Why is my pack getting so hot?

[Lessen]

I don't get this electric stuff. I put two Venom 4600 packs on my Intellipeak twin charger a while ago. The one pack just finished but othe other is still going. The first one got very hot (max 158*) and the one that is still going is up to 155*. I imagine it'll beep off very shortly. The last time these packs were used was in an EMaxx so I imagine they should have discharged approx. the same right? At any rate, they are 4600 packs being charged at 3.5A. The charger is fixed at that rate so it is what it is. The packs are simply lying flat open on the shelf so it's not like they are not able to dissipate heat because they are mounted in the truck and partially enclosed. I wouldn't think there is any way these should be getting anywhere near this hot as this rate of charge. ????

what the dilly?

 

[alpinehyperlite]

I charge lipo and nimh batteries, and i have never had one over 100 degrees while charging. The nicd 7cell got to 100 before, but thats it.

 

[Lessen]

I just looked at that other pack again and disconnected it.. 170*+

That's freakin' rediculous. they are definitly way too warm but I'm gonna take my temp gun to work and see how accurate it is.. just for the heck of it. I don't get it. I know these Venom packs aren't the highest quality but I got them in a good emaxx package deal and they were not used very much. They were in relativly good condition aside from some broken silicon and I rewired and wrapped them before I used them. From what I gather I imagine they've never seen anymore than a 3.5A charge. :shrug:

 

[robmob]

Cripes.

I would be questioning the peak detection on that charger.

They should not get that hot no matter what the charge rate.

 

[Lessen]

Do you think it could be these Venom packs? I just ran both but not very long. I ran one for 15 minutes before I started to see power loss. The second one I only ran 10 minutes when I saw power loss. I stopped right away and took a look at the pack. I noticed this 'wet' look at the end of the pack coming from underneath the end cover. that particular cell was 170* in only 10 minutes of runtime (mamba max 5700). I think these packs might just be junk.. well they're definitly junk now but I don't think they are very good quality to begin with.

Here you can see the moisture I'm talking about. Sorry for the junk photo, my wife has the good camera.

I think I might very carefully charge my good SMC pack on that charger and see how it does. Of course I'll keep a close eye on the time and temp. I'm hoping it's just crap packs and not the charger. The charger seemed to work fine untill the other day. :shrug:

 

[SMaxxin]

I'm with Rob, look at the charger. The Intellipeak twin charger is not the best, I would ditch it and get something a little better. I made a y harness for my Hyperion and can charge two 6 cell packs with no problem and they never get hot.

 

[abadk9420]

Cripes.

I would be questioning the peak detection on that charger.

They should not get that hot no matter what the charge rate.

+1 on what Rob said, I also think it's time to invest in a good charger...

 

[Lessen]

Well, I'm not gonna blame the charger just yet. I'm going to do some experimenting first.

I have my good Intellect 4200 pack on there now. I have a timer set for 1 hour 12 minutes and I'll be temp checking ofton.

 

[Lessen]

yep, I'll have to agree. It's not peak detecting. That really sux cuz this thing is practically brand new. I got it in an EMaxx package on Ebay. The good thing is that it charges fine, I'll just have to manually pull the pack when it's time.

Intellect 4200
72 minute charge @ 3.5A
T-60 minutes - 92.8*
--47 --------- 98.7*
--33 --------- 100.6*
--20 --------- 104.1*
-- 8 ---------- 105.4*
72 minutes --- 109.4*
+ 3 minutes -- 115.1*

 

[Lessen]

Ok, I'm just continuing the statistics here to showcase some things.

I just charged a pair of Venom 5000 packs on the twin charger. According to the match it should take approx. 1 1/2 hours. Didn't get there. I pulled them off at around an hour because they had gotten too hot. However, the temps weren't even consistant. One cell was 150* while another cell in the same pack was only around 120*. My Intellect pack was nowhere near that inconsistant during the charge and didn't even get that close to 120* after 60 minutes of charge. So no, the charger may not have peaked my good pack but the good pack also charged consistantly cooler than these crap Venom packs. I imagine the cardboard type tubes that they put the cells in has a little to do with the heat retention. but the cells definitly are not as high of quality. I'm just glad I didn't spend retail on them...

I wish I had a voltmeter to see how charged my Intellect pack is. I'm curious if the charger would have peaked if I let it charge for just another minute or so. I was wary to let it go though for the sake of a quality pack.

The thing is.. considering the temp of todays charge of the Venom 5000 after only 60 min. and the temp of the charge of the 4600 after peak sort of indicates that it peaked correctly according to the math. Definitly too hot but the charger doesn't know that unless it utinilizes a probe right?

 

[ohmygahitscoby]

You should get one of those digital peak chargers or anything that is digital like the Duratrax Ice. I have the Piranha Digital Peak and it never false peaked me, and it lets me see how much MaH it has charged the battery pack. The only problem is that it's not a double charging one like the Intellipeak Twin.

 

[Lessen]

Yeah, I should. I would, if I could. However, I don't have the extra couple hundred dollars to spend on new electronics. Actually, I have the Intellipeak Deluxe also and it's never given me any real problems. :shrug:

 

[Lessen]

Well, just to note some of the things I've been looking at. There seems to be nothing wrong with the charger. I charged one of my Venom 5000 packs on it today and it peaked just fine. Now it wasn't completely discharged either cuz it only took 30 minutes to peak. At any rate it definitly wasn't a false peak either because I ran that 5000 and my IB4200 today in my lazer and the runtimes were reflective of their capacities. I also discharged both of the Venom 4500 packs at 10A and they just barely became warm to the touch by the time they were finished. I tried to run one of the 4500 packs yesterday and got very little power out of it. I'm gonna charge up the other 5000 pack tomorrow and run it through my lazer to gauge the runtime and power but I have a feeling it will be ok. The one thing that is consistant through all of these trials is that these Venom packs get a good 20* hotter through both charging and discharging as compared to my IB pack, even the 5000 pack was nearly 180 degree after I ran it today, but my IB pack didn't get past 150.

 

[sweetdiesel]

The problem with chargers that don't have adjustable delta V cutoff is that every battery pack will have a different appropriate value. If the delta V cutoff is fixed, you will always have a mix of some packs that false peak and some that overcharge, even when running packs from the same manufacturer and capacity rating.

Make it easier on yourself.... go lipo.

 

[Lessen]

The problem with chargers that don't have adjustable delta V cutoff is that every battery pack will have a different appropriate value. If the delta V cutoff is fixed, you will always have a mix of some packs that false peak and some that overcharge, even when running packs from the same manufacturer and capacity rating.

Make it easier on yourself.... go lipo.

Yeah, I hear ya. Definitly not in the cards. Not very high on my list either actually.

I just don't want to spend money on things that I realy don't need ya know. I don't want to ditch a halfway decent charger because I got a couple junk packs that may be falsly indicating that it's bad. Out of all my r/c's I run that Lazer the most, and probably not more than 2 hours/month. To me, it's just not worth spending big bucks on a really good charger. I just want to make sure I have something that's relatively dependable and these seem to work ok.

 

[Lessen]

There's nothing wrong with this charger. I just did my other Venom 5000 pack from a complete discharge and it peaked as expected (by approx. time) and only hit 142* max. Those 4500 packs are most likely shot. Not sure what happend to them though... :shrug:

 

[ohmygahitscoby]

This just suddenly happened to me too after discharging my packs. I used my Tamiya discharger. What happened was it didn't notify me that it was done discharging by turning off the LED, so I let it discharge for quite a while. Then this happened. But the battery only hit 140F when I was charging it. This is fine right?

 

[Lessen]

I'm pretty sure 140 is ok, It's when you start approaching the upper 100's that things start going bad I think.

is that strictly a discharger?

my Intellipeak Deluxe charger switches to trickle charge automatically once it senses discharging is complete.

 

[yellowisthefastes]

I just created a post similar to yours. Same charger but I dont think my batteries got as hot. I could hold them in my hand and they were hot but not too hot to hold. I had moisture in on of my packs as well as some melted plastic. These packs were brand new Orions. Would the batteries be bad now. I dont want to hook them back up until I find out what if anything is wrong, as I dont want to mess up my other pack. I am hoping the one pack is not ruined.

 

[ohmygahitscoby]

is that strictly a discharger?

It's a discharger that has an auto-cut off so it doesn't discharge it too much. It did auto-cutoff a few times before, but now it just doesn't want to.