Date:         Sat, 26 May 2001 12:38:31 -0500
Reply-To:     Marshall Ruskin <mjruskin@HOME.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Marshall Ruskin <mjruskin@HOME.COM>
Subject:      Re: Solar Panel "Battery Saver"
Comments: To: Kitzmann <kitzmann@EXIS.NET>
Content-Type: text/plain; charset="iso-8859-1"

I am enjoying this thread....

In absolute darkness, I think the reverse path (from the battery to the
photovoltaic cell) is near infinity - hence an open circuit.

But what happens when there is a small amount of light impinging upon the PV
cell?

I think it will prolly be biased slightly forward - and yet not produce a
significant current flow.

In that case, there is prolly a reverse current throught the PV cell, hence
it will act as a load on the battery.

As listees have suggested, a diode that can handle the forward current of
the PV cell, will prevent the reverse current path, and the degradation of
the battery's charge.

Marshall Ruskin

> There is usually a diode in the circuit that will only allow current to
> flow one way through the panel.  If not, I believe that the panel will act
> as a high resistance load and will drain power from the battery.
>
> Dave K.
>
>
> >
> >If I recall correctly from my optoelectronics class, (10 years ago)
current
> >won't flow backward through a photovoltaic cell, wich has a battery
> >connected as a load, because the photocell is reverse biased with respect
to
> >the battery.
> >
> >I bet Darrell Boehler, if he reads this, will know for sure.
> >
> >Marshall Ruskin
> >84 Westy