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Old Sep 01, 2011, 09:26 AM
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For storage periods of more than a day, I'd recommend getting below 3.9V and above 3.75V. I've had packs puff a bit after sitting fully charged in the 90F weather here.
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Old Sep 01, 2011, 06:45 PM
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Ah. The storage conditions are usually indoors, around 65-80 depending on the season etc., avg 70-75, and similar to the temp they were charged at. If possible I charge outside in a warmer temp either at the car or field. I figure the temp drop inside should help some.
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Old Sep 01, 2011, 08:04 PM
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I should add the puffing took place in under 1 week.
Keep them under 4V/cell at all times is the best advice.
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Old Sep 19, 2011, 10:15 PM
Leventx
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Hi Guys,, i almost checked all reports about li-po problems,,seems %80-90 of them from 2004 or from early days ... so maybe can we say that now a days battery and charger quality get better ? so not much li-po fire happens anymore ... as i m a person with having more than 30 li-po s on my home , i m trying to be optimistic ,,but sure i ll be more careful i think i ll charge them inside a strong metal box with putting 2 fire distinguisher very close :
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Old Sep 19, 2011, 10:34 PM
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About 10 were reported in the last year and about 54 in the last 4 years. As the use probably has grown tremendously in the last 5 years, one can assume that the better balancing chargers and the emphasis on safety have contributed to the % of fires going down. However, they still are being reported so following the manufacturers safety recommendations is strongly advised.
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Old Oct 14, 2011, 02:49 AM View Post
lxtbattery
A moderator felt this post violated the following rule: Cross-posting. Show it to me anyway.
Old Oct 29, 2011, 01:43 AM
mdv
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My neighbor recently torched his truck while charging. He blamed the batteries but I'm not so sure it wasn't user error. Truck was a total loss.

Quote:
Originally Posted by paratechx View Post
Hi Guys,, i almost checked all reports about li-po problems,,seems %80-90 of them from 2004 or from early days ... so maybe can we say that now a days battery and charger quality get better ? so not much li-po fire happens anymore ... as i m a person with having more than 30 li-po s on my home , i m trying to be optimistic ,,but sure i ll be more careful i think i ll charge them inside a strong metal box with putting 2 fire distinguisher very close :
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Old Oct 29, 2011, 09:25 AM
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My data of over 200 fire reports show that 50% of them are from 2005-2011 time frame. That is in complete disagreement with the conclusion that paratechx has come to.
Lio Fires are still occurring regularly.
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Old Oct 29, 2011, 09:29 AM
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Quote:
Originally Posted by mdv View Post
My neighbor recently torched his truck while charging. He blamed the batteries but I'm not so sure it wasn't user error. Truck was a total loss.
User error? charger failure? Battery failure?
Doesn't make any difference in the end. It happened.
Be careful!
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Old Jan 09, 2012, 03:03 PM
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I almost had a fire last weekend http://www.rcgroups.com/forums/showp...postcount=9903

In this case it was loose wires in the connecter falling out and shorting on a freshly charged pack.

Right now the battery is in a metal thermos, it's not swollen, but I don't feel comfortable trying to hook anything up to discharge it with the condition the wires are in. How should I dispose of it? Would a place like radio shack take it in the state it's in?
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Old Jan 09, 2012, 07:51 PM
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Accidents happen to the most careful users, luckily it didn't ignite.
Were these the main power wires or the balance connector wires?

Can you post a picture?

If the main leads are available, if it were mine I would simply use alligator clips to connect it to a 12V lightbulb (If it's a 3s) (outside in a firesafe location) and let it run down. Remember to snip one lead at a time.
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Old Jan 09, 2012, 10:32 PM
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First time LiPo user..scared stiff!


Not sure if this is correct forum but hopefully moderator will redirect if so.
I am a complete novice wrst Lipols and I am aware that handling correctly is required.
I have just received TWO Turnigy 20-30C 5000mAh (4 cell 14.8 volt.) packs for my scale fast launch. Only one battery to be used at a time.
I have no idea if it needs to be charged first or what.
I have a new IMAX B6AC charger ready to go whenever.
I need someone to walk me through the steps. I have the manual but she all looks a bit daunting and I am reluctant to do anything on my own this first time.
I believe I need to get a low voltage cut out for the boat.
I think the charger handles the cell balancing when charging? Is that correct.
Any help appreciated
thanks
Raynor J
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Old Jan 09, 2012, 10:53 PM
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http://sites.google.com/site/tjinguy...arging-how-tos

Start by reading that article.

Lipo packs come 1/2 charged so it will need to be charged.

A LVC will be needed to protect the lipo.

Lipos can ignite if abused. Follow the rules!

I suggest asking specific questions in a new thread.

Good luck.

Yes, the charger when used in the balance mode with both the main power leads and balance connector hooked up will balance the pack.
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Old Jan 10, 2012, 11:19 AM
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Quote:
Originally Posted by hoppy View Post
Accidents happen to the most careful users, luckily it didn't ignite.
Were these the main power wires or the balance connector wires?

Can you post a picture?

If the main leads are available, if it were mine I would simply use alligator clips to connect it to a 12V lightbulb (If it's a 3s) (outside in a firesafe location) and let it run down. Remember to snip one lead at a time.
It's a 1 cell 3.7v, there are only +/- leads coming off and those are what touched. I'm amazed it didn't blow, I was watching youtube vids of packs bursting earlier that day and got that big plume of white smoke they make seconds before flaming up. The problem is there really isn't much wire left exposed to connect anything to.
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Old Jan 10, 2012, 12:41 PM
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This is a case where I would recommend dunking in salt water. Mix 4 tablespoons of salt in enough water to cover the pack and let it stand for a week outside, than toss it.

The best discharge method is to use a resistance as the salt water method is not a sure fire discharge method, sometimes the internal tabs corrode off leaving a pack that reads 0V but is still charged to some degree.
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