I recently salvaged a p133st dell xpi from a recycle bin. It's currently running damnsmalllinux. The battery is labelled Li-ion and seems to be holding a charge very nicely.

Never had a laptop before and of course it didn't come with a manual. At the moment it's usually running off the ac adapter with the battery monitor reading 100% charge. Is this good practice?

Yes "Google is my friend" but the truth is I've grown to trust the members here over some anonymous website.

tia for any tips.

Yo wazzup my man!!!!

I would also be interested in knowing. I recently got an old IBM thinkpad T22 (about 6/7 years old, maybe?) and I'm running linux. The battery holds charge well. I haven't tested it much but it looks like I could get roughly 1 hour 30 minutes of life.

I would say you're pretty lucky to have a well working battery in a laptop which is old like that, especially since you got the thing from a bin.

Li-ion batteries are very good versuses the older nicad and nickel metal ones. Li-ion have many pluses like lighter weight and provide a constant voltage output to he end. The cells normally are 3.3v and once 3.0volts is reach it is time to recharge. The battery packs contain electronic circuitry that handles the discharging of the cell pack. In older nicad and others it was recommended to discharge fully every so often to try to eleminate the memory the batteries have during charging and discharging. In Li-ion you never discharge the pack below the 3.0v thershold. If discharged to much then it can in itself self destroy itself. This is the circuitry in those packs. To stop usage of the cell pack when this limit is reached. So it is recommended to store fully charged for periods of time.

Brian

As Brian1 mentioned, it's important to "exercise" your battery by periodically fully charging it and draining it. All rechargeable batteries eventually lose their ability to hold a charge, and while a new battery may be able to hold, say, a 2.5 hour charge, over time (ie, years) it will gradually decline, and you might end up with it only giving you 45 minutes or whatever. Look at cellphone batteries -- when new they seem to last forever, but sooner or later it seems like they're running out of juice every 5 minutes.

What I do is to leave my laptop connected to the AC adaptor as much as possible, and only run off battery when there is no outlet to plug it into. The idea is that I try to minimize the number of charges/recharges over the lifetime of the battery. When I do run off battery though, I generally run it all the way down to where the warning signals come on. This approach seems to be working - I use my laptop almost every day, and the original 6 cell battery still gives me about an hour and 45 minutes of use. (My laptop is an IBM T40, and I bought in early 2004). Compared to some of my coworkers who apparently only plug in the AC adapator when they need to recharge, they're on their second or third battery in that same timespan.

On a slightly different topic, I'd recommend the *excellent* utility gkrellm to help monitor your entire system, including the battery level

OK. Now I've heard this advice from you, I shall use my laptop on the battery until the warning signs come up (like to 5% charge level, right? Or what do you suggest?); I shall do this once every month from now on.
Would you say that this is too many times, or too much, or too little? I'd like your opinion on this, since you've managed to get your laptop battery live a long life; touch of the master's hand.

What you've outlined is more or less what I end up doing, not so much according to a schedule but rather that's just how things work out. In any case, when running the battery down, I let it go all the way down to where the little alarms start going off, at about the 4%-5% mark. Note: you don't want to have the battery completely drain to the point where the laptop just powers off... that would be basically the same as just yanking the power cord out of a desktop, and obviously that's not good, and you can risk data corruption. When recharging it, if possible I try to let it recharge fully (eg, let it recharge overnight)

Just to make things clear, it's not like I'm any kind of expert on this topic. I'd like to consider myself well-informed, but it's not as if I have any particular deep-level knowledge and experience. That said however, I can say that rechargeable batteries don't last forever, and as they age their performance tends to degrade, ie, the decline seems to be a function of how many times they've been recharged. Therefore, it makes sense to me to try to avoid draining&recharging the battery unnecessarily. You do want to "exercise" the battery from time to time, but personally I don't obsess about it. Heck, maybe I just lucked out and my T40 came with an especially good battery

Batteries have a limited number of cycles they can be used and partial charges and discharges can add up to full cycles so you cna discharge half was twice and its counted as a full cycle. Every could months it might be a good idea to discharge completely to let the matter meter get re-calibrated, but thats somewhat laptop dependant, if you start to see shorter run times after a month then discharge conpletely to get the gauge reset. But in genral any modern battery doesn't need/want to be fully discharged and fully discharging will just use up charge cycles.

Thanks for that and also to everyone else that replied.

One final (I promise) question. While running off AC damnsmalls battery monitor often shows "charging 99%" then returns to "battery fully charged". Is this chewing up this batteries remaining cycles? Possibly a sign the battery is near the end of it's life?

And you're right PatrickMay16, it's a bit of a wonder the battery worked at all.

You shouldn't have your battery in your laptop while running on AC. Read up on why that is on Wikipedia. While you're not using it, let it charge to 55% and dump it in the fridge at 15°C (60°F) in a plastic bag.

Which article specifically? (just searching "laptop batteries" brought up lots...)
can you give a link?

thanks

They get warm running on AC and the battery. The bottom might cause burns and according to some doctors the laptop can heat up the scrotum which could affect the quality and quantity of men's sperm.
http://www.smh.com.au/articles/2004/...182401714.html

Not sure what you gain by doing this. This will not change the operating performance of the battery. It will keep the outside case cooler a little longer but IMO since most fridges are at 35-40 deg F turning the laptop on right after pulling it out might produce condensation which could damage the unit.

michaelk, you are right, of course. I failed to mention that putting it in the fridge is for long-term storage (few days or more). After taking it out it needs to reach room temperature before it's used, obviously.

User with bad nickname, check out this article:
http://en.wikipedia.org/wiki/LiIon#G...n_battery_life

The issue with the battery getting too warm is laptop specific. Decent laptops will be properly designed to as not let the battery get too warm, but the cheap consumer grade ones might.
But running a laptop without a battery is kind of pointless, you might as well just use a desktop.

enine, it isn't pointless at all! The typical desktop box uses 10 times more electricity than its laptop equivalent, so conciously avoiding the desktop is not only environmentally friendly, but also good for your finances

A desktop doesn't use anywhere near 10 times a laptop. And with all thses cheap consumer grade laptops with wide screens and desktop cpu's they are even closer. My wife had one of those crappy Dell Inspirons with a desktop cpu and it wouldn't even run off a 300W inverter and I've had desktops with 150w power supplies. So I've seen desktops that even use less that some laptops.