Path: utzoo!attcan!uunet!cs.utexas.edu!wuarchive!udel!ih
From: ih@udel.edu (Charlie Ih)
Newsgroups: sci.electronics
Subject: Re: Car Battery Rechargers
Message-ID: <34203@nigel.ee.udel.edu>
Date: 22 Oct 90 14:06:28 GMT
References: <222556@<1990Oct4> <34700033@ux1.cso.uiuc.edu>
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In article <34700033@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu writes:
>
>........ when it was
>quite clear that the matter involved a device that charges the car
>battery over a period of time, in order to give you a few seconds
>of high current starting power.
> ......

Thanks for setting the fact straight.  In my previous postings, I
calculated that a single alkaline D-cell can transfer 1 amp-hr to the car
battery.  Modern electronics can do this readily and economically.
That is enough to crank an average car (250 A) for 15
second.  Since the posting, I timed my cars and it usually takes
2 - 3 second to start.  So my previous calculation was very conservative.
Of course using a single cell would take too long (appro. one hour).
If we use 4, 6 or 8 cells, the charging time can be reduced to
5 - 15 min.  The set of D-cell can be used several times.

Charles S. Ih,  University of Delaware.