Wouter,

On Thu, 14 Sep 2006 10:58:53 +0200, Wouter van Ooijen wrote:

> I'd said:
> > I read an article many years ago by someone proposing that 
> > the best portable power supply is a single large rechargeable 
> > cell and a boost PSU to produce whatever voltage you want.  
> > The rationale was that by 
> > having more than one cell you never get the best performance, 
> > only that of the 
> > worst cell, and recharging can never balance them properly 
> > without leaving at least one under- or over-charged. 
> 
> I think a counter-argument could be that the loss in the converter is at
> least partially 'constant-voltage', which would hit a low input voltage
> harder than a higher input voltage.

Not sure what you mean by constant voltage in this case - the deeper mysteries of switch-mode PSUs have somewhat passed me by - but obviously 
there would be a higher current-draw from a single cell vs. many cells, so the I^2 R losses would be greater.  But whether that outweighs the ability 
to get the best from the cell would have to be determined by experiment.

Cheers,


Howard Winter
St.Albans, England


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