....I don't see 9V Eneloops, unless I am mistaken. I have some 9V
devices that could use the changeout too. Recommendations?

Witherspoon wrote:
=====================
...I don't see 9V Eneloops, unless I am mistaken. I have some 9V
devices that could use the changeout too. Recommendations?

** Don't try any of them in smoke alarms.

Use only alkalines for that.


...... Phil

On 14/02/2021 19:47, Witherspoon wrote:
...I don't see 9V Eneloops, unless I am mistaken.Â* I have some 9V
devices that could use the changeout too.Â* Recommendations?


There plenty to choose from on eBay

If you have a "smart" charger and want to stick with it, there are NiMH
cells out there with capacities up to 900mAH which could be used with
the same charger - like this:

https://www.ebay.co.uk/itm/PP3-MN160...y/193757257679


I believe Charlie+ is correct is saying that if you want to use
rechargeable Li-ion cells, you will need a different charger. If you
stick them in a "normal" charger" it will just tell you that you have a
dud cell. I have seen them with capacites up to 800mAH


Alternatively, there are some Li-ion cells out there which have a built
in charger, and a USB socket on the base, which means that they could be
charged in situ ?

like this:

https://www.ebay.co.uk/itm/PP3-9V-Re...y/143784853806

I would be interested to hear from anybody who has any of these.


Out of interest, you may like to note that I have a couple of Uniross
NiCD PP3 cells, which must be at least 10 years old, but seem to still
work ok - the downside is that the capacity is only 120mAH, but thats
enough for a few hours service on wireless microphone system.

The main point being that all of these current rechargeable solutions
offer at least 4 or 5 times the capacity of the originals, so theres no
need to even think about buying something with a capacity of only 200mAH

Also, dont forget that the original "dumb" chargers had insanely low
constant current charge rates - I have one which runs at only 11mA. At
that rate it would take at least a week to charge one of the latest
generation NiMH cells

AT

Abandoned_Trolley wrote:

=========================

Out of interest, you may like to note that I have a couple of Uniross
NiCD PP3 cells, which must be at least 10 years old, but seem to still
work ok - the downside is that the capacity is only 120mAH, but thats
enough for a few hours service on wireless microphone system.


** The only common application for 9V batts I know of which has both high discharge ( ie 50mA) AND regular use is a radio mic.
I doubt the OP has any of them.....

What else are are high capacity , rechargeable 9V batts good for?

The self discharge rate ruins them for most jobs.


...... Phil

On 15/02/2021 22:01, Phil Allison wrote:
Abandoned_Trolley wrote:

=========================

Out of interest, you may like to note that I have a couple of Uniross
NiCD PP3 cells, which must be at least 10 years old, but seem to still
work ok - the downside is that the capacity is only 120mAH, but thats
enough for a few hours service on wireless microphone system.


** The only common application for 9V batts I know of which has both high discharge ( ie 50mA) AND regular use is a radio mic.
I doubt the OP has any of them.....

What else are are high capacity , rechargeable 9V batts good for?

The self discharge rate ruins them for most jobs.


..... Phil



Well, I have a couple of wireless guitar belt pack things, but I guess
they must use the same sort of technology as wireless microphones ?

The spec for the Trantec model I have quotes a battery drain of 50mA -
so you were spot on with your figure.

A while ago I bought a new battery operated doorbell - one of those
"ding dong - Avon calling" things, which has a single solenoid which
moves out to hit one chime and then gets the other one on the way back.

I was astonished to see that its powered by a 9v battery, and yet more
astonished when I discovered that the 120mAH NiCD will deliver the surge
current required to shift the thing, whereas a 300mAH NiMH will simply
not do the job. I have tried this out with 3 different NiCDs and a
couple of the NiMH cells and the results are consistent.

Obviously the cells are in reasonable condition and have been charged to
death prior to the tests.

Out of curiosity I am going to try out with Li-ion cells to see if the
story is any different. Maybe theres more to this lark than meets the
eye, and its not just about capacity.

AT

In sci.electronics.repair, Phil Allison wrote:
What else are are high capacity , rechargeable 9V batts good for?

Maybe he's got an old transistor radio. I've got a portable tape player
(not cassette, it's open reel) that uses I think two or four C cells for
the motors and a 9V for the "brains".

I gather that there are a bunch of small electronics projects that use
nine volt batteries, too. Arduino 9V battery connectors are something
I've seen for sale a number of times.

Elijah
------
has no personal experience using an Arduino 9V battery connector

Eli the Bearded wrote:
===================
Phil Allison

What else are are high capacity , rechargeable 9V batts good for?

Maybe he's got an old transistor radio. I've got a portable tape player
(not cassette, it's open reel) that uses I think two or four C cells for
the motors and a 9V for the "brains".

** LOL- had one like that when I was 12 years old - in 1964.
3 inch reels , non capstan drive.
The 9V batt lasted well - the C cells, not so much.

I gather that there are a bunch of small electronics projects that use
nine volt batteries, too.

** But not likely to be heavily and regularly used.

My ESR meter ( Bob Parker ) uses a 9V batt - but gets about 1 short use a week.


...... Phil

Abandoned_Trolley wrote:
=======================

Out of interest, you may like to note that I have a couple of Uniross
NiCD PP3 cells, which must be at least 10 years old, but seem to still
work ok - the downside is that the capacity is only 120mAH, but thats
enough for a few hours service on wireless microphone system.


** The only common application for 9V batts I know of which has both high discharge ( ie 50mA) AND regular use is a radio mic.
I doubt the OP has any of them.....

What else are are high capacity , rechargeable 9V batts good for?

The self discharge rate ruins them for most jobs.

Well, I have a couple of wireless guitar belt pack things, but I guess
they must use the same sort of technology as wireless microphones ?

** Of course, just no actual mic capsule.

The spec for the Trantec model I have quotes a battery drain of 50mA -
so you were spot on with your figure.


** I have dealt with a few of the beasts .....

A while ago I bought a new battery operated doorbell - one of those
"ding dong - Avon calling" things, which has a single solenoid which
moves out to hit one chime and then gets the other one on the way back.

I was astonished to see that its powered by a 9v battery, and yet more
astonished when I discovered that the 120mAH NiCD will deliver the surge
current required to shift the thing, whereas a 300mAH NiMH will simply
not do the job. I have tried this out with 3 different NiCDs and a
couple of the NiMH cells and the results are consistent.

** What a POS design !

A fresh 9V alkaline will deliver about 8 amps into a short as will a NiMh.

Have you tried adding a 2,200uF 10V cap in parallel with the batt?
Good for about 0.1 Joules


Out of curiosity I am going to try out with Li-ion cells to see if the
story is any different. Maybe theres more to this lark than meets the
eye, and its not just about capacity.

** Some items draw very high currents, small digital cameras for example.
Alkaline AAs give poor life times, NiMh are far better - but need regular topping up.
Same goes for camera flash guns using AAs.


...... Phil

On 2/14/21 2:47 PM, Witherspoon wrote:
...I don't see 9V Eneloops, unless I am mistaken.Â* I have some 9V
devices that could use the changeout too.Â* Recommendations?

Well, I was considering the other firms making such 9V batteries these
days (Tenergy, etc), but the reviews paint a horrible picture on Amazon.
So, what I did was take the 18650's out of dollar store cell phone
power banks, put two in series for roughly 7.4V, and have been using
that for some 9V items I have. Voltage is a bit low and it almost has
to be mounted externally, but most things I use it with seem happy. And
I kept the charger guts for when they need recharged. Might not look
pretty, but it works and a lot cheaper then even a new 9V alkaline.

On Sun, 14 Feb 2021 14:47:06 -0500, Witherspoon wrote:

...I don't see 9V Eneloops, unless I am mistaken. I have some 9V
devices that could use the changeout too. Recommendations?

I got my parents a starter set of Eneloops a while back and they've been very
impressed. When it came to looking for myself I also noticed a lack of 9V Eneloops.

I've had some decent results with the Amazon Basics 9Vs, but I'm not a very heavy
user. My DMM uses one, and the others are primarily for final testing a type of
guitar preamp that I repair for people.

I'm not sure if they hold up under heavy usage, but considering I use them
infrequently and they're still charged when I do, I can't complain

Bradley Bowman wrote:
====================

I've had some decent results with the Amazon Basics 9Vs, but I'm not a very heavy
user. My DMM uses one, and the others are primarily for final testing a type of
guitar preamp that I repair for people.

** Those are Alkaline types, so non rechargeable.

I'm not sure if they hold up under heavy usage, but considering I use them
infrequently and they're still charged when I do, I can't complain

** Amazon also have a Lithium version with 10 year shelf life.

...... Phil

On Sat, 06 Mar 2021 12:35:55 -0800, Phil Allison wrote:

Bradley Bowman wrote:
====================

I've had some decent results with the Amazon Basics 9Vs, but I'm not a
very heavy user. My DMM uses one, and the others are primarily for
final testing a type of guitar preamp that I repair for people.

** Those are Alkaline types, so non rechargeable.

Ah, my mistake, I was unclear. The ones I'm using are the Amazon Basics Ni-MH
variety. I didn't notice they had Li-ion ones as well when I bought a set.

Bradley Bowman wrote:
==================


I've had some decent results with the Amazon Basics 9Vs, but I'm not a
very heavy user. My DMM uses one, and the others are primarily for
final testing a type of guitar preamp that I repair for people.

** Those are Alkaline types, so non rechargeable.

Ah, my mistake, I was unclear.
The ones I'm using are the Amazon Basics Ni-MH variety.

** In a DMM ??
Don't you get tired of having to recharge it ?

I didn't notice they had Li-ion ones as well when I bought a set.

** Not Li-ion, non rechargeable lithium.

There are lots of sub types of "lithium" - most commonly they are 3V cells.
So three inside a 9V unit.

https://en.wikipedia.org/wiki/Lithiu...es_and_formats


..... Phil

On Sat, 06 Mar 2021 15:42:08 -0800, Phil Allison wrote:

Bradley Bowman wrote:
==================


I've had some decent results with the Amazon Basics 9Vs, but I'm not
a very heavy user. My DMM uses one, and the others are primarily for
final testing a type of guitar preamp that I repair for people.

** Those are Alkaline types, so non rechargeable.

Ah, my mistake, I was unclear.
The ones I'm using are the Amazon Basics Ni-MH variety.

** In a DMM ??
Don't you get tired of having to recharge it ?

Well, no.

That's what impressed me. I didn't really expect them to work as well for me as they
do at a pretty low price point. They might not be the right choice for a heavier
user though.

I didn't notice they had Li-ion ones as well when I bought a set.

** Not Li-ion, non rechargeable lithium.

There are lots of sub types of "lithium" - most commonly they are 3V
cells.
So three inside a 9V unit.

https://en.wikipedia.org/wiki/Lithiu...es_and_formats


.... Phil

Gotcha, I was skimming too quick that day. I see the ones you're talking about
now. After a closer search, I realized the Li-ion 9Vs I saw then weren't Amazon
Basics brand -- though they "looked" like the Amazon Basics at first blush (same
color scheme).