Help with IR readings

[Mongoose]

So I wanted to check the IR on my batteries because there was a time I charged them all up and let them sit for about 3.5 weeks fully charged and I wanted to know if it damaged them.

What do you guys think of these numbers?

Every charge has been a balance charge and they have been put on storage time every single time before and after that 3.5 weeks.

These batteries are about a year old other than the last two. They are like 6 years old.

I used a Tenergy IR checker to check these and from what I have read the cheap versions usually show the first cell higher than the others which is what I have seen here.

I don’t see any puffing on any of these.

The 2S and 3S batteries run as a pair all the time but the 3S’s run deprecate when I run my Granite but I rotate them.

Lectron Pro 6S 5200mah 50C
8ohm
2ohm
2ohm
2ohm
2ohm
5ohm

Power Hobby 4S 5200mah 50C
8ohm
2ohm
2ohm
6ohm

Lectron Pro 2S 7600mah 75C (Green Stripe)
9ohm
5ohm

Lectron Pro 3S 7600mah 75C (Green Stripe)
5ohm
2ohm
4ohm

Lectron Pro 2S 7600mah 75C
9ohm
5ohm

Lectron Pro 3S 7600mah 75C
9ohm
2ohm
2ohm

Eflite 3S 1000mah 20C
13ohm
7ohm
7ohm

Kinexis 2S 1000mah 30C
2ohm
19ohm

 

[TraverseCity420]

13, 19, even the 9's are a little high

2-5 is pretty normal

 

[Yonic]

IR rating should be relative to the mah of the battery.

I've read somewhere that a rule of thumb is that a good IR is number close to or under 12000/mah. So for your 1000mah batteries 12 or under is good. but that 9ohm that you have on that 7600mah battery is really bad.

those Lectron doesn't look that good...
Was the Eflite 3S charged for that long as well? it is by far the best of the bunch.

 

[Yonic]

also important to note that IR changes greatly with temperature, so if you want to compare, first have them all rest in the same ambient temperature for a while.

 

[Mongoose]

13, 19, even the 9's are a little high

2-5 is pretty normal

Those are on the first cell which I would like to think it’s because of my cheap meter. It’s seems like a consistent pattern.

They have been sitting in storage mode for a while...maybe I will charge them, drain them and check them again.

Also, what’s funny about that Eflite is, and I didn’t realize this when I said 6 years before, but that battery is probably closer to 7 years old and hard telling how many times it had been stored fully charged because I bought this when I first got back into RC.

 

[Mongoose]

I've read somewhere that a rule of thumb is that a good IR is number close to or under 12000/mah. So for your 1000mah batteries 12 or under is good. but that 9ohm that you have on that 7600mah battery is really bad.

Can you elaborate on this please?

 

[DoNoHarm]

Remember, high IR doesn’t mean a bad thing necessarily. The “above 7 rule” is a lie. Hell, you can have a battery with every cell at 25, as long as they’re all between 24 and 27 than you’re in good shape. The only way a battery can be bad is the variation between the IR ratings. 5 may be considered “fine” but if all the other cells are between 1 and 3, your cell is prematurely dying before the other ones.

 

[Yonic]

I read that here, not sure about how legit it is.

 

[DoNoHarm]

All of it is a misconception. IR, c rating. All of it. Watch this video. It’s all completely wrong. All of it.

 

[DoNoHarm]

For the OP, your meter is malfunctioning. Can’t draw conclusions from any of your results.

 

[Cheapbastard]

I have never paid close attention to the IR readings unless I feel something is wrong with the pack whether the cells take forever to balance, the pack or one cell dies quickly, or the pack does not charge to capacity. For me when the cells get close to 20 the performance of the pack has usually diminished whether it's the run time or just the amount of punch the battery has. Whether this correlates to the iR being higher I can't say.

In the end don't take it to seriously just use it as tool to give you indication of why a pack or a cell may not be balancing, a pack might be dying a little more in use than usual just something that doesn't seem right in general.

 

[DoNoHarm]

I have never paid close attention to the IR readings unless I feel something is wrong with the pack whether the cells take forever to balance, the pack or one cell dies quickly, or the pack does not charge to capacity. For me when the cells get close to 20 the performance of the pack has usually diminished whether it's the run time or just the amount of punch the battery has. Whether this correlates to the iR being higher I can't say.

In the end don't take it to seriously just use it as tool to give you indication of why a pack or a cell may not be balancing, a pack might be dying a little more in use than usual just something that doesn't seem right in general.

Exactly what he said!!^

Actually here’s an example of a bad battery. I have 2 Traxxas 3s packs that I run in my e revo. One has always been run in the positive side. The IR was all 7. The ground side is the one dying now, just like everyone says. Readings were 8 8 and 13. Not surprising, was always struggling to bring that last cell up to voltage. I never really took it seriously, but yes, if you do not rotate batteries, the one towards the ground wire on the esc will wear out quicker. Lesson learned, rotate your packs people.

 

[Mongoose]

@Peeeenuuutt & @Cheapbastard thanks guys. I will watch it. Also, my IR meter is a cheap one but brand new. I just got it today BUT it just may be a crap IR meter.....

https://power.tenergy.com/tenergy-5...MIqI6Owp_J4AIVkEoNCh2A0QRTEAQYASABEgJ0MvD_BwE

 

[Cheapbastard]

@Peeeenuuutt & @Cheapbastard thanks guys. I will watch it. Also, my IR meter is a cheap one but brand new. I just got it today BUT it just may be a crap IR meter.....

https://power.tenergy.com/tenergy-5...MIqI6Owp_J4AIVkEoNCh2A0QRTEAQYASABEgJ0MvD_BwE

It's not crap it's the one I use whether it's entirely accurate can't say but it serves it purpose for my use. Don't expect accurate readings like the one in the above video it is what it is for it's price and to me is better than nothing. Like I said if you feel something is wrong with a cell or pack it can give you an indication albeit not entirely accurate idea of the problem might be and in which cell.

I will give an example of high IR and a 2s pack that will charge to 8.4v but die rather quickly and what one of the cells IR was. I would say it was extremely high whether accurate or not I would say the cell is bad.

 

[DoNoHarm]

Ok ok but his meter is definitely messed up lol. Can’t draw any conclusions from the OP’s meter, it’s flawed all over the place, unless somehow the first cell on all his packs is bad.

 

[Cheapbastard]

Ok ok but his meter is definitely messed up lol. Can’t draw any conclusions from the OP’s meter, it’s flawed all over the place, unless somehow the first cell on all his packs is bad.

Yeah I agree something doesn't seem right. But the only one that's really off is the Kinexsis 2s.

 

[slick2500]

For the OP, your meter is malfunctioning. Can’t draw conclusions from any of your results.

I have this same meter and my batteries were all over the place, one of my fairly new 2s mini lipos showed 125 ohms on one of the cells and 3 ohms on another, this battery charges and works just fine. I personally think that the IR meter in this is garbage.

 

[Cheapbastard]

I have this same meter and my batteries were all over the place, one of my fairly new 2s mini lipos showed 125 ohms on one of the cells and 3 ohms on another, this battery charges and works just fine. I personally think that the IR meter in this is garbage.

Tested all my lipos with it never seen one read 125ohms the readings maybe all over the place but never like that.

 

[Cheapbastard]

Again don't read a lot into a $14 to $15 lipo checker trust the one in your charger or spend the money for the one in the above video. If you expect this to be the that all be all than you will sadly be disappointed.

 

[Mongoose]

I haven’t seen any indication that I have any bad cells. They all balance and discharge evenly and still have plenty of power. Really the only reason I decided to check was from the fact they sat so long fully charged and I was curious to know if it caused any damage.

Now that you say you use this same meter @Cheapbastard, you were the one I found out about this meter from...I figured why not just check if it only cost $15 since I have wondered about my packs ever since I left them like that.

It’s gotta be faulty, maybe it isn’t very accurate, but I would think it would be inaccurate across all cells, not just the first cell on each pack showing so far from the others.

I’m not going to worry about it too much for now since the packs seem to be good. I do plan to get a better charger in the future so I will just be sure to make it one with a good IR meter.

I think I can still use these readings a basepoint to monitor the health of the packs from this point forward though so long as they check the same again. I will charge and discharge them and see how it reads and go from there.