According to Ed Huntress :
"DoN. Nichols" wrote in message
...
According to john :
[ ... ]
A series, parallel connected cells would prematurely discharge into one
another untill they all went dead. It is never a good idea to leave
cells connected in parallel for any extended length of time without
being used.
Certainly a problem -- though less so with an identical batch
of unused cells right from the factory. And assembled into the lantern
battery housing, they should be pretty much all at the same temperature,
which would minimize the problem as well.
Now -- if you added a diode in series with each series string
before paralleling them, you should be fine -- but how much would the
eight diodes add to the cost of the battery? :-)
Not to mention the voltage drop of four diodes in series -- something like
2.8 V? Add more cells... d8-)
That was not what I was suggesting. See below (use a fixed
pitch font to avoid distortion of my ASCII drawing.)
(-) (+)
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
| |
+-:|-:|-:|-:|-||-+
Here I use the more compact notation -:|- in place of the more normal
symbol for a cell of:
|
--| |--
|
and -||- as the closest that I can come to a single diode.
A "(-)" or "(+)" is a polarity sign for a terminal, while a '+'
without parens around it is a junction of two wires at right angles, or
a 90 degree bend in the wire.
So -- there would be only a single diode drop in series with
each series group of four cells -- 0.6 to 0.7 Volts for a silicon diode,
or about 0.15 Volts for a germanium diode (if you can still find those. :-)
Hmm ... what is the forward drop for a copper-oxide rectifier?
It has been ages since I have last seen them used anywhere except in the
rectifier in a multimeter or a panel-mount AC voltmeter -- which may
suggest that it is a pretty low drop. And it might be pretty easy to
make them as part of the strips bussing the cell groupings together.
Enjoy,
DoN.
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