Grimracer Lipo battery swelling

[MarkF]

One of the main causes for a battery to puff prematurly is moisture getting into the packs during assembly. China has a lot of humidity and rain and I know they do there best to keep it out. Problem is sometimes it still gets into some of the packs and they don't really know when this happens. Cells are made to the magnitude of 100,000 to 200,00 peices a day in some factories. They can only test so many cells so bad ones do get through. I know when I get a bad pack they always apologize and replace it for me. It's true some factories change formulas because they find out they didn't charge enough to make a profit and it's to late to raise there price. HobbyKing has bankrupted more companys than you could imagine and there web site is banned throughout the entire country of China. This places company's who screwed up in a bad possition and sometimes forces them to make bad decisions. Another reason why you see good and bad post on the same cells is because the product inside the batteries they use are very unstable. This is the product made in China and is very cheap. The good stuff has to be imported in and that is why you have batteries that cost more and some that cost a lot less. The product inside the battery does vary from factory to factory. This of course implies the end user hasn't done anything wrong himself. I know when I run a pack to dead stick it usually starts to puff 4 or 5 cycles later. It's not something you see as soon as you mess it up. I think this leads people to belive they did nothing wrong because it doesn't happen at the time they hurt the pack.

Mark

[Fluid]

...There may be some truth to what Jay said about a compromised batch, but my 2c is that I watched that man improve his speeds with those batteries. There are records on the books to prove it..

I watched too Wilmer. But if you read my post you will see that initial batches are almost always good to set a good rep for the product (Brian's records are examples) - it isn't until later that they begin to seed in poor items. Heck, even a blind hog can find an acorn in a pile of rocks....



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[madmikepags]

If an entire pack swells then it is "usually" user error, if only 1 cell in a pack swells then it is "usually" a defective cell and "should" be replace by any reputable manufacturer.

[BILL OXIDEAN]

I sat up and Witnessed Brian Buass hit over 110 mph on 4s with those batteries, and he's not "easy" on equipment. I'd have to say they're worthy batteries, but I'm not the wizzard of Oz.
There may be some truth to what Jay said about a compromised batch, but my 2c is that I watched that man improve his speeds with those batteries. There are records on the books to prove it..

[3b3b]

2s packs balanced with no increase of heat. I might take a chance and run them with a cut off at 3.7

One thing I noticed on the puffed packs of the 2s and 4s... The runs seemed faster like it was on 5s. Is that an ok or bad sign?

[3b3b]

That's too bad, I bought a pair and haven't used them yet, my Sky Lipo ( 4s, 5000mah) ran for two seasons w/o any problem, but HobbyPartz is always out of stock. I have since switched to Dinogy and they are holding up well.
I really don't know if I should use them, they will be the most dangerous paper weights, lol...

I'm 3 for 3 going bad with Grims. Not sure if it helps but my 4s was purchased from tower the first of June of last year and replacements prolly in August sent from tower as well. My zippies are holding up but with inconsistent balancing. Happy with my Gforce and Skylipos.

[jetskier]

one battery 4200 30C 4s1p setup. no racing.

[detox]

I'm still fairly new to lipo, just wondering how bad is this. I got 4 Grimracer 4200 4S batteries at the beginning of spring and one of them is swelled up. I don't know how bad is the swelling and if I should use it or not. It's the 2nd one on the right. It's only once or twice been discharged on the Revolt to LVC, besides that its always discharged about 1/2 to 3/4 capacity. Also, the right one is looking a little swell but not as bad as #2
Thanks

Did you use 4s2p or 4s1p setup? My 4200 Grimracer packs are swollen also (six lap heat race LSH class).

A six lap heat race using 4s1p will certainly make one of these 4200 packs swell, heat up and slow down. I wonder if the 5000 versions do any better in a six lap heat race. I know the Hyperion 5000 work verygood. Been wanting to try the Neu 6000 packs.

[jetskier]

Just used mine today. ran good/warm but I cut the my run time shorter the the rest. and charged good and balance, took in about 2300mAh and cool.

I also have a pair of 2s 5000 40C that are puffed. They charge ok and balance but I too am leery of using them. But have been without a problem...knock on wood...just don't run them close to LVC .

[bandanabob]

I also have a pair of 2s 5000 40C that are puffed. They charge ok and balance but I too am leery of using them. But have been without a problem...knock on wood...just don't run them close to LVC .

[tlandauer]

Rats! Just got back from running my Revolt and my 2s 5000mah 40C Grims just puffed. Temps came in at 112. And these were the replacements from AQ. Less than maybe 10 runs and over the warranty period.

That's too bad, I bought a pair and haven't used them yet, my Sky Lipo ( 4s, 5000mah) ran for two seasons w/o any problem, but HobbyPartz is always out of stock. I have since switched to Dinogy and they are holding up well.
I really don't know if I should use them, they will be the most dangerous paper weights, lol...

[3b3b]

Rats! Just got back from running my Revolt and my 2s 5000mah 40C Grims just puffed. Temps came in at 112. And these were the replacements from AQ. Less than maybe 10 runs and over the warranty period.

[Shooter]

Wow, scary stuff! Also throw into the mix that there are always COST SAVES later on in the product life which may attribute to some of the poor quality/variation.

[Fluid]

Wow, I am really surprised to see this thread. My experience with the GrimRacer Batteries have been very positive. I’ve been running them exclusively since they came to the market, and I have yet to “puff” anything. I run mostly P-Limited stuff, but I also have a Q sport hydro also....

How can it be that different users have different experiences with the same item? It should not be puzzling by now with years of experience using Chinese products. It is common for the first lots of product from many Chinese manufacturers to be very good, and it is these early lots which will set the reputation for a specific product - LiPos, BL motors, ESCs, etc. Once the rep is made many makers will begin to slip sub-standard products into shipments, but at a low enough frequency for the distributor not to notice. Heck, a few failures are expected, right? The frequency of sub-standard product will increase as the manufacturer strives to get rid of his substandard inventory. Remember that the Chinese never throw anything away, it gets sold somewhere. This explains how some end users have great experiences with a product while others do not - the quality varies widely.

I'm not saying that all Chinese manufacturers do this, but it is very very common and is a fact of much Asian business. I'm not saying it is wrong, just not what Western buyers are used to. This is one reason that Castle built and runs their own BL motor factory in China - they implemented and maintain Western quality control standards for all products produced. Had they let an established Chinese motor maker produce their motors (which would have been far cheaper for them) quality control and assurance would have not been as good....


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[Brushless55]

without having them in my hand to see up close, I would the pack is fine
just as long as the pack does not heat up during charge and the pack balances out fine