Hello people,

First, not sure if this should be here or in the General forum, since this doesn't seem to be related to Linux (or software), but rather a pure hardware issue, so if the mods think this suits better in General it's fine by me.

I have a Lenovo G460 laptop. Since it was going to be unused for months (or occasionally used at home without the need of the battery), I waited for the battery to be charged around 45%, took it out of the laptop and placed it in a box for months. (I read this would be useful to save battery life). Yesterday I put the battery in the laptop again and right after switching it on and booting Debian, the KDE battery indicator showed it was charged at 9%, which made me think the battery had gotten discharged somehow, even if it was not in use. I used the laptop for some time (maybe 50 minutes) and the battery was charging normally, but after reaching 79%, it just sat there and didn't charge more than that. I booted Windows 7 on this same laptop and it shows 80% instead, but the behaviour is the same (it won't charge more than 80%). Besides, when I hover my mouse over the Windows' battery indicator, it says something like "Connected, not charging". BTW, the battery sticker says it's of the Li-ion type, in case it's relevant.

I did a web search for this problem, and according to some people in another forum, taking the battery out of the laptop while it is connected to the wall socket and running, waiting 2 minutes and putting it in again, fixes this issue, but I'm not sure whether it might damage the battery, or worse, some laptop component.

So, the question is, does anyone know how to solve this? Also, information regarding why this happened and how to avoid it would be useful in the future.

Regards and thanks in advance for any help!

try to discarge battery first?

1 members found this post helpful.

Hello yooy,

Okay, will try that. I'll let you know how it works.

Thanks for your help!

I had a similar problem with a laptop battery. One thing I discovered is that although my battery wouldn't charge beyond 60%, it seem to last for an hour or more when it got down to 5%. In other words the electronics was giving bogus information about its charge state. I didn't find a way to fix that, but at least I could set my battery alarm down to 2%.

1 members found this post helpful.

I'm under the impression this might be a similar problem. I disconnected the AC adapter in order to have the battery discharged, and currently the battery indicator shows 70% and says there are 2:23 hours remainig (can't remember how much did it last before with a similar charge, though). Will have to wait some hours to see if discharging the battery solves the problem.

My one laptop does that as well, but on that, it's truly an issue with the battery. It's dying and I really need to get a replacement.

It's not recommended to discharge a Lith-ion battery completely. Frequent partial discharges are better than sporadic full discharges.

To the OP, I wouldn't be too worried. It's very unlikely that the battery is damaged. It's more likely that it needs recalibration.

Recharge the battery completely, with laptop switched off. Then turn the laptop on and discharge it to 20%. Then turn the laptop off again and recharge completely. If it goes to at least 90% it should be ok.

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Thanks, ottavio. I'll try your suggestion. (Luckily it didn't get completely discharged because I had to go out and the laptop entered in sleep mode).

Thanks for your help folks, I'll keep you posted.

Hi again folks,

I did another web search and found this thread on the Lenovo forums. The battery has a system that allows the user to optimize it to preserve lifespan, which only allows it to be charged to 80%. For some reason, the battery switched itself to this mode and that's what was preventing it to get fully charged. Not sure how it switched itself to the lifespan preservation mode, since the software that allows to control the battery was not even installed... maybe the battery defaulted to this mode when I reinstalled Win7 and wiped all the programs it had installed. It's charging correctly now (it's at 90% at the moment). Do you think it's advisable to use this lifespan preservation mode? I will use it mainly in places with access to a wall socket, so it not getting fully charged wouldn't be a problem (and I could switch it to the other mode and charge it completely in case I need to take it somewhere else).

Regards and thanks a lot for your help, people!

Yes I do think it is advisable. I'll probably get shot down in flames for this, it has happened once before already, but I'll say it anyway. Rechargeable batteries (lead-acid batteries are the exception) develop, for the want of a better term, a memory. If you keep discharging the battery to the same point and only chanrge it to a certain point the battery memorises this and you lose the rest of the capacity. If your laptop has a preservation mode the manufacturer has made it easier for you to keep your battery from developing a "memory". Regular, not everyday or even once a week but certainly once a month or so, discharge-recharge cycles to different points within the batteries capacity will help it "live" a longer and more fulfilling life.

So, I'd be using the preservation mode if I had it just to help maintain the battery and help it live longer.

1 members found this post helpful.

Thanks for the advice and the explanation, k3lt01. I will use mostly the preservation mode then and only use the runtime mode when I need to take the laptop outside.

Regards.

I realize this is a late comment on the thread, but... Lithium batteries do not really have the same issue with memory that NiCads do. The problems with Lithiums occur with either discharging ANY SINGLE CELL completely, or overcharging ANY SINGLE CELL. If you don't have a balancing charging system, that attends to the cells individually, you get things like premature battery death or, on occasion, fires and such. Presumably the battery preservation system tries to address this somehow, but if all it ever does is not charge the system over 80%, I'm not sure that helps things a lot: the inter-cell discrepencies that are the problem will crop up more or less just as quickly with that approach, I think... it may help avoid overcharging, but at the cost of forshortened battery life, I would expect. But without knowing more about that mode, we're sort of just guessing.

Keith

1 members found this post helpful.

Hi Keith, thanks for the explanation.

Since I generally use the laptop in my room, I'm currently using it without the battery attached. In case I need to take it somewhere else, I will use the runtime mode.

Cheers!