

 

Arkit3kt has the right idea. Lith Ion batteries like to be around 40%.

I have a T60 that gets about 40% of its advertised price ... I always left it plugged in.

I just wish Dell had an option for this - I use my Inspiron as a desktop and it always sits on AC Power behind a UPS.

 

where in power manager do I go to set charge parameters?? ILL probably do 30-50%

 

In Power Manager, go in the Battery Information tab, and click on Battery Maintenance. It's the charge thresholds.

 

Hello folks,
While we've got this battery thread running can I just ask a slightly varying question? My new T61p arrived yesterday and it's my first ever laptop. The 9-cell battery gets warm and also shakes/moves around a little in its locked position. Are both of these to be expected? Also, can I plug/unplug the battery and ac adapter while the machine is on or should this only be done when switched off?
Thanks to everyone for their comments already on this thread. I had no clue about these battery protocols and hopefully I'll now avoid any grave errors in that department.

 

Are you using a program to check te speed or are you just looking at the system information in the control panel?

 

The battery has a little play to it, but not much. And yes, the battery gets very slightly warm. Nothing to worry about though.

You can unplug the battery while it's on AC or you can unplug the AC while it's on battery. It's safe to do either as long as your notebook always has a power source.

 

I usually just check in System Properties, as it seems to detect the changes quite rapidly, and I have verified it with CPU-Z a few times and it was right every time.

 

I experienced the opposite effect. When running on AC (w/ or w/out the battery installed), my cpu speed reads 2495 mhz (from CPU-Z). When running on just the battery my cpu speed reads 1596 mhz! I'll stick w/ AC and no battery as much as possible.

 

What are you guys reading your CPU speeds from? The system information in Windows?

Because I just got my new R61 and as far as I can tell the CPU speed's not changing when the battery is out. I haven't had time to try another program though.

 

download CPU-Z......

http://www.afterdawn.com/software/desktop_software/other_tools/cpu-z.cfm

 

I just wanted to add that when I selected the "Maximum Performance" scheme, my cpu speed remained at 2495 mhz, just w/ the battery inserted.