Dell's first attempt to market perpetual motion

No it doesn't.

Graham

Just where exactly does it suggest that?

Just follow this link:

The Flavored Coffee Guy ha escrito:

Please, be serious...

Any lithium battery will explode if defective or improperly charged. No magic there, no thermodynamics law violation.

Which shows a Dell laptop catching fire !

So ? I'm all ears ! Do tell what I'm supposed to infer from that.

Graham

lithium cells have worried me from day one

of course trying to make a clever post without being clever i knew someone would post about the flaming dells but not in such a odd way

well it worked we all fell for the troll

who is more supid? the troll or the first to respond to the troll? or the first person to comment on the troll responder?

From The Register

Laptops roasting it's an open fire Acrid fumes assail your nose Melting chips smell like burning tires and Techs dressed in asbestos clothes

Everybody knows short circuits in a battery Help to make the office bright End users with their cubes all aglow Will find it hard to work tonight

They know a recall's on its way Before the desk is charcoaled in a blaze And every engineer is gonna spy To see if laptops really know how to fry

And so I'm remembering this simple phrase like geeks from one to ninety two Although we dread it many times many ways Yeah, we're getting a Dell, Dude!

Grant

It's a violation of the laws of thermodynamics as soon as something that it's made of melts and it's not supposed to, or something burns when it's not supposed to, even though they built that way.

Then putting new batteries in the computer won't do any good, will it? If it's the charger, it built into the computer, not the battery.

HOW, pray tell? Please try to follow with me on the following brief chain of reasoning.

1. Plastics typically will melt if you get them hot enough.
2. A laptop battery, when charged, contains quite a considerable amount of energy.
3. If you let that energy out in a rapid, uncontrolled fashion, it's not unreasonable to think that things in the immediate vicinity are going to get hot.
4. Given the above, we might expect to see any plastics in the vicinity - including, say, those that formed the case of the battery in question - melting.

OK, at what point in the above did we violate the laws of thermogoddamics?

Bob M.

If you make the assumption that it IS a flaw external to the battery which caused the problem in this particuar case, you'd be right. On what grounds are you assuming this?

(Hint: the statement "any lithium battery will explode if defective or improperly charged" does not equate to "the only thing that can cause the failure of a lithium battery is a bad charger." You DO see that little word "defective" in the above, which refers to the battery itself, right?)

Bob M.

Don't be absurd !

Graham

Most laptop batteries contain the charging circuitry. This is essential since it needs to monitor the battery temperature and *terrminal* voltage precisely in order to charge it quickly and safely.

The ac power unit is just that, not a 'charger' at all.

So, replacing the 'battery' does indeed fix the problem.

Graham

The Flavored Coffee Guy ha escrito:

I=B4m sure you will not understand this link, but anyway here it goes for the benefit of other readers:

Li packs have electronics on board that dictate charge termination (Li batteries are not "floated"). Changing the battery out will introduce new charge termination electronics.

These batteries are "intelligent", they have onboard management which is used to control the charging circuit.

And that affects what I'd said how, exactly?

Bob M.

What's he's saying is the battery contains it own charging circuitry inside. If you change the battery, you're also changing the charger at the same time.

Graham

"Eeyore" wrote in message news: snipped-for-privacy@REMOVETHIS.hotmail.com...

Yes, thank you, that's precisely how I interpreted it, too. The question above still stands, though.

Bob M.