Do I have bad luck with lipos or am I doing something wrong?

[-Dusty-]

So I have had problems before with 3s lipos where they were too heavy and one crushed the other.

So I decided to use 4s just to tide me over til I decided whether to run 2x3s or run a single 6s.

Now the problem I might have now is that both 4s batteries I got seem like there might be some slight puffing on the bottom of the hardcase. Now I haven't even used them much and only hit lv cutoff once. Its been raining here a lot so I have had them in storage at 3.85 for almost 2 weeks. So I don't think its over/under charging or anything like that.

Not sure if Im being too cautious or whatever. For reference I do have a couple 6s now and they sit nice and flush on the table. The 4s don't. Could I have damaged the cells or something?

The one thing I can think of is that they run quite warm. A lot warmer than my old 3s packs. Could this be an issue?

 

[-Dusty-]

Also was wondering what the best way to place the batteries in the car. Should the seam of the hardcase be horizontal or vertical, with my 2x3s setup I think having them horizontal was not a good idea since thats where it caved in at the seam

 

[bicketybam]

If you think that is bad you should see my batteries!

 

[-Dusty-]

If you think that is bad you should see my batteries!

I could just be over cautious. I will keep an eye on them.

 

[Paultro84]

Also was wondering what the best way to place the batteries in the car. Should the seam of the hardcase be horizontal or vertical, with my 2x3s setup I think having them horizontal was not a good idea since thats where it caved in at the seam

Doesn't sound like you're doing anything wrong. I always run my batteries till they hit LVC. I let them cool before storage charging them. Mine are usually around 100-115F after a run. I always check temps on everything right after LVC kicks in. Do you know how hot yours are getting? You can get a temp gun for like $10 if you don't have one.

 

[Paultro84]

My Onyx soft case batteries are a little puffy but they still hold a charge fine and perform just fine.

 

[bicketybam]

I could just be over cautious. I will keep an eye on them.

I’m the opposite. I don’t leave them charged or uncharged. I always do the storage charge. But a few of mine are pretty beat up. When you send it, batteries are bound to take a beating.

 

[-Dusty-]

Doesn't sound like you're doing anything wrong. I always run my batteries till they hit LVC. I let them cool before storage charging them. Mine are usually around 100-115F after a run. I always check temps on everything right after LVC kicks in. Do you know how hot yours are getting? You can get a temp gun for like $10 if you don't have one.

I ran one pack today, didnt even get that warm but I wasn't going hard. Last time I ran these were almost two weeks ago and I did check the temps but I honestly don't remember what they were at. If it was anything past 110 Im sure I would have remembered.

 

[slick2500]

Could also be that the case isn't square.

 

[Paultro84]

I ran one pack today, didnt even get that warm but I wasn't going hard. Last time I ran these were almost two weeks ago and I did check the temps but I honestly don't remember what they were at. If it was anything past 110 Im sure I would have remembered.

I'm not sure what temp is too much for lipo's. Slick2500 might be right. I've only had one hard case battery and it didn't last long. It was a valant or something like that. Cells wouldn't balance right and it took forever to charge. It was a 5200mah and it only gave me 15 minutes of run time. I finally just junked it. Haha

 

[olds97_lss]

Mine have come out of the truck at 124F running SMC 7400mah 2x2S packs stacked up. That's with ambient being 85F. I was also having my esc overheat on me on a relatively frequent basis as I figured out gearing that would work. I ended up dropping down to 14T gearing, but it still overheated on me in the grass, so I replaced my 3.8" trenchers with emaxx tires/wheels that were smaller in diameter and 2oz lighter per wheel. I ran it hard last weekend at 85F outside for 1 set of packs with 14/50, then increased to 15/50 and ran two more sets of packs hard. About 22-24 minutes per set. Nothing overheated/stopped like before, but the packs came off the truck at 122F.

Not sure if I'll try upping the pinion to 16T or not. I'd like a bit more wheel speed... but short of running lower gearing with 6S, I'm not sure I can get away with it.

 

[Crash]

So I have had problems before with 3s lipos where they were too heavy and one crushed the other.

So I decided to use 4s just to tide me over til I decided whether to run 2x3s or run a single 6s.

Now the problem I might have now is that both 4s batteries I got seem like there might be some slight puffing on the bottom of the hardcase. Now I haven't even used them much and only hit lv cutoff once. Its been raining here a lot so I have had them in storage at 3.85 for almost 2 weeks. So I don't think its over/under charging or anything like that.

View attachment 21737

Not sure if Im being too cautious or whatever. For reference I do have a couple 6s now and they sit nice and flush on the table. The 4s don't. Could I have damaged the cells or something?

The one thing I can think of is that they run quite warm. A lot warmer than my old 3s packs. Could this be an issue?

Do you line your battery tray?

 

[-Dusty-]

Do you line your battery tray?

I did put a light foam under but I don't think it would help with hard landings. I fabbed up a little something today with some layered foam and cardboard. Actually seems like it will help with impacts

The thing is, I don't really bash too hard and I mostly use the kraton in my front yard. Soft ground with grass.

 

[Crash]

Thick rubber seems to work pretty well if what you're doing ends up not working. It won't slide or damage a 6S battery

 

[olds97_lss]

Thick rubber seems to work pretty well if what you're doing ends up not working. It won't slide or damage a 6S battery

What is that? Rubber gasket material?

 

[Crash]

What is that? Rubber gasket material?

I got it from the hardware store. Not sure what its called but it the same material used on the base of a wall. Its a hard rubber that works real well with hardcase lipos. I did it about 9 months ago and don't have the original packaging. It came in squares so I cut rectangular pieces and glue them together for the front and back side of the battery tray and then I cut 1 long solid piece to lay on the bottom of the tray. When I put the battery in it it's very snug and fits perfectly.

 

[DaleP]

Dusty,

I read through both of your posts with your batteries. Its your SMC's. I've had the same issues with my SMC's and have 4 packs that are either crushed like yours and or have a bad cell. I have contacted them in the past and they will take care of you, but I have since changed to venom packs that are holding up much, much better for me.

Don't despair man, its just those packs.

Dale

 

[-Dusty-]

Hmm, with all the hype around SMC I thought it would be a safe buy. I got mine from a Canadian SMC dealer, I contacted them before about the 3s and they just told me to salt water the battery. I will see how the 2 4s 7400 mah batteries handle but not really satisfied with them so far. The run times are a lot less then what I had on the 2x3s 5400

I also got 2 6s 4500mah in the mail last week. haven't tested them yet since its been raining forever. Will see how they run.

 

[DaleP]

Yeah, I bought into the hype as well. After getting my replacement batteries from SMC, two 6s packs, They literally went bad after about 5 runs. And that's doing easy laps around the track as I drive with my six year old son and his 2 s truck. And keeping a careful eye on the packs with a venom battery monitor set to go off at 3.6 volts. Sorry guys, and Ill get flamed for this, but my experience with SMC batteries have been sh*t.

Drop the dough on a better battery.

 

[TooTall]

I have a couple SMC 3s packs that were raved about on forums as great lipo's. I think they are 5400 90c or something like that, they suck @$$ so bad, I literally only use them if all my other packs are not available, from the time I pull the trigger on them, they seem like 2s rather than 3s.

SMC may have been the schiznit at one point, but I think they are cutting corners for profit at this point. I have several PowerHobby and RCJuice packs that I would recommend without hesitation. I have a couple 3s PH packs for my Nero that have gone thru hell and back multiple times, and they still run strong every time, they are puffed a little and I will be sad to see them go when I retire them.

TT