Tenergy '3v' 900maH cell okay at 3.87v?

[novice]

I'm making my first foray into rechargeable Li-ion cells. I decided to go with the Tenergy '3.v' RCR123a '900maH' cells, for use in some of my SF hosts using Malkoff drop-ins, and in my A2 once Koala's led ring comes out (I so hope FM's strion adapter and Koala's ring work together).

The Tenergy charger that comes with these cells looks a little cheap. I would have preferred to spend a little more to get a higher-end charger, but I am aware that you have to be very careful about what cell you can charge on which charger, and I'm going to stick with the 'official' charger. The Tenergy charger has this funky gradually-changing-from-red-light-to-green-light-in-the-same-indicator-window, that can look different depending on which angle you view it from, so I got my first DMM (the $4.99 harbor freight special), so that I could check the voltage.

Battery Junction lists this Tenergy cell as being 3.6v (fresh off of the charger?), dropping down to 3.2v under load. I charged 2 cells yesterday until the indicator appeared to be more 'greenish' than 'reddish', and those cells now both read on my DMM at 3.85 volts (at least they both match). 2 other cells I pulled from the charger several hours ago read at 3.87v.

Does that voltage appear to be within acceptable bounds for this particular cell, or is it excessive?
Also, can someone give me a rough idea of the self-discharge rate?

Thank you!

 

[45/70]

Hi novice. Measuring the OC voltage of 3 Volt LiCo cells is difficult. The diodes that are used to lower the voltage when the cells are under load tend to throw off voltage measurement.

Your readings are pretty close to what I get with my Powerizer and AW 3 Volt LiCo's. Depending on the meter used, I can sometimes, after several tries, actually get 4.20 Volts when the cells are fully charged. This happens when the load the meter puts on the cell is low enough that the diodes don't come into play. On the other hand, when the diodes do affect the meter reading, depending on the meter used, you will usually get readings similar to what you're getting. The voltage will vary a bit between different meters, as the load they apply differs as well.

Personally, I'm replacing all my 3 Volt LiCo cells with LiFePO4 cells. Their capacity is considerably less, however accurate voltage measurement is possible. Also, they will hopefully last longer, being LiFePO4.

Dave

 

[novice]

Thank you, Dave!