Turnigy LiPo quality?

[Jeremy Harris]

The first batch of LiPo batteries I bought were 5Ah, 20C Zippys. They were excellent, all arrived with cell voltages matched to within about 10mV and they have stayed in balance extremely well in use.

The next batch were Turnigy 5Ah, 20C and these weren't so well balanced when they arrived; cell voltages were as much as half a volt out across the pack, with one pack having a cell down at 2.5V. Nevertheless, I carefully balance charged them, one cell at a time on a single cell charger, and they seem to now be staying pretty much in balance and delivering their rated capacity.

Yesterday I received another batch of Turnigys, 12off 5Ah 20C ones. Out of the twelve packs, three have major problems. One pack has a total voltage of 1.45V(WTF!!!), two packs have cells that are down at 2V or so. Despite having bought them from the German branch of Hobby King, apparently the bastards want me to ship them to bloody China for replacement under warranty. My guess is that the shipping cost will exceed the value of the batteries, making the warranty useless. If they allowed me to ship them back to Germany (as required under EU consumer law), then it'd be OK, as shipping to Germany from here is relatively cheap.

Given that it's not worth sending these packs back, I'm going to try and see if I can recover them. The two with low cells look to be recovering OK, hopefully they will be as good as the other packs. The pack with five cells that were down at a fraction of a volt is, oddly enough, charging OK and all five cells seem to be coming up in reasonable balance.

Am I alone in getting crap batteries from HK or is this sort of 25% failure rate normal? I know they're cheap, but frankly it may not be worth dealing with them if the quality is persistently as poor as this.

Jeremy

 

[Ykick]

I haven't bought any in a while but my experience is almost reverse. My 1st order of 13 packs about a year ago arrived with one very dead cell in one 5S pack and a weak/low one in each of 2 other packs. Many cycles later the 2qty funky ones do get out of balance but at a fairly slow rate (month use) and I simply watch 'em closely. These were 20C Turnigy I believe.

The absolute best "quality" I ever got from HK has been those 6S 15C Zippys. Bought 4qty and they all started out a winner - even after nearly 9 months running 1P on 30A controller they're still perfectly balanced showing 5-10MV difference. Other than initial assembly I haven't needed to balanced these yet.

Perhaps contact HK and ask what they can do to help soften the sting of the bad ones? 25% seems like a high bad count...

 

[johnrobholmes]

Zippys have been the most consistent for me. Turnigy seems hit and miss.

 

[Jeremy Harris]

Thanks, I've contacted HK and got an RMA number, just in case, as they only allow returns within 7 days. If I don't get a return number now I'll be cutting it fine if I decide to send them back next week.

I'm reasonably happy to post the duff packs back to Germany, but having checked, sending them to China instead will be around $45. It only cost $16 to get all 12 shipped from Germany. I guess sending three packs back is cheaper than buying three new ones, but it's pretty irritating to have to go through all the hassle of returning 25% of the order, and incurring an extra 10% of the price in additional shipping charges, just because their quality control sucks.

I think I may stick to the Zippy packs in future, given that it looks as if they might be consistently a bit better.

Jeremy

 

[johnrobholmes]

The zippy "flightmax" has not been well to me, going through my piles. It has an even worse track record than the turnigy packs I have bought. Looks like plain zippy packs aren't on HK site now, so I would say the turnigy may be the best bet over the long run. Almost like playing craps sometimes though.

 

[liveforphysics]

I've got a strong hunch as to the source of the problem.

Keep in mind this is totally unfounded, just based on will-ass-guessing.

I don't think that a cell factory would choose to make 20C cells after they have the formulas/tools/methods to produce 30-40c cells that use the same amount of materials to produce.

Again, just as a totally wild-ass-guess, we could draw some wild-ass-conclusions.

Cells sold as 20C cells could be the rejects from the 30-40C production runs? Cells sold as 20C could be older cells from generation 2 lipo formulas/construction methods rather than the modern 3rd generation stuff?


Being interested mainly in high performance, I've tended to only buy whatever the highest C-rates they happen to offer at the time. I've never had a bad cell yet, or a pack that had an issue (unless it was something I caused).

 

[Jeremy Harris]

Thanks, John, maybe I'll stick with the Turnigys then, although the good Zippy packs I have are all badged "Flightmax".

The two packs with one low cell look as if they may be OK, the pack that was down to 1.45V has puffed every cell when I tried to charge it at a low rate (around 1A), so is definitely dead. It might be worth sending back just the one totally the dead pack and risking it with the other two, given the difference in shipping cost. Looks like I'll need to wait a while now before being able to test the controller and dyno, which is a bit of a bugger, unless I bodge up a test pack from the good cells I have.

Interesting theory, LFP, might be some truth in it, too. It may well be better in the long run to buy the higher C rate cells just to be sure of getting fewer duds. If I have to send all three duff packs back, then the extra return shipping cost is not far off the difference I'd have had to pay to get the 30 or 40C cells in the first place.............

Jeremy

 

[El_Steak]

Damn, I just ordered 2 of these last night. Maybe I should change my order for the Zippy's before it ships...

 

[johnrobholmes]

I just ordered 6x turnigy, if it makes you feel any better :lol:

 

[EVDragRacer]

As most all know I am building a huge pack for these Turnigy cells. I have tested over 20 packs already and all have been within the numbers. I am using an Icharger/balancer. I have 40 more to test, i will keep you updated.

 

[Bazaki]

I've bought several flightmax 138mah for a mini helicopter. I think I got 40mah out of them, so for my ebike and e-outboard I've decided to go for turnigy, and all 12 x 6s 5ah are after 1 year still perfect.

 

[Jeremy Harris]

It looks like I've just been unlucky, then.

The bottom line seems to be that I've definitely got one totally dead pack, with every cell dead in it, and two packs that might be OK with some TLC to get them balanced. Maybe I'll just send the totally dead pack back and hope that the replacement they send (assuming the do) is OK.

I think I'll take LFPs advice and only go for the higher C rate packs in future, in the hope that they'll be a bit better quality.

Jeremy

 

[full-throttle]

Same here Jeremy,

Received 20 packs of 4S1P 5Ah 25C Turnigy from AUS warehouse this week:
3 cells dead (0V)
1 cell 2.69V
the rest are 2 .83 +/- 0.3V
shipping back to China instead of Aus, WTF??

Think Hyena had similar experience recently..

 

[liveforphysics]

The bottom line seems to be that I've definitely got one totally dead pack, with every cell dead in it,

Statistically, that seems so odd. Almost has to be the result of something that was not a cell problem at all, but a pack construction error/contamination that resulted in the discharge terminals slowly being discharged across some high resistance over time.

I'm sorry you got a bad group of packs my friend.

 

[knoxie]

Hi Jeremy

Sorry to hear that you have had problems with the Turnigy packs, I got 4 x Turnigy packs direct from HK in june they have been rock solid, they were 6s packs 25C no issues at all, I havent ordered from Germany yet, maybe they got bulk shipped from HK direct and stood in German customs or were held too long at too low SOC? just a thought? might be interesting to see if there is a difference between the packs people have been buying direct from the PRC and their warehouses located elsewhere?

Good luck in getting them sorted

Knoxie

 

[johnrobholmes]

I thought the whole reason of the new warehouses was for quicker shipping and returns. I would be making a stink about having to return it to china, especially since it wasn't bought from there.

 

[MitchJi]

Hi Jeremy,

Interesting theory, LFP, might be some truth in it, too. It may well be better in the long run to buy the higher C rate cells just to be sure of getting fewer duds. If I have to send all three duff packs back, then the extra return shipping cost is not far off the difference I'd have had to pay to get the 30 or 40C cells in the first place.............

The problem is you can't be sure. You might just end up with more expensive duds .

 

[dogman dan]

It sure seems to be hit or miss. I have some turnigy 30c and some zippy 20c in 5s. Both orders arrived fine in general. One zippy pack balanced poor for 2 cycles then perked up and acts normal now. But two 4s turnigy packs I bought both have minor puffing, though they seem ok for the 20 cycles or so I have used them. I charge em outside for sure though!

Soooo, pretty much 100% OK for both turnigy and zippy 5s, and 100% defect for turnigy 4s. Theres' a pretty random pattern. What difference does the 5s vs 4s make with the same 30c cells? It's a trip to the casino. I look at it like buying lumber for building an entire house, Just figure on 20% of it being unusable, and calcuate that into your budget. Consider any less to be a freebie like winning at blackjack.

 

[Jeremy Harris]

It's a trip to the casino. I look at it like buying lumber for building an entire house, Just figure on 20% of it being unusable, and calcuate that into your budget. Consider any less to be a freebie like winning at blackjack.

I'm coming to the same conclusion, best to add 20% to the order and to the cost when comparing HK with other suppliers. If I get more than 80% usable packs then I'm sure I'll find a use for them

I might be worth making this lottery aspect of buying LiPo from HK known to the new folks who pop on here, as they may be more than slightly miffed at buying the odd duff pack for a small project if they've ordered just enough packs to do the job. For a lot of us here this doesn't matter, as some of us just keep accumulating batteries like it's some sort of collecting addiction..........................

Jeremy

 

[Ykick]

"collecting addiction..." I like that!

I thought most of us have been saying to buy extra for spares because of expected failure? But it doesn't hurt to repeat often as discussions of buying cells appear.

I'm getting geared up for soldering this stuff with the hope of eventually replacing individual bad cells. Overall I'm pretty happy with what I've got from HK and I must've gotten lucky with those 15C Zippy FlightMax packs because they're the most balanced and seemingly stable of all my Lipo cells. And, I didn't buy them at the same time either - I started with 2 packs for a spare backpack battery. Couple months later added another 6S pair and they were just as solid performing as the 1st batch.

 

[MitchJi]

Hi,

Might be a good reason to buy the Nano packs.

Anyone ever get a bad Nano pack?

 

[gtadmin]

At least I'm not alone!
From my build log ....

Received 12 of these yesterday (Tues 5th Jan 2011).
Voltages are as follows:
Cell1 Cell2 Cell3
0.005 0.696 0.701 ***** 1.406Vt - pack noticeably puffed
2.697 3.693 3.541 ****
3.857 3.739 3.861 **
3.730 3.857 3.852 **
3.809 3.859 3.857 *
3.853 3.859 3.855
3.853 3.859 3.844
3.858 3.859 3.846
3.867 3.865 3.864
3.859 3.861 3.852
3.858 3.863 3.859
3.858 3.861 3.857

***** rooted
cell delta legend **** ~1V (0.996mV) ** >100mV * >50mV
RMA 25527-1871804 entered for the stuffed one, return address supplied after entering RMA request is China, even though the popup at the bottom of the page informs the customer that this is NOT correct. I'll wait until I get an Oz address then ship it there. Previous batteries shipped from China were excellent (2off 8S 5800mAh Long packs, with all cells within 10mV).


So much for quality control At the very least, I have the address of the sender, and I'll send the very rooted one back to that address and let them dispose of it The one with a cell at 2.697V I am balance charging to storage voltage at 0.1A and we'll see how it goes

These are 25C cells. I have a feeling that this mostly applies to cells sourced from the "other" warehouses, not China? The three other packs have come up OK with a slow ..... balance charge to storage voltage (not load tested yet) but I'm not game to try and charge the first one!

Cheers,
GT

 

[Jeremy Harris]

HK customer support have replied to my email about the problem and asked me to take photos of the defective pack, showing cell voltages, all connecting leads in place, packaging notes etc. The suggestion is that they may not need me to post the pack back to them, their warranty people will look at the photos and may issue me with a credit note.

As soon as I hear back from them I'll post an update, but I'm hopeful that this may mean I don't have to ship the duff pack back to China. The two packs with low cells are fine now, they too a fair bit of balancing, but look to be as good as the other packs. The only annoying aspect is that I wanted all 12 packs to build a 15S, 4P pack, so I'll have to go with just 15S 3P until the replacement arrives.

Jeremy

 

[dogman dan]

That would be a big improvement, if you could simply take a pic of a defect pack showing a puffy, including a bar code and get a new one sent, or at least your account credited for the next purchase. they could track the bar code and never credit a pack twice.

the bar code would have to be done so the thing couldn't be moved to an old pack, of course.

 

[gtadmin]

HK customer support have replied to my email about the problem and asked me to take photos of the defective pack, showing cell voltages, all connecting leads in place, packaging notes etc. The suggestion is that they may not need me to post the pack back to them, their warranty people will look at the photos and may issue me with a credit note.

As soon as I hear back from them I'll post an update, but I'm hopeful that this may mean I don't have to ship the duff pack back to China. The two packs with low cells are fine now, they too a fair bit of balancing, but look to be as good as the other packs. The only annoying aspect is that I wanted all 12 packs to build a 15S, 4P pack, so I'll have to go with just 15S 3P until the replacement arrives.

Jeremy

Sounds promising Jeremy. Any chance you would like to share the email you sent? (You have a more subtle use of the English language than me - mine is more akin to a sledgehammer )