CR123A Batteries

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Is there a part number on the camera batteries?

As it turns out, I decided to climb the ladder and see what battery was in the station. It's identical to the 123. If I look closely at the package, it shows the 123 is a replacement for several 123s, including the CR123A.

When I put the new battery > >

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                          Wayne Watson (Nevada City, CA)

                        Web Page:

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Could be the battery voltage is low under load, or the threshold
voltage is set wrong in the device.

BTW, please bottom post.

The 'chemistry'.

That's the difference between primary and secondary cells..

Graham

I have this very same weather station. I put it on top of my 40Ft radio tower in November. The battery is a standard 123A lithium battery and the Duracell you mention is the same type. It is a 3V battery. I use the batteries in a few different high intensity flashlights, new they have a voltage of just over 3V like you said yours has. I believe the number of the battery indicates that it is a single cell (1) 2/3 length (23) A size battery. 'A' is a standard battery size just like D, C, AA, AAA etc, just not as common and generally only found in rechargeable NiCd, NiMH or Lithium Ion cells.

It is my understanding that the solar cell on the standard Vantage 2 pro simply augments the battery when the sun is up and I think it may charge a capacitor to help for a short time after the sun is down. My station will give the same low battery warning from time to time. It only does the low battery check once a day. On my station it will often go away right after midnight. Not sure why the low battery warning comes and goes. Next time I tilt my radio tower down, I will replace it just in case but I have heard of people getting over 3 years of use from their stations when they are exposed to lots of sunlight.

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Chris W
KE5GIX

"Protect your digital freedom and privacy, eliminate DRM,
learn more at http://www.defectivebydesign.org/what_is_drm"

Ham Radio Repeater Database.
http://hrrdb.com

I forgot to specifically state that these batteries are NOT rechargeable.

Just wanted to be clear on that.

--
Chris W
KE5GIX

"Protect your digital freedom and privacy, eliminate DRM,
learn more at http://www.defectivebydesign.org/what_is_drm"

Ham Radio Repeater Database.
http://hrrdb.com

I've used CR123A batteries in designs - lithium - and only ever saw non rechargeable types. It is a REALLY BAD IDEA to try and charge a non rechargeable lithium battery, like a standard camera one, in fact here in the UK there is a law that if you have one in a circuit where there's another power source, you need to have not one but two things in series to minimise the chance of accidental recharging. For example 2 diodes or a diode plus a quite high value resistor.

The reason is that these types of cells are sealed and can't vent if the internal pressure gets too high from unwisely recharging them, so unlike normal batteries (AA, say) they go spectacularly and dangerously BANG when they blow.

These types of cell in much equipment are just there as a backup supply for when the primary power source goes, thus last years (eg on some PC motherboards, they just power the real time clock).

Also be aware: there are two chemistries, LiMnO2 (lithium manganese dioxide), nominally 3.0V, actually about 3.2V when very new, can drop to

2.8V when very cold. Then there's lithium thionyl chloride which is 3.6V, but not favoured for various reasons eg worse for environment, fewer suppliers, lower peak current output. If your equipment was originally using a 3.6V battery then yes, 3.02V is possibly "low".

I'm not ruling out the possibility of rechargeable CR123A's but if the battery says "LiMnO2" on it it is not rechargeable.

I've also designed with rechargeable lithium cells, these are normally

4.2V when full, 3.0V would be flat. They have a completely different chemistry inside, which includes lithium. Unlike one-use lithium cells, recharging these "undoes" the chemical reaction inside them and physically unbinds the chemicals inside that combined to give the electric current when you ran it down. Many chemistries are not easily reversible. (You CAN recharge a normal battery, but it'll only last perhaps 10 cycles, and will have poor capacity / peak current etc, and you better be sure it's got a safety vent.)

What does the Davis website recommend for replacement batteries?

Any other marking on the original battery?

Paul Honigmann

In article , W. Watson writes