Swollen or not swollen lipo, what to do?

[Stratifier]

Hi,
Just noticed that one of my (brand new) lipos is slightly swollen. Not much but I have no clue of what is acceptable and what is not?
Pictures:
View attachment 21554
View attachment 21554
View attachment 21556
View attachment 21557

It's not completely rounded, and located on the top part only, but you can notice that it's definitely not flat. I've got 2 others that are dead flat.

 

[Stratifier]

Any Idea?

 

[Maverick]

Any Idea?

You should post pictures of the swollen one and non-swollen lipo side by side for comparison...

 

[Stratifier]

I doubt you can see it as it is not very obvious.I thought that the ruler speaks for itself. It should touch both of the angles and it clearly doesn't. there's maybe 4mm space where you should have zero.
I will try anyway to take these pictures you want.

 

[Maverick]

I doubt you can see it as it is not very obvious.I thought that the ruler speaks for itself. It should touch both of the angles and it clearly doesn't. there's maybe 4mm space where you should have zero.
I will try anyway to take these pictures you want.

Did you over discharge it...?

 

[Av8Chuck]

I think Bart started a good thread about batteries that you should check out. If I remember correctly there was a lot of discussion about proper charging, internal resistance and testing etc..

Giving online advice about how to make a MR more stable is one thing, giving advice regarding battery health is something I'm rather reluctant to do because the well intended consequences of that advice can result in really bad things happening. From the pictures doesn't look that "puffy" but the other battery thread used more technical terms to help you get a better understanding of the status of your battery.

Let heat be your guide, is it hot after using or charging it? After balance charge what percentage does it get to? How close are the individual cell? Is that a 6S?

 

[Maverick]

I think Bart started a good thread about batteries that you should check out. If I remember correctly there was a lot of discussion about proper charging, internal resistance and testing etc..

Giving online advice about how to make a MR more stable is one thing, giving advice regarding battery health is something I'm rather reluctant to do because the well intended consequences of that advice can result in really bad things happening. From the pictures doesn't look that "puffy" but the other battery thread used more technical terms to help you get a better understanding of the status of your battery.

Let heat be your guide, is it hot after using or charging it? After balance charge what percentage does it get to? How close are the individual cell? Is that a 6S?

+1...

 

[Stratifier]

Thanks, I'm going to check this thread. @Maverick: I didn't overdischarged it, I charged it only one time, and never used so far. [MENTION=292]Av8Chuck[/MENTION]: It was not hot after charging.
I was watching the charge of the 3, and stopped it at 98%, The charge this morning after 4 days is still 97% at 24.98V, from 4.157V to 4.173V for the 6 cells.

As it is new, I think the dealer should replace it anyway, I don't feel safe with it.

Thanks.
S

 

[Rotorfreek]

I see that it's slightly rounded, but is it firm or soft, like it's air or solid? Before they are shrink wrapped, they are wrapped long ways with a fabric core tape - which can stop batteries from being perfectly flat on every side.

Sent by my thumb, a trusty slave to my crazy mind. The above is the ramblings of a lunatic, and should be treated as such. Terms and conditions apply.

 

[Benjamin Kenobi]

It's probably okay, just a manufacturing thing. Does your charger do internal resistance (IR) monitoring? That's the best way to check the health of a lipo.

 

[Stratifier]

[MENTION=4382]Rotorfreak[/MENTION]: It's solid, no air apparently.
@Ben: I don't know. I should have a look at the manual , The charger is a Cellpro Powerlab 6.
Spoke to the supplier and they're ok to have it back, so I'm quite happy. will have a look anyway.

 

[Amerly]

Pretty much all said already... One last thing don't store them charged for to long (the less the better)... Target 3.7v to 3.8v per cell for that purpose... I discharge them at the end of the day if I could not fly them... Don't go to much under 3.6V under load when flying... No puffy (gas) on the touch is good for external layers but you could have a bad one (puffed) internally... Internal resistance of individual cells (on your charger) is the way to go... Tattu are great, keep us posted with your final diagnostic...

Are theses 16Ah or 22 Ah ?

My new 16Ah's are all close to 1 mΩ on all 6 cells (reading from ICharger 406 Duo)

 

[RobBurn]

Return it. Also you should not have a charged lipo more than a day. The real key is to the temp , if your in hot climate like over 80 I'd do a storage charge the same day. You can do as you wish but it's all risk related.

 

[smackenzie]

I've got one too - its a 4S 4000 mAH Century pack. Probably about 20 total cycles, but over a year old so it's not returnable. Up to the last flight, I've only discharged it to about 50% (the charge puts 1700-2000 mAH back into the battery). This last flight I adjusted the cutoffs down and flew it down to 25% (took 3002 mAH). Immediately after flight it was slightly warm, and puffy, both top and bottom, whereas before the flight it was flat both sides. It's soft puffy, like there is air between the plastic conformal wrap and the plastic battery cage. Pressing down (oh maybe 2 mm) through the soft puff the plastic battery cage feels flat.

Just wondering whether I need to toss it, or burp it?

 

[Bartman]

It's probably okay, just a manufacturing thing. Does your charger do internal resistance (IR) monitoring? That's the best way to check the health of a lipo.

i second the use of internal resistance to assess overall battery health. a little puffing ought to be your indication to look at internal resistance. if one or more cells have higher IR than the rest then the pack should be returned. if they're all 2 or 3 then i'd keep flying it while keeping a close eye on it over the next few charge cycles. if it charges fine and the IR doesn't creep up then you're good.