InfidelCastro said:
Hello InfidelCastro,
OK, let me give you a quiz...
I have 8 CR123 cells that have the following open circuit voltages:
2.993
2.988
3.000
3.008
3.020
3.034
3.029
3.040
How would you rate them?
Tom
I had a nice long reply typed out, but IE crashed, and then the cable guy showed up, so I'll try this again. Here's the Cliff's Notes of my previously attempted post:
Assuming they are rested cells and not used recently, to me it would depend on the vintage and brand of the battery to me. Also, I would likely test fire two batteries of similar voltage and then take a reading after that. That will give you a good idea if the cells are matched and what their condition is.
For example most of the cheaper cells such as Titanium and Battery Station that I've seen come with a voltage around 3.1-3.05V to start with.
I received a 6P from B/S/T the other day. The batteries that came with it were Surefires dated 06/2015. They both tested at exactly 3.140V. This tells me they were probably used together and are likely the original batteries. It tells me that they may have been turned on once for a few seconds or not at all. It tells me they are close to new batteries.
Most brand new quality cells like Surefires, Duracells and Energizers come with a starting voltage of around 3.2-3.28V.
To me, what the ZTS tester says of the batteries makes little difference, because I judge batteries by what I'm going to run them in and not by overall capacity.
Now, I have three questions:
1. Is it true that the ZTS tester uses voltage reading to ascertain battery capacity?
2. Is it true that the ZTS is not designed for lithium batteries?
3. How would the ZTS predict a battery suddenly going bad any better than a multimeter? Regardless of whether it tests it under load for a couple seconds, I still don't see it.
If you're testing your cells immediately after putting a substantial load on them and take into consideration the brand of cell (if its performance is known), then I would agree that you'll have an indication of the condition of the cell, at least much more so than taking a straight out DMM voltage reading (which is your implication from your post seeing as you made reference to a slight load as a result of a voltage reading but not to applying any other additional or 'in use' loads). Still not as accurate or consistant as the ZTS, and no where near as fast.
You still didn't answer Tom's question, which would give me a great deal more info, but my guess is that you can't answer it with any degree of accuracy.
I just spent way too much time testing cells on the ZTS and a DMM and I don't want to waste but so much time here now, but for starters with your starting voltage: I tested 3 BS cells with a starting voltage of 3.23, 3.23 and 3.22. One tested out to 80% and the other two to 40%.
3 SFs were 3.08 (had been used for a few minutes), 3.12 and 3.15 (both new, but 3 years old) - all tested 100%.
1 used CR2 Duracell read 2.90 and tested 20% while a new BS read 3.08 and tested 20%. Kinda blows away your starting voltage info.
While using the cells (subjecting to a load) and then testing will give an indication, there are just too many variables for consistancy: How much of a load, for how long, and how long after the load is the voltage read?
1. My understanding is that it utilizes a formula to read voltage while applying a load to determine the cell capacity/condition.
2. The ZTS is very much designed for lithiums. The newest MBT-1 was designed for and at the request of the CPF community. It added a nipple to test 1.5V lithium primaries (AA & AAA) and a nipple for lithium-Ion (RCR123A, 18500, 17650, 18650). It did and stills does lithium coin cells and CR123, CR2 and CRV3.
3. What do you mean by, "going bad?" If you mean, becoming exhausted from use, it only gives you a good indication how close to or how far from its original capacity the cell is. From there, you have to have some knowledge of how long a full cell will last in whatever you're using it in and how long you have been using it to know when it will crap out. If your cells are new, it can tell you if you're starting out with a crappy cell or one that's up to standards.
It's been my experience that a lithium primary will last longer and run flatter, but when it goes, it goes, usually with very little or no warning.
ZTS tests 1000s of cells and 100s of different brands and they come up with a "standard" to test to. While I'm sure that it's not perfect and subject to some exceptions, it's a damn site more accurate and USEFUL than a straight DMM reading.
I'm very pleased with my purchase and I'm proud to say that it was a Father's Day gift from my daughter - that's how long I've been waiting for mine.
