Battery Degradation over time

Hi...

I was looking at the Lenov Toolbox earlier today and was going through the diagnostics. I find that while the health status of my battery is reported as "good", its capacity has fallen to about 86%. This machine will be one year old sometime in March/April.

Is this not a bit of a drastic fall for a battery that is not even a year old? Or, is this normal. Generally, about three times a week the I use the battery - but I seem to use it till about 50%. By that time, I am back at a desk when I can plug in. I have set the battery to "optimize for battery life" in the power manager and I have created my own power plan to gain max battery life.

While I have set power manager to reset the battery automatically and to inform me when it does so - I have not yet seen a notification to that effect. Should I reset the battery manually?

Thanks

 

It seems pretty normal to me.

 

Well, TPM reports 86% of the initial battery capacity too in my z61m, but it is now almost 4 year in use (the battery was made by Panasonic).

 

how many charge cycle have you gone through? also have you tried Thinkvantage Power Manager to do a battery reset?

 

Do you mean your battery will only fully charge to 86%? My 3.5+ years old Z61m stock battery will still charge all the way to 100%. I only had about 90 cycles on it so far.

 

Cycle count is 26. And, as mentioned above, I have not done a battery reset though I have set in PM to do it by itself and to let me know. Should I do a battery reset?

 

No, it charges to 100%, but reports about 86% of the initial capacity when unplugged (displaying a black triangle icon next to the battery one).
(I've just checked - it has accomplished 591 cycles and was used in January 26th, 2007 for the first time).

 

yes have a try.

 

This will take a couple of hours...I'll do this after work tomorrow and I'll report back with the results.

Btw, unlike the case of "menos" there is no black triangle icon that I can see.

 

For me, I have an original design capacity of 84.24 Wh, and a current max charge capacity of 66.85 Wh, which is 79% of the original. I have used it for 56 cycles. Cell supplier is Sanyo, and manufacture date is 11/03/2008. My results seem more or less in line with yours, so perhaps it is time for me to do a reset as well.

 

Apparently, this battery reset takes a hell of a lot of time. First it discharges, then it charges back and then something else. All this is accompanied by the warning to avoid using the machine while this resetting is taking place. I would have loved to do the reset tonight, but I have to work through the night and will be using the machine. I will do the reset tomorrow after I get back from work.

In the interim, if you do the reset, would you please let us know how things went and if there was at all any difference? Thanks.

 

Mine was similar, actually maybe worse, I think after a year it went down to under 80%. I think Lenovo used poor battery technology and so we have such a high incidence of people replacing Lenovo batteries.

 

So, did you replace your battery?

I also saw mentioned in the Lenovo Tool Box that the warranty of my battery has expired, which I find strange. But whatever! It's maybe 60 days or so off. And anyways the warranty was only for a year (for the battery, that is).

Currently I get about 2.5 hrs of work done (wifi on, brightness reduced to half) and reach around the 50% mark. So, I am guessing that I could get about 4 hrs (maybe a bit longer if I push it) before the battery drains out.

As long as my battery is able to give me that with a buffer of about another 30 mins, I should be fine. If not, I'll have to buy a new battery. But first things first, I will do a battery reset and see what happens.

Also, I have a few questions about Power Manager and the Lenovo Tool Box.

When I look at the information in Power Manager, under the Battery tab, I see the following:

Design capacity: 56.16 Wh
Full Charge Capacity: 48.03 Wh
Remaining Capacity: 47.42 Wh.

So, question is: What is the difference between "design capacity" and "Full charge capacity"? And, why is there a difference between these numbers?

Second question:

When I open up Lenovo Toolbox and look within the System Health tile and at the Battery Performance option, it shows that the % of original capacity left is 86%. So, my question is - 86% of what? Is it design capacity?

Thanks

 

Yeah I replaced mine. At first I got the Boston power battery but I returned it, so I bought the regular Lenovo 9 cell.

Full charge capacity means that's how much energy the battery can store right now, design capacity is how much the battery was designed to hold (aka, what amount it should have had when it came from the factory, although they usually have a little less charge than that when they come out of the factory).

It is 86% of the design capacity, yes.

 

So the difference between design capacity and full chanrge capacity is the amount the battery has degraded over the period of ownership. Correct?

You have a T61 with a 9 cell. It must be heavy right? If I am compelled to buy a new battery for this machine, then I may also opt for the 9 cell. I just wonder how much heavier (in real life) it would be!!!

 

Yes that is correct.

I don't mind the weight too much. I think it's about .5 lbs difference between the 6 cell and 9 cell. It doesn't bother me too much because I wouldn't carry around much else besides my laptop and AC adapter. (notebook and pencils and that's about it).
I was certainly surprised to learn that the 17 inch Macbook Pro was similar in size and weight to my laptop w/ 9 cell. Earlier in the year I thought I would get one (I wanted more screen real estate but with the same size and weight as my current laptop) at some point but I'm living with what I have for now.

 

Hmmm. I did a complete recharge this week and it went fine and was completely automated.

I did the recalibration for a reason. I have a like new t61p nine cell battery. By calendar time it's about 1.5 years old. It's sounds like another old battery story. The thing is that I got more than four hours from my other nine cell. I have never gotten near that with this one from Lenovo (new yet).The battery onlyhas 20 cycles on it as I have rarely used it. I get like 2 hours time from it. I've thought about writing to Lenovo on this. Should I?

Renee

 

Mine is around 3.5 years old with 90+ cycles. Does 83% of designed capacity sound reasonable?

 

That's pretty good for 3.5 years, I'm just shocked that you only have 90 cycles. That's about 30 cycles a year, so I guess you only use your battery once every 12 days?

 

If its under warranty and you think it is underperforming, you should.

 

That's trouble. Although the battery has been bad, I have waited beyond the warranty period, to do anything about it. However, the low number of recycles does indicate that the battery has not been used.

Renee

 

batteries are a wear item.   if you don't use them they will degrade faster than if you do.   most of the failed batteries i've encountered in various systems (hundreds, in fact) have had low cycle counts.

you aren't doing a battery any justice by not using it.

 

I realize that Erik. But it's a little difficult to use if there are only two hours of time on it.

Renee

 

Yeah...sorry, I missed that part where you wrote that the batteyr was about 1.5 yrs old. Well, I think that you may have missed the bus on this one and your only option is to look for a new battery. Maybe on eBay?

 

No, I'll purchase one from lenovo...but I won't know if it's any goood, because it's from lenovo.

 

But at least it will be under warranty (at least for 1 year) and you could get it changed if you find there is something wrong with it.

Edit: I am still to do the battery reset. Maybe tomorrow.

 

Your correct about that. It took a while to dawn on me that the battery was bad. My error...

Renee