This is a little scary...
 

Saw this on the HobbyKing blog while browsing around:

"New B-Grade LiPo.
Same quality and reliability as eBay packs.
Price: Dirt Cheap
Cycle Life: 50+ only
Good for low discharge testing and not-so-critical flights."

They say good for low-discharge testing, and then slap a big 40C rating on it. You know there will be plenty of people who won't even read the description. Same quality and reliability as Ebay packs is NOT a selling point IMO! I'm already starting to smell scorched electronics and venting Lithium gasses.

http://i47.photobucket.com/albums/f1...9201112818.jpg

Suprised it does not have flames on the sticker... Like those D grade packs brand P sells...

wow thats crazy!

Folks new to the hobby and dumbasses who refuse to do some reseach will but the hell out of them. MA finially has some real competion !

where do I sign up?!?!
Will they start my car up?!

Oooo! Check out the new self-powered rocket motor ignitors! :lol:

Are the "not so critical flights" what happens when you fling it off your charging station as it bursts into flames?

If the battery dies you lose control and crash. Which to me says it's critical to have a good battery EVERY flight.

I could understand marketing these as Tx/Rx packs, but then they put the 40C rating on the label which totally contradicts the "good for low discharge testing" statement.

Well ever since MA introduced 150c lipos, 40c IS low discharge :lol:

I am just wondering when MA are going to bring out a lipo that you can use to power a charger. Then you can use that lipo to charge itself. A self charging lipo. It will be configured in series to power the charger and also in parallel so that the really good balancer circuit in the hyperion does not need to be used. Cause parallel charging is the way to go. And 500 bucks would be a steal for a self charging lipo.

At least they are honest about what they are selling instead of trying to put some rediculous rating on them and up the price..

I applaud them for just telling the truth.

True! But the buyer should be educated in what to look for when they start to give up.

There's all kinds of crooked things going on in the battery industry.

I recently purchased 3 protected 3000mah 18650 cells for a flashlight that I bought.

The flashlight would only shine for a minute or two before the cells hit their built in low voltage cutoff.

Discharge testing at 1 amp only showed 150 - 200mah of capacity.

Protected cells that were counterfeit. My guess is "fresh" out of the recycle bin.

Alot can be hidden under shrink and end caps.

Check this out.

Looks good so far.

<a href="http://s160.photobucket.com/albums/t187/sikeston34m/?action=view&amp;current=DSC08523.jpg" target="_blank"><img src="http://i160.photobucket.com/albums/t187/sikeston34m/DSC08523.jpg" border="0" alt="Photobucket"></a>

Under the cap, notice the multiple weld marks and the scrapes to remove them, before the new cap was added.

<a href="http://s160.photobucket.com/albums/t187/sikeston34m/?action=view&amp;current=DSC08525.jpg" target="_blank"><img src="http://i160.photobucket.com/albums/t187/sikeston34m/DSC08525.jpg" border="0" alt="Photobucket"></a>

Yes, on the other end too. There's even some rust.

<a href="http://s160.photobucket.com/albums/t187/sikeston34m/?action=view&amp;current=DSC08527.jpg" target="_blank"><img src="http://i160.photobucket.com/albums/t187/sikeston34m/DSC08527.jpg" border="0" alt="Photobucket"></a>

Notice the dents on the naked cells. It's like they were all dumped together in some large bin. This doesn't happen on the production line.

Also note, different lot dates on the 3 cells. Definately not the same run. Probably not even the same brand.

<a href="http://s160.photobucket.com/albums/t187/sikeston34m/?action=view&amp;current=DSC08529.jpg" target="_blank"><img src="http://i160.photobucket.com/albums/t187/sikeston34m/DSC08529.jpg" border="0" alt="Photobucket"></a>

Who's going to bring them to justice though?

If you can find them......maybe you can hire the A-team:lol:

That sucks dude! I bought some lithium camera batteries that were suppose to be 1400mah. After dis-assembly, I noticed they were only half the capacity. They were suppose to parallel 2 pairs of 700mah batteries, but only used 2 cells instead of 4...

I just jump started my car with a 4s 5kmah this morning:sleep:


the batt was hot enough to melt snow....

So, 32.1*F?

*failed at thinking of a smart___ comment*


It was 90*f+ after 1-2min...

You know, I was thinking of this exact thing yesterday...

I was wondering what they do with all the packs don't somehow don't manage to even pass their quality control.

I guess now they're gonna sell em.

how the hell did you jump your car with 4s 5ks?

Shoveling dirt for your dad, with your dad or on your dad?

:rofl:
All of the above?

I can agree with that for the "B-grade" rating, but look at the C-rating. They say they are for low discharge testing, and then rate the pack at 40C? Doesn't make any sense to me. IMO low discharge is 5-10C (and even that, if truly a constant current draw, can be tough on packs)

you strip the wires and hook the jumper cables up...

1-2 min later you turn the key...

rocket science....

:na:

Oh... I knew that, duh... :oops:

I think you guys are looking at low discharge the wrong way round, I believe low discharge in this instance refers to low voltage not low ampage ("C" rate)
say you've set up a new car and want to know if its going to make the 20minute race time why risk running your expensive race pack right down to the LVC and reducing its lifespan if you can get a dirt cheap pack to test it out and adjust your gearing if necessary before doing 20 mins for real. The same applies to planes even more so, as when flying certain maneuvers if you where to hit LVC it would mean a certain crash most people time their flights so they never hit LVC, but how do you find out what that time is? you turn the LVC off or set it to 1 cell less than you have so it wont kick in then fly agressively till you hear a reduction in RPM or performance and land ASAP then set the timer a couple of minutes short of what you just ran and set the LVC back up, now when you fly you know you will never hit LVC but you have just overdischarged a pack, do you want that pack to be your favorite thunderpower pack or a turnegy pack that has higher than normal self-dishcarge and takes forever to balance but was dirt cheap?


I'm not surprised your battery got hot doing it like that, I am surprised you didn't puff it though, you were lucky not to overdischarge it. I have jumped a neighbor's car with a turnigy 30C 4s 5Ah pack but I had him get in and try to crank it, then applied the bullets to his battery lugs and presto it turned and fired straight away, total connection time less than 3 seconds and no chance of overdischarge. The 8guage wires got warm so I suspect it was pulling 3-400A but as anyone thats ever shorted a LiPo can tell you, LiPos are very good at high current short duration bursts, its heat build up that kills them.

Here's a short video from HK showing how they sort the "B" grade cells from the rest. Wish they would say what kind of tolerances they allow e.g. what is the max internal resistance an "A" cell can have.

<iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/yawevd4bec0" frameborder="0" allowfullscreen></iframe>