450 Battery Problems...

Rob Lancaster

Rob Lancaster

Active Member
Hi all!
Hey can someone tell me why my 2800mAh 30c 3 cell lypos seem to have a charge but at throttle up all 4 of my packs just fade big time and the 450 chopper doesn't leave the ground.

They only have less than 50 flights on them...
They were stored at the storage voltage for more than 5 years but seem to charge; all though not balanced as good as they should be, but close.

What do you guy think? Are they just old?
I don't want to throw them away if they can be saved...

Hey Toni, I got the head dialed in great and was flying her in a 25 MPH cross winds today. Ahhh,,, collective pitch, you gadah love it!! Oh when the wind hits the tail rotor; that's music to my ears folks!!
Thanks for the advice,
Rob... IMG_1509.JPG
 
Tony

Tony

Staff member
If the batteries sat for 5 years, it is likely they are just worn. I would purchase a single battery and see how it compares. It could also be an ESC or motor issue as well, but I would start with the battery first.
 
Rob Lancaster

Rob Lancaster

Active Member
Thanks Tony, I had a feeling you were going to say that. Here's the trippy part.
I forgot to mention that I do have two 2200 20c 3 cell packs that do fly the aircraft for about 7 minutes. That's what I used today in the wind. Get this,, their older, with more time on them than the 4 packs that went south. Hummmm,,, I wonder if some how the internal resistance (IR) built up in storage?..... I know there's power in the packs because it took a while to discharge two of the 4 packs to 3.2 volts and the heat sink on the charger/discharger is hot. It really seems the power is in there; but it is having a hell of a time getting out... Just a theory,, and if that's the case, I think their toast...
 
Geena

Geena

Staff member
Did you leave them in storage for those five years at full charge, or did you put them on storage charge? Storing lipo batteries at full charge, is one of the worst things for them. It does sound like those four packs are done though.
 
murankar

murankar

Staff member
Sounds like those packs are done if that's the case. There are many factors that play into pack degradation.

If you have a charger that does pack analyzing then try that. The only charger that I know of to do this is the powerlab PL series chargers.
 
Rob Lancaster

Rob Lancaster

Active Member
murankar said:
Sounds like those packs are done if that's the case. There are many factors that play into pack degradation.

If you have a charger that does pack analyzing then try that. The only charger that I know of to do this is the powerlab PL series chargers.
Click to expand...
Geena said:
Did you leave them in storage for those five years at full charge, or did you put them on storage charge? Storing lipo batteries at full charge, is one of the worst things for them. It does sound like those four packs are done though.
Click to expand...
Geena said:
Did you leave them in storage for those five years at full charge, or did you put them on storage charge? Storing lipo batteries at full charge, is one of the worst things for them. It does sound like those four packs are done though.
Click to expand...
 
Rob Lancaster

Rob Lancaster

Active Member
Geena said:
Did you leave them in storage for those five years at full charge, or did you put them on storage charge? Storing lipo batteries at full charge, is one of the worst things for them. It does sound like those four packs are done though.
Click to expand...

Nope, I stored them at 3.8 volts...
 
Tony

Tony

Staff member
Sounds like degradation of the pack to me if you have another pack, even 20c that is doing better. Check the IR of each of the cells if your charger can do that and post the numbers here.
 
Rob Lancaster

Rob Lancaster

Active Member
murankar said:
Sounds like those packs are done if that's the case. There are many factors that play into pack degradation.

If you have a charger that does pack analyzing then try that. The only charger that I know of to do this is the powerlab PL series chargers.
Click to expand...

Nope, just got 4 of these cheap'0 chargers shown in the picture. Hey everyone, I came across an excellent article that explains just how lypos work. A Guide to Understanding LiPo Batteries It also talks about (IR) internal resistance and what causes it. I'll just bet that's what happened to my 4 cheapo packs; Li20... It's a form of lithium corrosion that builds up on the cathodes and anodes of the battery's internal connections. When this happens, the cells won't take and or hold a charge and you now have what we say in Hawaii; a fishing weight, ha! Have a look at the article, it's an eye opener in many ways. I think what defines a cheapo battery is one that's made from inferior quality materials, thus the cheaper price. A battery made of higher quality anodes and cathodes and just plain ole better quality chemistry, is a battery that is going to store and perform better... Thanks everyone for your thoughts, Rob... 003.JPG
 
Rob Lancaster

Rob Lancaster

Active Member
Tony said:
Sounds like degradation of the pack to me if you have another pack, even 20c that is doing better. Check the IR of each of the cells if your charger can do that and post the numbers here.
Click to expand...
I wish I could measure the (IR) of each cell, nope not my chargers... Hey does the DYNAMITE PASSPORT DUO 400 WATT charger measure the internal resistance?
 
Smoggie

Smoggie

Well-Known Member
Icharger or Powerlab chargers do IR checking, or you can buy stand alone battery checkers that do it.

If your batteries are 5 years old then that's the problem for sure. Even when properly stored 5 years is a long time and it's a lottery (with bad odds) as to if they will be usable after that time. Biut don't throw them in the trash just yet, if they aren't puffed you can use older 'tired' batteries as a power source for field charging. Just connect a few of them in parallel and power your charger of them, the demand for charging is much lower so even old tired batteries do ok in that duty.
 
Rob Lancaster

Rob Lancaster

Active Member
Smoggie said:
Icharger or Powerlab chargers do IR checking, or you can buy stand alone battery checkers that do it.

If your batteries are 5 years old then that's the problem for sure. Even when properly stored 5 years is a long time and it's a lottery (with bad odds) as to if they will be usable after that time. Biut don't throw them in the trash just yet, if they aren't puffed you can use older 'tired' batteries as a power source for field charging. Just connect a few of them in parallel and power your charger of them, the demand for charging is much lower so even old tired batteries do ok in that duty.
Click to expand...

Defiantly thanks for the charger tips! I really want to be able to read the IR if possible...
 
Smoggie

Smoggie

Well-Known Member
Rob Lancaster said:
Hey while were on the subject; what is the best size battery for a 450 heli anyway?
Click to expand...

Traditional 450 helis (that spin 325mm blades) are usually designed around a 3S 2200mAh battery. Recent 450 helis have grown to 360mm blade size and they usually use 6S batteries in the 1200mAh to 1400mAh range (and different motors to suit).
Go for at 30C, the higher the better
 
Smoggie

Smoggie

Well-Known Member
Rob Lancaster said:
What is a stand alone IR checker and where do I find them?
Click to expand...

The best one is called the 'Wayne Giles ESR meter' it's the gold standard for IR measurement and the one all others are bench marked against, but probably a bit OTT for most users. At the more budget end of the range Hobbyking do a couple of battery testers that have IR functionality... let me know if you need a link.

On the subject of Hobbyking; they do the 'Reaktor' range of chargers which are copies of the iCharger and have the same IR measuring feature as the iCharger, but at a lower price.
 
Rob Lancaster

Rob Lancaster

Active Member
Smoggie said:
The best one is called the 'Wayne Giles ESR meter' it's the gold standard for IR measurement and the one all others are bench marked against, but probably a bit OTT for most users. At the more budget end of the range Hobbyking do a couple of battery testers that have IR functionality... let me know if you need a link.

On the subject of Hobbyking; they do the 'Reaktor' range of chargers which are copies of the iCharger and have the same IR measuring feature as the iCharger, but at a lower price.
Click to expand...

Yes please, I'd love some links to learn what it's all about, thanks,
Rob...
 
Rob Lancaster

Rob Lancaster

Active Member
Smoggie said:
This is a 'stand alone' multi function tester from Hobbyking that does battery IR among other things: Turnigy™ 7in1 Mega Meter Battery Checker/Watt Meter/Servo Tester

The Wayne Giles ESR meter: Universal ESR Analysis Meter - ProgressiveRC

And the cheapest of the Turnigy 'Reaktor' chargers that have IR measuring capability:
Turnigy Reaktor 250W 10A 1-6S Balance Charger
Click to expand...

Sweet!! Thanks again! And I wonder what the IR is for my 4 dead cells? I'm going to save them and find out...
 
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