The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
From: firstname.lastname@example.org (Robert Richter)
Subject: Re: Difference between AC adapter and charger?
Date: 23 Oct 2002 05:02:43 -0700
References: <0001HW.B9D43FDF0325BBB11662EAD0@news.covad.net> <0001HW.B9D4EE870344BA681662EAD0@news.covad.net> <3DB01FBB.EAF744F9@usa.net> <0001HW.B9D572FB034E39101662EAD0@news.covad.net> <3DB02E27.email@example.com> <3DB2A987.FA0DD93E@usa.net> <3DB2D4FC.B566FCAE@usa.net> <37ot9.260$FS5.firstname.lastname@example.org>
NNTP-Posting-Date: 23 Oct 2002 12:02:43 GMT
"Peter Gottlieb" wrote in message news:<37ot9.260$FS5.email@example.com>...
> "Robert Richter" wrote in message
> > I took 15V (which is "way too high" for a car battery) to a charged
> > lead acid battery and the current was only 3A. Over-voltage on a lead
> > acid battery simply results in very little current that slowly breaks
> > the water apart and vents the gases (or re-combines them in the
> > maintenance free batteries). Even on a dead battery, it is common to
> > let the internal resistance of the battery be the ONLY source of
> > current limiting, and the alternator can usually handle this because
> > lead acid batteries simply won't charge very rapidly. I have seen
> > lead acid batteries that state "No current limiting needed at 13.8V".
> Leave 15V on a 12V lead battery overnight and bad things can happen. I saw
> this a couple of times with 12V 7 AH sealed batteries which got very hot and
> vented H2SO4 vapor, in one case requiring an evacuation of our offices.
I removesd the vent caps before doing this test (which I did simply
for the purpose of this thread) and it does bubble a bit hard; I would
not recommend such a high overvoltage, especially on a sealed battery;
they don't always have proper venting but rely on re-combining.
> > Very few people make it through life without hearing of a catastrophic
> > failure of a least one friend's car battery.
> Where do you live? I'd like to stay away from that area. Our batteries are
> much more civilized around here.
Not everyone I know is in the upper class and drives a car with less
than 100,000 miles on it.
Galileo being forced to admit the earth was the center of the
universe--after confession, "It still moves, though". As far as NiCd
chargers, maybe they are connected directly to a wall-wart; but after
confessing this fact, "they still aren't charged with a DC voltage"
After this post the thread will die as far as I am concerned.
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup