After reading this forum and others on IR, I wanted to see what my LiPos measured. So, I purchased one of these meters because of its versatility, knowing it wouldn't be near as accurate as Wayne's meters. http://www.hobby-lobby.com/i_meter_7...34262_prd1.htm
I just received it and measured all my LiPos. I also realize the exact numbers don't mean much because it's the relationship of the numbers that count.
With that understanding here are some IR numbers (all in mohms) of individual cells (it doesn't measure total battery IR):
Two brand new (just received, never charged) 3S, Zippy 2200, 25C batteries from Hobby City. One reads 26, 27, 26. The other battery reads 23, 24, 23.
Three one-year old (about 15 cycles each) Turnigy, 2200, 3S, 25C batts read as follows:
33, 32, 33;
35, 32, 32;
37, 38, 33.
These readings came as no surprise in comparison to the two new batteries above.
I used to keep my batteries charged all the time, before I knew better. Here are some readings of those batteries:
A four-year old ABF 3S, 2200, 20C (about 20 cycles) reads: 90, 105, 95.
A three-year old Rhino, 3S, 1350, 25C (about 25 cycles): 96, 107, 104.
A two-year old HobbyZone 3S, 1300, 15C (about 10 cycles): 115, 57, 68.
Other similar 3S batteries had similar readings. The relationship of these readings come as no surprise given what has been said on these IR forums.
A two-year old ThunderPower 3S, 4200, 15C (about 2 cycles but kept charged for over a year): 64, 88, 66.
I find that my 4S batteries are holding up better. They have less cycles but I wonder if that's the only reason. I think I read that larger batteries hold up better. Some 4S readings:
My four-year old 4S HexTronix, 3250, 20C from Hobby City: 33, 32, 39, 38.
Two PolyQuest (several years old) 4S, 3300, 25C:
32, 30, 36, 38;
32, 34, 30, 32.
My two worst 4S batteries (Rhino, 3700, 20C) are only about two-years old and have only about five cycles on them. But again, they were kept fully charged for about one year:
137, 107, 95, 107.
40, 68, 93, 63.
Now I have a good idea what are my best and worst batteries. Okay, so what do I do with that info? I ask because my worst batteries still seem to work okay. Maybe not as long flight times but that's about all I can detect. I don't fly my batteries hard, maybe that's why I don't see much weakness. I'm sure not ready to cut off the leads and throw them away. I guess I just need to be aware of the weak ones and keep a keen eye on them when flying.
Any thoughts or observations?