Grimracer Lipo battery swelling

[jetskier]

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

[siberianhusky]

Two different guys I run with have had 2s 5000mah Grimracers puff in bone stock UL-1s in the last month or so, never run down to LVC, properly charged, one with the stock plastic prop the other with the suggested lifter prop from AQ.
Neither set of batteries had more than a half dozen cycles. Think one set went after 2 runs!

[jetskier]

are you still using them? and what is the warranty regarding these batteries, they cost quite a few $$$. I've also always charge and set my charger @ 1C which is 4.2a and even lower on my charger about 3.9a that's all it can reach charging a 4S. BTW my charger is a Hyperion EOSO606i ac/dc so therefore I really don think I'm doing anything wrong or abusing these batteries.

Two different guys I run with have had 2s 5000mah Grimracers puff in bone stock UL-1s in the last month or so, never run down to LVC, properly charged, one with the stock plastic prop the other with the suggested lifter prop from AQ.
Neither set of batteries had more than a half dozen cycles. Think one set went after 2 runs!

[siberianhusky]

No not being used, they were returned to the local hobby shop, one of the guys who had them puff is an employee, pretty sure they were replaced.
I'm positive that these packs were not abused, neither guy has a charger than can charge at much more than 1C.
Stock Aquacraft boats running the suggested Aquacraft batteries, don't really know what else to say, last year people were raving about them, the first four 2s packs I've seen run puffed almost right away in setups drawing less than 60 amps, Richard was even running his Eagletree Logger so we know what the amp draw was.....
Could have been a bad batch, they were purchased from the same shop within a week or two of each other.

[3b3b]

I too had a 4s 1p Grim puff on me. Ran it in an all stock Revolt. I called AQ, took a picture and sent a copy of purchase, and they sent me back a replacement.

[jetskier]

Thanks, Ill try that.

I too had a 4s 1p Grim puff on me. Ran it in an all stock Revolt. I called AQ, took a picture and sent a copy of purchase, and they sent me back a replacement.

[jetskier]

not good!!! for such an expensive battery, the warranty is only 90 days.

[longballlumber]

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.
We did have a club member have some start to puff slightly, but we came to the conclusion that he had made some calculation errors in his effort to charge multiple packs at one time and was charging above the manufacturer’s recommendation of 1C.
Now, I have ran into a couple of instances where some cells in packs were “soft”, but after a couple of cycles on my Hyperion charger they were fine.

Are you seeing any voltage difference in the cells? In other words, do you have a bad cell? What about charge time, is it taking longer to charge/balance one battery over another?

Later,
Mike

[jetskier]

the battery still runs and charges normal to me, but I'm still fairly new to using lipo. I use about 2500-3500mAh that is what the charger reads when done and the performance to me seems to be the same. My Hyperion can't even reach 1C when charging these 4S batteries so there is no way that I am charging them over the limit. Looking at the pics of the amount that it swelled, would you guys use it if charged outside and/or in a flame proof bag?

[Brushless55]

First off you are not doing anything wrong with these packs..
second I have several packs that have a slight swell to them and never have an issue with them..
if they are not heating up they should be just fine..
I did have a Hayin pack "puff" on me after one of two runs in a PSpec boat under only about a 65amp load and that one I tossed!

[jetskier]

as what you can see from the pics.. does mine fall into the slight swell use at own risk or major swell toss it category. I apologize for dragging out this thread. just hate to toss an expensive battery if it still have some good life for recreational use.

[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

[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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[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.

[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.