RCR123A 3v batteries reading 3.7v

[Scottes]

I just tested 6 Tenergy RCR123A LiFePO4 3-volt batteries with my cheap multi-meter. Four were freshly charged within the last 24 hours, and they read 3.72 volts, 3.70, 3.54, and 3.59. I have been using two in my Prodigy since 6 AM, and those read 3.24 and 3.15 volts.

Just to make sure my cheap multi-meter isn't totally whacked, I tested a freshly-charged 18650 at 4.15, and a freshly-charged 14500 at 4.08 volts.

Is this to be expected? I thought these 3v should hit about 3.2v freshly-charged.

 

[Scottes]

I think I found my answer.

From Tenergy RCR123A 3.0V 900mAh Rechargeable Li-Ion Battery

Initial cell voltage of 3.6V switches to 3-3.2V within 12ms.

Since I wasn't putting the battery under load it never switched to 3v.

I guess that I have to test under load.

 

[doots]

yes I think they charge up to that but under load they are not putting that voltage out to the atty.

 

[RenaissancePuffer]

Your LiFePO4 batteries should max charge in the 3.5-3.6V range. They do not however regulate down to 3V. The 900mAh Li-Ion Tenergy RCR123A's that you linked, do however.

I am assuming these are the one's that you have?

2 RCR123A 3.0V 750mAh Rechargeable LiFePO4 Li-Ion Batteries with AC/DC Smart Charger

I haven't tested them under load, but I am pretty sure they're not pushing 7.2V to a used atty, even fresh off the charger.

 

[Scottes]

To clarify, the batteries that I have look like the ones pictured in RP's link, not the ones pictured in my link.


And now that RP has shown me the difference, I'm a little confused.


Tenergy RCR123A 3.0V 900mAh Rechargeable Li-Ion Battery
says "Initial cell voltage of 3.6V switches to 3-3.2V within 12ms."
but RP says they do not.


2 RCR123A 3.0V 750mAh Rechargeable LiFePO4 Li-Ion Batteries with AC/DC Smart Charger
does not say they switch voltage
but RP says they do.


and this link
Tenergy LiFePO4 RCR123A 3.0V 750mAh Rechargeable Battery
*implies* that they switch:

...despite the voltage regulation at it takes the voltage regulation ~12 milliseconds to activate.

and going right to Tenergy's site,
http://www.tenergybattery.com/index...facturer_id=0&option=com_virtuemart&Itemid=27
it does say "Working Voltage:3.2V and Peak Voltage: 3.6V" but nothing about switching.



I think I'm going to keep this simple. I didn't test the voltage under load, so that explains why I didn't get 3v (or 3.2v).

 

[RenaissancePuffer]

What I was trying to say in my post was the 900mAh Li-Ion batteries show as switching after 12ms, but the 750mAh LiFePO4 batteries do not.

I can only assume the LiFePO4 batteries are pushing that voltage (3.2-3.6V) to the devices, or less, under load.