Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[psyn]

I think you failed to grasp the main point. Lithium-ion batteries lose (or lost until very recently) capacity many times the normal rate at peak charge when not charging (edit: or charging, it matters not) due to elevated internal oxidation. It's the precise opposite of a car battery. Purchasing a second-hand laptop that was sitting unused for many months is guaranteed to have a (sometimes drastically) reduced capacity because the owner thought fully-charged = Good Thing.

As for heat, unless you live in the Sahara desert, the battery of some powerful laptops can easily reach 50-70C under high load while poorly ventilated (i.e., 1/6" bottom airflow).

[Shades]

You realise your article was from 2003, and was out of date on the latest technology even then but a reasonable article considering when it was written and what was around, and it is talking a year of storage there not the short term people tend to go between usage.

The OP mentioned a period of 2 weeks, even if you double that you don't get the degradation he is talking about unless it's a damaged battery.

Yes if your storing long term then don't leave it charged.

[psyn]

I don't know why I'm arguing capacity loss; it's common knowledge. I'm sure you can find a citation from a recent battery manufacturer if you look hard enough.

I didn't address the OP. I specifically wrote heavy loss after 1-4 months for a 1-2 year old (read: already nearing its lifespan) li-ion battery. It could be coincidence, but I lost two older li-ions this way when they were left inside the garage for the summer (90-110F). That Pentium4 battery died after 6 months of continuous plugged-in use (~120-130F). It's happened 3-4 times to various other people I know. If it were totally dead in only two weeks, I'd probably assume it was left sitting depleted.

But whatever... ultimately, it's an easily-replaced and inexpensive battery. I don't consider it a worthwhile topic to get into an argument over.

[Muz]

As an electrical engineer, I'm quite pissed off with people giving off all this false knowledge.

Car batteries love being charged and hate being empty. Lithium-ion hates being fully charged and likes being discharged. I think everyone knows that and "common knowledge" is based on that.

Now here's something that common knowledge seems to forget:
1. If you let your battery die, it will be permanently damaged. Discharging is nice.. but if you ever let it run out, it's broken.
2. Battery chargers are designed to keep your battery charged in a way for it to remain healthy. Removing batteries does not improve lifetime in a modern machine. This is also why battery chargers and batteries are very pricey. If you buy an imitation, uncertified charger or battery, your battery will die or blow up unless you put special effort into making sure it doesn't and you fucking deserve it. Seriously, the cheapest (and safest) thing you can do is buy an expensive battery/charger.
3. If you're going to store it, store it at about half charge. Full charge will weaken it, but shouldn't be a critical problem. I do it a lot on full, and even 3 years later, all my laptop batteries work fine. If you store your battery while it's empty it will die. 40% is good, 15% is VERY BAD.
4. It's fine to pull out your battery from your laptop when you're using it. But remember that when you pull your battery, it's not getting the charge-discharge exercise that your charger gives it. Instead, you're storing them aside at full capacity. This is fine if you plug it in again sometimes, but if you go for like many months with your battery put aside, not good.


I've never had a problem with my laptop or cellphone batteries. All of them last fine up to the point I stop using the laptop/phone. The ones that do get damaged are the ones that I leave nearly/completely empty because I'm too lazy to charge them a little. Electrical engineers really try to design products that last longest with "normal" use, meaning that you shouldn't have to pull your battery out or keep it in the fridge and stuff.

On the contrary, some people prefer to listen to "common knowledge", pull out their battery from the laptop when using the laptop, etc, and they complain that their batteries still don't last. There is some correlation there.