On 18/11/2020 02:42:32, Nick Cat wrote:
On Wednesday, 11 November 2020 at 20:36:34 UTC, Fredxx wrote:
On 11/11/2020 03:13:29, tabby wrote:
On Tuesday, 10 November 2020 11:10:41 UTC, Fredxx wrote:
On 10/11/2020 03:04:36, tabbypurr wrote:
On Monday, 9 November 2020 10:16:51 UTC, Martin Brown wrote:
On 08/11/2020 13:59, Fredxx wrote:
On 08/11/2020 13:42:21, Scott wrote:

My multimeter has a battery test facility that shows
the battery as good or bad (or on the margin). I
understand a zinc carbon battery has a voltage of 1.5
Volts and an alkaline battery has a voltage of 1.2
Volts? How does it know the difference between a very
good alkaline battery and a very bad zinc carbon
battery?.

An alkaline battery also has a nominal o/c voltage of
1.5V

A good fresh alkaline can be as high as 1.6v open circuit.

They start off above 1.5v. 1.5v is only nominal.

A well used one can go as high as 1.8v under odd
circumstances. I had a couple do that earlier this year. They
were well used then recharged, and gave a strangely high
output. No idea why, none of the others did.

Most articles suggest a brand new alkaline battery starts at
1.65V o/c and goes down from there.

Do you have reference you can cite for a well used one with a
o/c voltage of 1.8V?

no, haven't looked.
I have and 1.65 is the highest I saw for a new battery. An old
battery will typically be 1V.

these weren't new batteries

The only odd circumstance I can think of will be a duff meter.

I told you what the circumstances were. The meter's fine. But
feel free to get stupid again.
Perhaps it was user error then, or not recognising a malfunctioning
meter?

no

If you have any non "stupid" reason for the erroneous measurement,
please do let us know.

the measurement was not erroneous. Did I not already mention the
cells had just been recharged?

No you didn't. Unless you're a sock pretending to be someone else and
think you have?

Short term overvoltage after charge is
a routine phenomenon. Any EE knows this.

Any EE would know that the alkaline batteries referred to by Scott and
myself were primary cells. Rechargeable alkaline never caught on for
being so poor in so many ways.

1.8v is unusually high but
there ya go, consistency is not something that happens with
post-charge voltage. Did we not cover this already? Yes I did:

You might well have done, which can only be explained as an entirely
different chemistry to the standard alkaline battery discussed here.

A well used one can go as high as 1.8v under odd circumstances. I
had a couple do that earlier this year. They were well used then
recharged, and gave a strangely high output. No idea why, none of
the others did.

You never did answer the question, "Was this battery mixed in with a lot
of other batteries?"

A good rule is don't let your insatiable desire to be right get in the
way of facts. The alternative is to look a plonker.