Blew up an EP4600 cell tonight..
12-28-2007, 02:18 PM
#31
I had issues with some brand new 4200's a while ago and wont ever go back to nimh.
I have been flying electric planes on lipo for some time with no issues, so I got some Trackpower 4900's which have been excellent. I would only ever use HARDCASED lipos. I use them in my planes and for racing, kinda double duty
. I now have 3 packs, and the oldest pack has the same punch as the newest pack.
The rule used to be "if you look after your nimh they should perform well and last a while" . Well this is certainly not the case anymore, with new cells blowing up left, right and center.
On the other hand with Lipo, the rule still applies, as long as you look after them - charge at 1C, with a temp sensor safety cutoff - they should last for ages (several hundred cycles) and most likely be safer than the current generation of nimh.
Pete
I have been flying electric planes on lipo for some time with no issues, so I got some Trackpower 4900's which have been excellent. I would only ever use HARDCASED lipos. I use them in my planes and for racing, kinda double duty
. I now have 3 packs, and the oldest pack has the same punch as the newest pack. The rule used to be "if you look after your nimh they should perform well and last a while" . Well this is certainly not the case anymore, with new cells blowing up left, right and center.
On the other hand with Lipo, the rule still applies, as long as you look after them - charge at 1C, with a temp sensor safety cutoff - they should last for ages (several hundred cycles) and most likely be safer than the current generation of nimh.
Pete
12-28-2007, 02:18 PM
#32
i am not expecting the matcher to answer right away..i e mailed the matcher before i posted this...like i said earlier when i wanted to buy from him he was returning e mails at 9:00 at night....i know full well this is a holiday weekend thats why i am giving it time...
i will wait until after the holiday to call him if i get no response to my e mail...
as far as drama...yeah it is pretty dramatic wondering when the next little time bomb is going to go off...
the cell manufacturers should be held responsible for any damage done...the first thing the shop owner asked me was is there any damage to the carpet....luckily there wasnt but had there been who would have been out $$ for that...
i run high performance boats most of the year and this is my winter hobby...yes we push the envelope with doing things in that as well but any manufacturer that builds a motor or something takes responsibility if there is an issue...
i had no idea that the battery situation was as bad as it is or i would have never gotten back into this....i am hearing horror stories left and right now...
as far as LiPo is concerned...these seem worse to me...see video below....
http://www.commonsenserc.com/LipoSafe_promo.wmv
i will wait until after the holiday to call him if i get no response to my e mail...
as far as drama...yeah it is pretty dramatic wondering when the next little time bomb is going to go off...
the cell manufacturers should be held responsible for any damage done...the first thing the shop owner asked me was is there any damage to the carpet....luckily there wasnt but had there been who would have been out $$ for that...
i run high performance boats most of the year and this is my winter hobby...yes we push the envelope with doing things in that as well but any manufacturer that builds a motor or something takes responsibility if there is an issue...
i had no idea that the battery situation was as bad as it is or i would have never gotten back into this....i am hearing horror stories left and right now...
as far as LiPo is concerned...these seem worse to me...see video below....
http://www.commonsenserc.com/LipoSafe_promo.wmv
Last edited by ghost28; 12-28-2007 at 02:32 PM.
12-28-2007, 03:10 PM
#33
drama, drama
This has all been rehashed many, many times on rctech.
I would like to know which racers asked for ever increasing capacity and voltage? It seems that racers were doing fine with gp3300. Stock and 19t racers had capacity left over as long as they were not completely overgearing the motors. Of course the "pros" were having trouble finishing races with 8t modified motors for 5 minutes. So their answer was ever increasing capacity cells.
Unfortunately, the more capacity you cram into the same size cell (more or less), the less reliable that cell will be. To cram that capacity into that cell, you have to use a denser storage material and/or you have to make room somewhere in the cell, whether it's using thinner walls, thinner barriers, etc.
When you had gp, sanyo, etc making the batteries, the batteries were made for the power tool market, so an extra .05 voltage output was not that important. Capacity was important at the expense of voltage. Once you started getting r/c specific cells, the same thing happened as happens with all things r/c, performance takes precedance over everything else. Voltage and higher capacity were designed into the cell, and the results when that is taken to the extreme are now coming to light.
So before the "expert" racers blame the "amateur" r/c hobbyists for their demands for higher capacity and voltage cells, I want to know who actually demanded what?
I would like to know which racers asked for ever increasing capacity and voltage? It seems that racers were doing fine with gp3300. Stock and 19t racers had capacity left over as long as they were not completely overgearing the motors. Of course the "pros" were having trouble finishing races with 8t modified motors for 5 minutes. So their answer was ever increasing capacity cells.
Unfortunately, the more capacity you cram into the same size cell (more or less), the less reliable that cell will be. To cram that capacity into that cell, you have to use a denser storage material and/or you have to make room somewhere in the cell, whether it's using thinner walls, thinner barriers, etc.
When you had gp, sanyo, etc making the batteries, the batteries were made for the power tool market, so an extra .05 voltage output was not that important. Capacity was important at the expense of voltage. Once you started getting r/c specific cells, the same thing happened as happens with all things r/c, performance takes precedance over everything else. Voltage and higher capacity were designed into the cell, and the results when that is taken to the extreme are now coming to light.
So before the "expert" racers blame the "amateur" r/c hobbyists for their demands for higher capacity and voltage cells, I want to know who actually demanded what?
12-28-2007, 03:40 PM
#34
Tech Regular
I used to beat the tar out of my YR4 back in the day and it seldom broke. That thing would be a pile today compared to the newer, lighter cars.
12-28-2007, 03:53 PM
#35
Tech Regular
Give a stock racer a choice between the 1.18V 30 amp cells that we used to have and the 1.23+V 40 amp cells that we have now and I can guess at what they will choose.
I have my own ideas on why the cells are exploding but that's another story.
12-28-2007, 05:13 PM
#36
Almost all of the stock racers have been asking for more voltage since day 1. That's why we have voltage on the matching labels. Stock class batteries are commonly advertised based on voltage because that's what a lot of the stock racers want.
Give a stock racer a choice between the 1.18V 30 amp cells that we used to have and the 1.23+V 40 amp cells that we have now and I can guess at what they will choose.
I have my own ideas on why the cells are exploding but that's another story.
Give a stock racer a choice between the 1.18V 30 amp cells that we used to have and the 1.23+V 40 amp cells that we have now and I can guess at what they will choose.
I have my own ideas on why the cells are exploding but that's another story.
I'm wondering if its voltage we were wanting rather than the run time.
My nicd's had all the punch you could ask for. I guess once the nicd's were gone the voltage became an issue of need.
Those nicd's sure took some abuse.
12-28-2007, 05:40 PM
#37
That is the first time I've seen the footage of a Lipo being purposely abused. But after seeing that, I'd still take lipo over NiMH anyday, And I do happen still use 4200/4600's in my Emaxx and boat! All this exploding battery crap needs to stop! Flying shrapnel can easily take an eye or worse. If you think that lipo video was bad news check this out http://www.youtube.com/watch?v=Xk00EvS25tQ
12-28-2007, 05:51 PM
#38
....when i started in the hobby at 12 years old i would run a pack...battery got hot......barely waited it for to cool........back on charger........run it.....over and over.......cells NEVER popped..........today they are pushing the envelope with mah capacity in basically the same size can.........is Trinity or the manufacturer going to assume responisbility when when one of these batteries blinds someone??? The mah capacity needs to be backed down so longevity can be had again. This is just one more reason to go nitro..........not to mention the cost.............nitro is cheap compared to electric................
and they wont be responsible for a batt that blows up
nitro is not cheaper than elc
and id like to know how you blow up cells,i cant do it,i tried again today and the thing just dosent blow just vents.
maybe ill do a whole pack and short it out ya YA THAT WILL DO IT.
12-28-2007, 06:07 PM
#39
While reading this thread...this happened...my parents are pissed...I was doing my weekly ritual of charging all my ib practice packs when i hear sssssssss so I jumped under my covers and told my mom to run away and BOOM!!1. The EA pack wasn't the one that exploded it just hapened to be a bystander lol. Unfortunate i guess. It eevn burned up the cute notes my girlfriend drew me haha. Guess s**t happens...
Last edited by Jimmy Morris; 12-28-2007 at 06:20 PM.
12-28-2007, 06:26 PM
#41
Ok jimmy so eveyone now wants to know how you abused these cells since some still do not believe it is happening just because they have not been biten yet. So was it dead shorting with a charge still left? Re-peak at 19 amps? Run 5 cells on a 2 turn motor? JK BTW the notes getting destroyed would make even the toughest man cry!
12-28-2007, 06:30 PM
#42
It was actually never run before. I Bought that pack and another one on september 21st, usps lost them for a month..got them in late october..built them and they wouldn't charge. Sent them back and just got them back a few weeks ago. Company said all was good and he got them to take a charge. So tonight I was putting charge into all my packs just because its a weekly thing i do with these ib cells. and blamooo. Charging at 6 amps.. Never had this issue before and hope to god I don't again. Just a fluke incident i guess.
12-28-2007, 07:07 PM
#43
I had a brand new pack explode on its first charge
12-28-2007, 07:41 PM
#45
trinity dont make cells
and they wont be responsible for a batt that blows up
nitro is not cheaper than elc
and id like to know how you blow up cells,i cant do it,i tried again today and the thing just dosent blow just vents.
maybe ill do a whole pack and short it out ya YA THAT WILL DO IT.
and they wont be responsible for a batt that blows up
nitro is not cheaper than elc
and id like to know how you blow up cells,i cant do it,i tried again today and the thing just dosent blow just vents.
maybe ill do a whole pack and short it out ya YA THAT WILL DO IT.
THEY'VE DEMONSTRATED THAT
YES, IT IS