Thinkpads Forum

Hey folks. I need to hear about your oppinions again--this time about the battery using habit.

After using my X41t for about 7 months, i was stunned finding out that battery life became plummetted all the way down around 40% of the original capacity.

Maybe the battery was a defective one. I called one of the reps and will get a new one, thanks to IBM's great quality service.

But now I come to be more cautious on this. cause battery warranty is almost ending. I cannot do this again to the new battery. So, what should I do?

Before asking you some advice I may have to let you know what I have done to the battery.

1. I set the power manager to charge 100% all the time.
2. and plugged it to AC whenever I wanted to.
3. I used standby all the time; only once in a while I rebooted.
4. seldom used hibernation; u know hdd in x41t is slow.

In the end, my battery seems to be suffered a lot from these configurations and my personal habit. Don't know which one was the big factor, but i'm sure i don't want to do neither of them.


What I know is that it is always good to reset the battery. I do that occasionally and I will do that. I also know that it is good to reset it a couple of time with the new battery. I'll do that.

Besides them, what should I do with my everyday usage of TP and its battery? Let it recharge only when it goes down, say, under 10%?

Greetings,

http://www.laptop-battery-resource.com/ ... eries.html

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.
Jeremy

thanks jeremy

heiss wrote:thanks jeremy

Greetings,

You are welcome.

Jeremy

The battery wizard in many recent TPs (like T4x, R5x etc) has a function to recondition the battery. I used it on the battery of an R51 which was in 'yellow' condition (that is, somewhat below design wattage) and its maximum charge increased by 15%, back into the green (when the machine is reconditioning the battery, you are supposed to leave it unattended, the software will then run several controlled discharge/charge cycles). In my T42, the battery is actually at *more* than the design wattage (it shows a capacity of 48.16 Wh and a design capacity of 47.52 Wh; this is after 48 cycles and 22 months). I am in the habit of setting it to recharge only after it has reached 85 or 90 percent charge during slow discharge (all batteries, even when on AC, tend to self-discharge slowly). Apparently this is better for the battery as it avoids an excessive number of unneccessary small cycles. I always keep the battery in the machine when working on AC power (which is 95% of the time), and the present capacity should be proof that it has no detrimental effect whatsoever.

Jeremy Tan mentions that heat is a detrimental factor to the battery. I use Centrino Hardware Control (now called Notebook Hardware Control) to downvolt the CPU (mildly), which does noticeably cool the machine. Plus it is usually in a Minidock, which allows better heat dissipation from the underside. Maybe running a notebook at full power, i.e. hot, on one's lap and/or nicely padded hotel beds has a detrimental effect?

had the same problem. solution: use the faulty baterry and keep the new one in a cold place (cellar, even frege some says) and use it when needed.

it seems the the bigest problem as mentioned is the heat, and if you use fan control you will see its about 37-40 degrees in the battery compartment...that's the problem all laptops have

dorin

When I got my used X31, I used it for about a week before checking out it's condition. It showed it in the red and recommended deep cycling it 1 to 3 times to recondition it. I did it twice, but it's still in the red and now it seems like it only lasts about 1/2 to 2/3 as long as it did before I deep cycled it. Maybe the recalibration actually discalibrated it, as in my last laptop where the battery would shoot down to 7% in about 10 minutes, then last another 30. I haven't tried seeing how long the last few percentages last with this one (though when deep-cycling they seemed to last longer). Anyway, I'm not so sure that deep cycling is as non-harmful a procedure as reported. Admittedly, I think the battery may be the original from 2 years ago.