Really long 1% battery life...tum tum tum

[lvlolvlo]

I wanted to completley drain my old 6 cell battery, so I popped it in and Battery MaxiMiser read it at 1% so I fig'd a few minutes and it'll go bye bye (as saftey I set my notebook to hibernate with battery reaches 0%). However, to my surprise as I sit hear seriously 45 minutes later, it's still going!!! Yes the orange light is blinking. I'm thinking it's not reading right, so once this battery is fully drained I will recharge it and post an update to my findings.

Currently Battery MaxiMiser is reading Full Charge Capacity 26.31 and a Design Capcity of 47.52...we'll see after it totally discharges and recharges what happends.... tum tum tum...

[jsmit86]

Currently Battery MaxiMiser is reading Full Charge Capacity 26.31 and a Design Capcity of 47.52...we'll see after it totally discharges and recharges what happends.... tum tum tum...

Draining it to 0% is a good way to ruin a Li-Ion battery! This may be why your Full Charge is only 26.31. I'd suggest getting a new battery, and charging it when the system warns you at about 10% or so. These full discharges are bad news!

[lvlolvlo]

Well here's the thing, this is my old 6 cell that went bad some time ago (June) so I wanted to just see the effects.

In any case, the final vderdict is in, in this isolated case. After completley discharging the battery jsmit86's statement holds true. It not only ruins, but destroys battery life. The Full Charge Capacity went from 26.31, as stated earlier, to 26.28. Yes this may seem small, however subtract the two to yield .03, multiply it by the cycle count(235) I have in the Battery Information Status Detail tab and you get 7.05. Add that to the Full Charge Capacity, and you get something closer to your Design Capacity.

Conclusion, don't do it. Listen to the people on the forums and don't do a full discharge. My tests results kinda confirm this.

Hope this was a bit helpful to some.

[jsmit86]

Glad to know that this was only a test!

[Guest]

what about when you first get your computer? Can't i run it down to test the battery life.

[jsmit86]

what about when you first get your computer? Can't i run it down to test the battery life.

Don't run it down to Zero!

The "normal" settings warn you at 10%.
This gives enough time to safely shut down.

I had my first battery go down to 0% after my system hung during a suspend while closing the lid. I did not catch it, and lost about 20% of my battey life.

I also had the loose battery problem, so IBM sent a new one.

So far, it can get about 5 hours of wireless surfing.
My design Cap is 47.5WH
and my Full Charge Cap is 48.16WH with 23 cycles on the battery.

[epigram]

i don't understand why discharging it completely is bad for the battery.
the ultrabay slim battery always discharges to zero before it switches over to the main battery. so does this mean the ultrabay slim battery is on its way to premature ruin?

[Dirky]

Loose battery? Mine is a little loose, how do I know if it is too loose?

Mike

[MichaelMeier]

..

[Humpa]

i don't understand why discharging it completely is bad for the battery.
the ultrabay slim battery always discharges to zero before it switches over to the main battery. so does this mean the ultrabay slim battery is on its way to premature ruin?

A lot of people will point you to www.batteryuniversity.com/parttwo-34.htm ... which seems like good info to follow.
I had posted the following on another thread. It seems like good info to me, so I am posting it here also.

IBM has seemingly conflicting information on battery health/conditioning related to the Li-ion.
IBM has these 3 documents, the first 2 have some contradiction to reliable sources I've read on Li-ion health, but the third is correct:
1. http://www-307.ibm.com/pc/support/site. ... MIGR-50944

Extending battery life - ThinkPad A Series, G Series, R Series, T Series, X Series
Extending the battery life
The Lithium Ion battery pack for the these systems is an intelligent battery. It contains a microprocessor to monitor its capacity. Information of remaining battery capacity is passed to the system from the battery pack, and the system indicates the capacity in 1% steps from 0% to 100% with high accuracy. If the indicator appears to be incorrect, it is recommended that you cycle the battery (fully charge, then fully discharge) three times. This may occur when the battery is over charged or discharged.

2. And, if you click on the Battery Tips link on the Battery Health screen (click on Battery Information > Battery Health), you will see this:

Reconditioning The Battery
Reconditioning your battery can increase the full charge capacity of your battery. It is recommended that you let the battery run to less than 3% at least once a month.

Occasionally, it may be necessary to "deep cycle" your battery one to three times to give it optimum performance. This will require you to let your battery run completely down, and then to recharge it fully. It is recommended that you charge your ThinkPad overnight for a full charge from a deep recharge condition without leaving your ThinkPad powered on. A brand new battery should be fully charged overnight before its first use.

3. But, they also have this (which is the correct info, from what I've read).
This is the one place where ibm got it right. IBM specifically says: Do not deep-discharge Lithium Ion batteries
http://www-1.ibm.com/support/docview.ws ... us&lang=en

Getting the most out of your battery - ThinkPad General
Note:
Do not deep-discharge Lithium Ion batteries. Batteries can degrade when they are left unused for long periods of time. For some rechargeable batteries (particularly Lithium Ion batteries), leaving a battery unused in a discharged state could increase the risk of a battery short circuit, which could shorten the life of the battery and can also pose a safety hazard. Do not let rechargeable Lithium-Ion batteries completely discharge or store these batteries in a discharged state.

batteryuniversity has this page: http://www.batteryuniversity.com/parttwo-34.htm
.. which is summed up at the end, by this:

Simple Guidelines

* Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.)
Short battery life in a laptop is mainly caused by heat rather than charge/discharge patterns.
* Although memory-free, apply a deliberate full discharge once every 30 charges to calibrate batteries with fuel gauge. Running down the battery in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate. The battery life will not be affected.
* Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.
* Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)
* Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing date. Do not buy old stock, even if sold at clearance prices.

It seems clear that Li-ion battery health is adversly affected by deep-discharges. If you try it, you will see (just check your full-charge capacity before and after).

[Dirky]

Much excellent battery information.

But what about my loose battery?

If I tell them it is loose, are they likely to send out an advance replacement?

thanks
Mike

[Humpa]

If I tell them it is loose, are they likely to send out an advance replacement?

The way I understand it, is that IBM will send you out a new battery. They will also send you the return label/package/whatever. After you return your current battery, they will check it out. If they deem that there is nothing wrong with the battery you returned, they will charge you for the battery they sent you. This is what I was told, at least.
A lot of people have done it, though, and have not had to pay. So, just make sure you tell them how unsatisfactorily loose it is. If you move it enough, can you get it to break electrical contact? That would certainly be reason enough.

I have the Sanyo, but it barely moves in my 15" T42.

[Spectra]

The way I understand it, is that IBM will send you out a new battery. They will also send you the return label/package/whatever. After you return your current battery, they will check it out. If they deem that there is nothing wrong with the battery you returned, they will charge you for the battery they sent you. This is what I was told, at least.

Don't worry about it. IBM scraps all batteries as soon as the return boxes are opened up.

[thenew3]

Just got 5 T42's and noticed the 6 cell is designed for 47+ WH but only holds around 44 WH on a full charge. Everytime I discharge the battery (not down to 0%, typically down to 50% or so) and recharge it, the full charge capacity goes down a little.

This seems to be a really poorly designed battery.

My 3 year old compaq evo n600c has the original 6 cell battery, design capacity 57wh, full charge when new was 65 wh, after 3 years of use it is still at 62wh. and it gets discharged to 0% (recondition) once a month. It's got over 1000 cycles on it, and still holds its original charge (this is on 5 batteries, so it's not just a single sample). still lasts 4.5 to 5 hours on the machine doing wireless surfing.

I'm lucky if I get 3 hours out of my T42's battery. I was hoping to get atleast 4 to 5 hours considering "centrino" is suppose to be less power hungry then the P3 in the compaq.

do all IBM batteries lose their capacity so quickly? or do I have 5 duds?

[CyberDude]

I have a Sanyo battery.

Design capacity: 47.52Wh
Full charge capacity: 37.69Wh
Charge cycles: 115

I only get around 3.5 hours out of a charge now. When travelling and working on the plane sometimes my battery drops to 3% so I guess that's been stuffing my battery.

Shame IBM don't make it more clear about the effects of letting a Li battery run down.

[DrMarco]

Not so long ago, I also wanted to drain my battery and I let it go to 0% (I am not sure whether this can hurt the battery that much if done once in a while).

I also observed that I could go on for 25 more minutes with the gauge at 0.2% . I do not remember exactly but I believe that this was with a 9-cell battery with full/design capacities of 65/71.

Now a simple remark: all we can say is that the time it takes for the gauge to reach 0 from full charge decreases slowly.

If the computer can continue that long after raching zero, the gauge cannot be trusted. If the gauge cannot be trusted, then perhaps the full charge capacity indicated is bogus and is probably underestimated. In this case, we should probably not worry about it decreasing slowly.

I remember I had estimated that the extra 25 minutes more or less corresponded to the loss in full charge capacity from 71 to 65.

[Humpa]

My battery lost life rather quickly too.
I have just 18 cycles and am down to 41.76Wh, and I have not drained it down to 0%

Though it is not supposed to be very healthy to totally drain the battery every time, I am also of the opinion (like DrMarco) that it probaby does little noticeable harm to drain the battery down once in a while (batteryuniversity even recommends doing a full discharge every once every 30 charges).

I am also wondering if the full charge capacity might be reading incorrectly (like the battery guage can do).
I suppose I will wait and see. I know ibm will send me a new one if this one doesnt last a year. But I'm sure I'll have a 9 cell by then anyway.

[jsmit86]

I'd still suggest not taking it all of the way to 0%.
Your warning will normally kick in at about 10%. But the time you shut down your apps and windows, you will be somewhere around 5-10%.

I would consider that your suggested total drain. Trust me.. going to 0% is not good.

[epigram]

having read the above, i'm convinced that the ultrabay slim batteries are doomed to fail since there are, by design, supposed to drain to 0%, before switching over to the main battery. i can only hope mine fail within the warranty period so that i can get a replacement.

[jsmit86]

This is a bit different. Ultrabay slim is Lithium polymer.
It is also possible that the 0% here is not really 0%.

Since IBM has specifically designed the circuitry in the battey and the pc, they could have left a reserve if it was necessary.

[akerman]

thenew3 - that's normal for li-ion... I don't know what's up with your hp battery, maybe faulty reading.

as jsmit86 pointed out, the ultrabay battery is li-poly - maybe they withstand deep discharges better than li-ion..

[jsmit86]

I have 5 cycles on my Ultrabay slim, with no ill effects.
Design Cap 23.76Wh Charge Cap 24.02Wh

My 6 Cell "normal" battery with 27 cycles

Design Cap 47.52Wh Charge Cap 48.16Wh

My old 6 cell after ONLY ONE complete discharge went to about 40Wh

[epigram]

my ultrabay slim after 67 cycles:
full charge 18.70Wh
design capacity 23.76Wh

when the battery health gauge is yellow, i'm going to call in for a replacement under warranty

[Flightvector]

The full charge capacity is calibrated at the low end after a discharge, this is probably what you are seeing. I don't know why some of you have such degradation after a full discharge unless the batteries were used very shallowly (not a bad thing), and the discharges weren't done for very long periods. This only means that the battery is losing capacity over time irregardless of use (the only real drawback of Li-Ion), but this fact is not discovered until the first discharge is done 3 months later.

Only a couple tenths should be knocking off your design capacity every time. I use my notebook to about 5% charge about once a month; I have only 7 cycles on my current 6-cell battery, which has been fully discharged about 3 times, and my design capacity is 47.62 Whr.

Deep discharges are not good, but discharging to around 5% can be done about once a month, as IBM recommends, to re-calibrate. But since Lithium ion batteries have nearly no memory, you never do need to discharge if this makes you uncomfortable, you may just see a faster initial "decrease" in battery percentage for the first few minutes.

Long term storage in the fully discharged state is the worst thing you could do however; storage at around 50% charge is best for long periods. In a Lithium Ion, batteries will constantly lose potential as a function of time due to oxidation (though heat and storage at discharged state will speed this up quite a bit as well)

[cliff320]

I am currently in the middle of a full discharge (reconditioning)

My full charge was listed at 17 Wh and I've been getting under an hour of power, so i figured I had nothing to lose by trying the reconditioning. It's gone from 5% to 0% in the last half hour and is still going...full charge now says 27.55 Wh, so must be calibrating back to normal now, hehe

the battery is almost two years old, with 95 cycles, and has always been plugged into the wall with rare expection. Let's hope I get above thirty, I'm still waiting for it to finish discharging!

[beeblebrox]

Mislabeling the notebook batteries is consumer fraud.

It is quite interesting to read to different manufaturer's claims about battery life and designed/experienced total capacity. Notebook batteries have built-in intelligence, nevertheless it is on consumer's behalf to be responsible about the survival of a battery. Batteries are a very expensive consumer product and a source of great revenue for the notebook vendors. So, what is going on here?

I had quite an interesting conversation with a technology lawyer recently, which hinted to some tricky questions:

- customers are advised not to drain the battery down to 0%, but something like 5-10%. They are advised not to fully use the product that they bought and had paid for. You get 100% advertised, but are warned not to use more than 90%, otherwise you potentially destroy the item and you might need to buy a new product.

- if that is the case, why is the battery capacity given as 100%, if only 95-90% can be used, to avoid severe damage. The printed label with designed capacity is clearly misinforming customers, a fact that is a potential topic for a class action suit against notebook vendors.

- if the notebook has no electronical prevention to deep-charge down to physically 0% without a hidden barrier to prevent desctruction of the battery it will potentially lead to another class action suit. "Mom and dad" certainly have little clue about battery life.

The Analogon to that fact would be < Don't drive your car until the tank is empty and you run out of gas. Your engine will be severly damaged and might need to be replaced. Always leave 3 gallon of gas in the tank >

Of course, this is what you always do?!

Is it the customer's fault to remember that 100% of a well-paid-for product is not what you should expect to get?

I am quite sure that sooner or later there will be another law suit because of customer fraud.

Just some interesting notes...

[cliff320]

deep discharge #2, the last 5% (though listed initially as 5 minutes), has gone on for 20+ minutes so far. this will be the last reconditioning discharge...update when I return

[kev009]

I think the IBM batteries suffer from poor micro controllers. I'd seem that the extra runtime we experiance during a full run down is not properly accounted for since it takes a deep cycle for it to count which is not reccomended.

[steveho]

This text is from the battery maximer - battery information - battery health - battery tips page:

Reconditioning The Battery
Reconditioning your battery can increase the full charge capacity of your battery. It is recommended that you let the battery run to less than 3% at least once a month.

Occasionally, it may be necessary to "deep cycle" your battery one to three times to give it optimum performance. This will require you to let your battery run completely down, and then to recharge it fully. It is recommended that you charge your ThinkPad overnight for a full charge from a deep recharge condition without leaving your ThinkPad powered on. A brand new battery should be fully charged overnight before its first use.

To do this, perform the following steps:

1. Make sure you have saved all of your data, and close all programs.

2. Disable Power Management timer settings so that your ThinkPad keeps working during reconditioning the battery. You need Administrator or Power User privileges on Windows 2000 or later.


a. Record your current power management settings by clicking these buttons.
to view Battery MaxiMiser power scheme settings.
to view OS power scheme settings.
After reconditioning your battery, you might want to restore these settings to your previous settings.


b. Set Battery MaxiMiser Disable Shut-off Timers scheme, by clicking this button.
to set Disable Shut-off Timers scheme.


3. Disable Hibernation and Standby before a battery is fully discharged, by clicking this button.

to set default low battery alarm settings.
Note that you need Administrator or Power User privileges on Windows 2000 or later.

4. Determine your battery chemistry. It will either be Li-Ion or NiMH.

5. Let the battery totally discharge, then let the battery charge.

Perform the following steps if your battery is Li-Ion:

a. Unplug the AC adapter and let the battery totally discharge. The computer automatically goes to standby mode when the battery is fully discharged.

b. With the proper AC adapter, let charge the battery until Battery LED is solid green.

Perform the following steps if your battery is NiMH:

a. Plug in the proper AC adapter .

b. Click Start Refresh button in the Battery Health dialog to start reconditioning your battery. Battery starts discharging. When battery is fully discharged, it will start charging automatically.

c. When the battery LED is solid green, the charge is completed.

So IBM recommends running the computer until it stops working. That would imply a near 0% discharge.

My computer warns me to switch to a/c power in about 20 minutes. But, if I keep on going, it will go around another 30 minutes (or so). My information on my battery is as follows:
Full charge capacity 4.25Wh
Desigh Capacity 47.52Wh
Cycle count 660
First Use date 2002-10

I'm not sure on how to reset the Full Charge info, as I have followed IBM's instructions, as shown above, and it didn't help.

[Rose]

regarding worn T4x batteries. please look into this WTB-thread.