Duratrax Onyx 3S 5400 50C Puff Daddy ... tough luck, kid.

[Halifax]

Hi
Onyx battery at left. Powerhobby cell of same age and use at R.

Gents,
Picked up a pair of Onyx 3S 5400mAh 50C LiPo batteries when I bought my Nero from Tower. Over the course of about 10 cycles, they became swollen to the point where they are a tight fit in the Nero's belly holders. Always charged < 1C. Never had to add more than 2400mAh back into them. I pretty much run in well-mowed hayfields where my dogs can chase the truck.

Called Duratrax/Hobbico tech support to tell my story. I was told that there is no warranty, or more precisely, "essentially, the warranty ends the first time you plug it in to your charger." I told him that this made no sense, that there is essentially no warranty. He agreed.

Never again.

Onyx puffers.

 

[Kauaiguy]

Did you measure your battery temps during your first run,where you using the larger pinion?When batterys puff the usual factor is taking to many amps out of the battery than it was designed for.Battery temps over 125f will quickly lead to puffing.You need higher C value in your batteries,many battery companys lie on performance.

 

[Halifax]

Hi K,
No, I did not measure battery temp. Do you use a simple IR temp gun? I figured Onyx 50C would be fine as Tower sold it as a companion item. Given what I have learned from browsing the web, the Onyx batteries are quite prone to this failure. Too bad Hobbico does not stand behind their product, especially given the cost of these batteries.

 

[Kauaiguy]

Hi K,
No, I did not measure battery temp. Do you use a simple IR temp gun? I figured Onyx 50C would be fine as Tower sold it as a companion item. Given what I have learned from browsing the web, the Onyx batteries are quite prone to this failure. Too bad Hobbico does not stand behind their product, especially given the cost of these batteries.

I think they sell those for newbie to buy,so they can buy again when they fail.I use a simple temp gun on my batterys to monitor temps ,if they get hot ,need to reduce pinion size to reduce amp load,also running the battery till lvc causes extra heat,if you stop at 3.6v per cell it will be cooler!

 

[Halifax]

Excellent. Thanks for the advice. Will put it to use tomorrow!

 

[lonee]

I used jeti telemetry to check my amps while driving. After I checked that I am on a sure side, I unmounted it again.
I most using SLS LiPo but i don't know if can get them outside Germay.
I also use 3s LiPo from a german Conrad electronic, but i think the just rebranded and i don't know what is really inside.
I use them in a Nero BR...

Regards,
lonee

 

[mrfurious40k]

I have 2 sets of those packs for my Nero. I had one pack puff after a run. It was extremely hot, way below the low voltage cutoff level and much thicker than its twin. Any pack that you run in grass, even well mowed, will take a beating. Grass is horrible on RC cars.

Anyway, my pack returned to its original size and I haven't had another problem. The way I avoid the issue of overheating and running the pack too low is by installing low voltage alarms on both of my packs. I set them for 3.8v. When they start to alarm I know I'm pushing the packs too hard. I let them rest a bit and the voltage rises above my threshold so I can run some more. This allows me to monitor my packs in real time and I haven't had one puff it even get warm since I started using the voltage alarms.

https://www.amazon.com/gp/aw/d/B018...0_FMwebp_QL65&keywords=lipo+low+voltage+alarm

I'm satisfied with my Onyx packs but I have a set of SMC 5600mah that are much better and cost less. I'll be buying all SMC packs in the future.


http://www.smc-racing.net/

 

[Steve B]

I have 2 sets of those packs for my Nero. I had one pack puff after a run. It was extremely hot, way below the low voltage cutoff level and much thicker than its twin. Any pack that you run in grass, even well mowed, will take a beating. Grass is horrible on RC cars.

Anyway, my pack returned to its original size and I haven't had another problem. The way I avoid the issue of overheating and running the pack too low is by installing low voltage alarms on both of my packs. I set them for 3.8v. When they start to alarm I know I'm pushing the packs too hard. I let them rest a bit and the voltage rises above my threshold so I can run some more. This allows me to monitor my packs in real time and I haven't had one puff it even get warm since I started using the voltage alarms.

https://www.amazon.com/gp/aw/d/B018...0_FMwebp_QL65&keywords=lipo+low+voltage+alarm

I'm satisfied with my Onyx packs but I have a set of SMC 5600mah that are much better and cost less. I'll be buying all SMC packs in the future.


http://www.smc-racing.net/

The same sort of thing happened to me. I'm a newbie in the RC world and drove my Nero for the first time at a park with nothing but grass. One of the four onyx batteries puffed a little after the first run. When it cooled down the battery looked just about normal. My dilemma since I'm new in this, do I trust this battery again or should I toss it? I'm going to avoid driving on grass from now on. It was a pretty thick cut of grass too.