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Old 10-17-2007, 11:28 PM   #46
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it is unlikely but possible depending on what type of connectors you were using that there was a short, a shot in the dark, but could happen. atleast we know know it was a losi from fantastic GRAPHITE on the front arms
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Old 10-18-2007, 02:07 AM   #47
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Well I charged and balanced the battery before I left the house, my son ran it for about 10 or so laps. He caught a pipe and stripped the servo horn so I disconnected the battery from the speed control and put the truck in the bed of my truck. The battery is about a month old and it was not swelled or damaged after his run. So as you put I am a dumbass, please enlighten me with all your infinite R/C wisdom what I possibly could have done to make this battery catch fire.
You should have gotten a good lipo.
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Old 10-18-2007, 02:32 AM   #48
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its most likely user fault. how do you know it wasnt crashed hard? how do you know the pack was properly covered, there coulda been a gash in the case and the graphite shorted on it. it could be a cheap ass crappy lipo, then what do you expect? if u disconnected it how do u know the wire didnt touch the graphite chassis shorting it out?

and you shouldnt of left a lipo like that alone in the car by itself, RULE NUMBER 1!!! if your not using it STORE IT AWAY!!!

curious, what brand was it?
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Old 10-18-2007, 04:35 AM   #49
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I think the key lesson here is to at least unplug any LiPo pack and isolate it from everything else. I don't own a LiPo sack, but will get one for my brushless MBX5R. But even the small LiPo's I have been using in my Tx, Rx packs for my Nitro cars and the one starter box pack I always unplug them, fully charge them up and then stick them in an empty drawer in my work bench. They can't short out in there or drain down.
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Old 10-18-2007, 06:35 AM   #50
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Hey D4,
This is my version on my 501x. I got my friend to cut and bend the aluminium for me.

Didn't wanna extend the battery posts and use longer screws so came up with this solution.
Problem is, the bent part that goes into the battery posts is kinda weak and is breaking. Have to epoxy the damn thing. Also scratched up the battery posts quite abit.

I think i'll prefer to redesign this and use a velcro strap to hold down the aluminium casing instead.
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Old 10-18-2007, 06:48 AM   #51
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its breaking at the join? odd.

mine doesnt have a join which is good as there is no stress on it and still even though its thin its strong as hell

as soon as you put a bend in it you got weakness

see what you come up with
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Old 10-18-2007, 07:05 AM   #52
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I have been running Lipo's for over two years now and have not had any problems. Pictures like the one above really scare me because my batteries are permanently mounted in my car. I never take them out.
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Old 10-18-2007, 08:20 AM   #53
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Quote:
Originally Posted by party_wagon View Post
Do the cases companies like orion put on their lipos actualy keep things like this from happening?
Despite the complaints of Orion/Peak packs being overpriced, the cases really do help. A Lipo battery is soft and has no real shell like a sub-C (necessary because the chemistry of NiMh and NiCd have internal pressure). The lipo stuff still has internal components so if the battery takes a hit it can short internally and make for pictures like the one above. Its less of an issue is 2wd buggies and trucks but in TCs and 4wd cars where the batteries are on the sides and exposed to other cars it can be all the difference. Heck, you could drop your battery on the edge of a table by addicent...
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Old 10-18-2007, 08:30 AM   #54
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Quote:
Originally Posted by Davidka View Post
Despite the complaints of Orion/Peak packs being overpriced, the cases really do help. A Lipo battery is soft and has no real shell like a sub-C (necessary because the chemistry of NiMh and NiCd have internal pressure). The lipo stuff still has internal components so if the battery takes a hit it can short internally and make for pictures like the one above. Its less of an issue is 2wd buggies and trucks but in TCs and 4wd cars where the batteries are on the sides and exposed to other cars it can be all the difference. Heck, you could drop your battery on the edge of a table by addicent...
thanks, that gave me a great idea

will make it shortly
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Old 10-18-2007, 09:02 AM   #55
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So why not just run a 2s2p a123 pack if your using a saddle pack? The cells vent so they don't build up pressure and you can charge them at a 2.5c rate. Not to mention they are hard and very cheap. They have a 30c rating(lower ir then lipos so more punch) You can find the cells for around $8 a piece and then all you need is a hypersonic charger and power suply(under $200 for both) which will leave you with a car that has a 6.6volt 4600 mah pack. The pack will not have the same top end speed as a regular lipo, but you will have much more punch so you will be able to gear it a little steeper if you need that top end speed. The a123 cells will actually charge in under 30 minutes too. The cells are a little too wide for 2wd slots, but they are very easy to fit on a carbon fiber chasis like the sbv2 or bj4. To fit the cells in my 2wd I simply took a saudering iron to one side of the battery slot and melted it off of the car. Then I mount all of my electronics on the same side of the car to counter balance the weight. I use the original xxx chasis which holds up very well after the mod. I am also running a 2s3p pack(6900 mah 6.6 volt) which is perfect for 20 minute run times. I am currently using the mamba max esc, it runs flawlessly with the a123 cells and can be programmed for a lower voltage cut off because these cells can be taken down to 4 volts, however the car gets glitchy below 5 so that i what I take it down to. I'm sure that if I invested into that thing for 4cell pan car taking it down to 4 volts wouldn't be an issue.
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Old 10-18-2007, 09:33 AM   #56
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6.6v? too low i reckon compared to 7.2v standard or 7.4v lipo 2s.

also its SOLDERING! 'soll-duh-ring', not saudering!!!!!!!!

what you mean the cells vent? all cells have pressure and should only vent when there is too much gas build up which usually happens with old packs or packs charged badly all the time. also packs with high IR vent more since they get hotter in a charge. the cells shouldnt keep venting all the time.....
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Old 10-18-2007, 09:43 AM   #57
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Ummmyeah...the "L" is silent.

From Merriam-Webster (M-W.com):

Quote:

Main Entry: 2solder
Function: verb
Inflected Form(s): sol·dered; sol·der·ing Listen to the pronunciation of soldering \-d(ə-)riŋ\
Date: 15th century

transitive verb 1 : to unite or make whole by solder 2 : to bring into or restore to firm union <a friendship soldered by common interests> intransitive verb 1 : to use solder 2 : to become united or repaired by or as if by solder
— sol·der·abil·i·ty Listen to the pronunciation of solderability \ˌsä-də-rə-ˈbi-lə-tē, ˌsȯ-\ noun — sol·der·er Listen to the pronunciation of solderer \ˈsä-dər-ər, ˈsȯ-\ noun

Quote:
Originally Posted by d4_racer View Post
6.6v? too low i reckon compared to 7.2v standard or 7.4v lipo 2s.

also its SOLDERING! 'soll-duh-ring', not saudering!!!!!!!!

what you mean the cells vent? all cells have pressure and should only vent when there is too much gas build up which usually happens with old packs or packs charged badly all the time. also packs with high IR vent more since they get hotter in a charge. the cells shouldnt keep venting all the time.....
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Old 10-18-2007, 09:51 AM   #58
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Quote:
Originally Posted by Turbo Joe View Post
Ummmyeah...the "L" is silent.

From Merriam-Webster (M-W.com):
you americans and your SODDA, lol

keep it real in OZ! come on, the game SOLDAT is sol-dat, not so-dat

either way i'm really good at soldering as long as i got a hot iron.

btw, how does mom in america give a 'uh' sound? in australia its mum, 'm-uh-m'. to us it looks like you have to say 'm-oh-m'.

lol, anyways, back to rc, enough of international language tution and discussion.

CANT WAIT FOR MY LIPO!!! i just drilled a hole in my ammo box large enough for wires to fit thru when charging my lipo. also a hole is good as it would allow the gas and smoke to escape and even the pressure if the lipo explodes. if a lipo exploded in a closed ammo box the pressure inside cant change as its sealed so u turn the thing into a bomb itself
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Old 10-18-2007, 09:59 AM   #59
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Quote:
Originally Posted by d4_racer View Post

btw, how does mom in america give a 'uh' sound? in australia its mum, 'm-uh-m'. to us it looks like you have to say 'm-oh-m'.

lf

Uh, because there's an "o" in it?

I thhing the A123 stuff is very intriguing. 6.6v is plenty as there are motor options that would easily close the power gap to 7.2v stuff. You could just motor down a wind or two. With B/L stuff there is no down side to that. If a chassis could be set up to take advantage of the battery's shape that could be interesting too. How about an in-line saddle type arrangement with two battery sticks running down the center line of the chassis along side the drive train. Things like the steering servo and the motor would need to move around but the possibilities are interesting...
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Old 10-18-2007, 10:00 AM   #60
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Quote:
Originally Posted by party_wagon View Post
So why not just run a 2s2p a123 pack if your using a saddle pack? The cells vent so they don't build up pressure and you can charge them at a 2.5c rate. Not to mention they are hard and very cheap. They have a 30c rating(lower ir then lipos so more punch) You can find the cells for around $8 a piece and then all you need is a hypersonic charger and power suply(under $200 for both) which will leave you with a car that has a 6.6volt 4600 mah pack. The pack will not have the same top end speed as a regular lipo, but you will have much more punch so you will be able to gear it a little steeper if you need that top end speed. The a123 cells will actually charge in under 30 minutes too. The cells are a little too wide for 2wd slots, but they are very easy to fit on a carbon fiber chasis like the sbv2 or bj4. To fit the cells in my 2wd I simply took a saudering iron to one side of the battery slot and melted it off of the car. Then I mount all of my electronics on the same side of the car to counter balance the weight. I use the original xxx chasis which holds up very well after the mod. I am also running a 2s3p pack(6900 mah 6.6 volt) which is perfect for 20 minute run times. I am currently using the mamba max esc, it runs flawlessly with the a123 cells and can be programmed for a lower voltage cut off because these cells can be taken down to 4 volts, however the car gets glitchy below 5 so that i what I take it down to. I'm sure that if I invested into that thing for 4cell pan car taking it down to 4 volts wouldn't be an issue.
Where do you find the cells for 8.00 a piece. Aren't you talking about the A123 2s2p, that pack is 120.00 bucks on A123 website.
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