Re: Battery problems solved, with Lithiums??

Dean Cashen (deanc@hpbs114.boi.hp.com)
Fri, 28 Apr 95 12:17 PDT

[originally from me, deanc@hpbs114.boi.hp.com (Dean Cashen):

> >I read a Consumer Reports a few months ago, and they tested a
> >variety of batteries (NiCad, Alkaline, and Lithium, among them).
> >The found that Lithium provided more energy for devices that
> >needed high, fast output (e.g., flash cameras), and they provided
> >(or promised) longer shelf-life (for apps such as RAM battery back-up).
> >But, they also found that lithium provided NO additional life in
> >applications like walkmen and toys.
>
> The lithiums have a power loss curve that falls off sharply when it falls at
> all. That is good for Zoomer users because the gradual fall in alkalines
> quickly drops the output below what the Zoomer needs. That is also why
> rechargable batteries perform so poorly in the Zoomer. Lithiums provide
> longer usable power for the Zoomer. The Zoomer needs that "high, fast output."
>
> Example:

[nice ascii graph deleted]

You have a very good point regarding the power-curve. Walkmen
and toys don't generally have a low-voltage detection circuit
in them, so when they run down, they . . . run down. Most
walkmen, for instance, will try to keep the motor running
until there's just no power left (the portable CD players
I have detect low battery and shut down; different needs).
So, the steep curve of lithiums may well provide more
usable life than alkalines in devices like the Zoomer
which detect low voltage. I believe this is one of the
reasons why nicads don't perform well in the Zoomer, they
already start out at a lower voltage which subsequently
drops below the Zoomer's "preference" quite early.

Whether the cost-vs-life ratio of lithiums over alkalines is
a good one. . . I suspect not, but it depends on your needs.
Like many of the contributors to this distribution, I get
excellent (almost *amazing*) battery life from my Zoomer,
so I'm pretty content with alkalines.

Regards,
Dean

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