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Smitty Two

In article ,
wrote:

The most you can deplete a ni-cad battery's full-charge voltage, by
subjecting it to less than perfect charge/discharge cycles, is a measly
5%. Can you name a battery-powered gadget that won't operate at 95% of
its design voltage?

You seem to ignore that a battery under load may measure a different
voltage that you example above. Read below.

So Ni-Cads are perpetual voltage?

I don't really think you think I said that, so why are you saying it?

You suggested that a no load Ni-Cad at 95% voltage will run any
consumer device. It won't if the device draws a sizable current and
the Ni-Cad is in poor condition because of to many recharge cycles, or
repeated light charges. A N i-Cad in this condition will look good on
your voltmeter but will fail in use because of an immediate voltage
drop upon actual use.

95% of voltage is NOT 95% of capacity.

I didn't say that, either. Capacity is rated in milliamp-hours, usually.
But a *full charge* is indeed measured in volts, which is what I said.
It's going to be difficult to have a discussion if you twist what I say
to suit your own reasons for postulating a different point of view.

And milliamp-hours diminish with a poorly treated Ni-Cad. That is why
I pointed out that your no load 95% voltage Ni-Cad measurement is
useless. It doesn't tell us anything about the actual capacity.

I'll accept my part in the miscommunication. I'm aware of load vs.
no-load differences, and never suggested otherwise. Certainly batteries
wear out.

Call it capacity if you like, or voltage at rated load, or whatever you
want -- a ni-cad suffers no more than 5% from being "mistreated" in it's
charge/discharge cycles. And any engineer who follows design parameters
without significantly more margin of error than that, is an idiot.

I still assert that the ni-cad charging "wisdom" is myth, period. And
you're still welcome to disagree, if you do. But you won't have science
on your side.