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Hi Dave, (slightly off topic) I was reading in todays morning newspaper about the NASA Report on the space shuttle tragedy. Reading about the institutional bias and failures to recognise an unsafe flight condition, made me think about the known problems with LiPo's.
Are we also (the electric RC flight community), so much in love with the light weight and long flight times of LiPo that we too easily dismiss/ignore/minimise the problems? I sure hope not. While we have sometimes had our "issues", I truly feel that our concerns need to be adressed if we are to enjoy the promise of safe electric modeling. Brad |
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I still hink that its all down to sensible precautions.
You can cut your finger on a modelling knife You can glue your jeans to your leg with CA You can rip your fingers on a prop. You can kill someone by flying into them. You can set yourself alight with glo fuel You can fall into a ditch watching your model, not the ground. You can set your car alight with a bust battery. BUT you won't contract AIDS, get a fishing hook in yor eye, get knocked down by a golf ball, get your rib cage or skull smashed in by a horse, fall from 10,000 feet without a parachute, or any number of other things you might get from other leisure activities. We all now know the risks., Its up to taking sensible precautions, or going back to watch 'south park' and the beer..... And that will kill you eventually from heart disease anyway. Waddya want? Immortality? |
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You bring up some good points, Brad. Along the lines of what Vintage1 said, I believe that life is all about balancing rewards against risks and making informed decisions that you're willing to trade off a certain level of risk for a certain level of reward. Needless to say, different people will reach different conclusions on what trade-offs are acceptable to them.
I think the real key is in understanding as best we can the level of risk. The rewards are usually fairly obvious, but risks can be hidden. When looking at risks, it's possible to downplay them if we're focused on the rewards. On the other hand, if we get so concerned with risks that we become paranoid and don't want to take any, then we'll go through life without reaping many rewards. I think these LiPo safety discussions have developed into a healthy discourse with everyone contributing good ideas. I don't worry too much about those of us who read every message in these threads and understand the risks fairly well. I do worry about the casual hobbyists who only read the positive LiPo threads and want to leap in and reap the rewards without fully comprehending the risks. So I think it's good that we continue these discussions and share this information with as many people as possible. |
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vintage1 and Dave, I fully agree with your comments on how to balance risk reward as an individual. We are informed users, and can intelligently make that balance
But what about those "casual hobbiests" and "newbies"? Consider the proud papa who buys his 12 year old son a nice Firebird XL plane and LiPo batteries from TOWER Hobbies this Christmas. Yes, TOWER now sells LiPo's. Will it come with detailed saftey instructions on the dangers, care and feeding of LiPo's ???? The kid then goes out and flys the plane into the side of the neighbors house, calls it quits, and throws it with a damaged battery into the closet on top of his pile of dirty clothes. DATELINE NBC! (substitute BBC for the UK) SHOCK, HORROR, CHILDS TOY CAN EXPLODE! EVIL MANUFACTURES ARE PUTTING TOYS WITH DYNAMITE BATTERIES INTO OUR DEAR CHILDRENS HANDS!! OK, OK, perhaps not this hopefully, but if LiPo's come into widespread use (that's what the manufactures want) does anybody actually believe that EVERY USER WILL KNOW AS MUCH ABOUT LIPO SAFTEY AS WE EZONERS DO? People do not always read the instructions, and do DUMB STUPID THINGS, hey, they sometimes read the instructions and still do DUMB, STUPID THINGS. With the current issues that allow LiPo batteries to catch fire by overcharging, overdischarging, and cell damage, will we the experienced knowledgeable user suffer the consequences of misuse and marketing of a product to an inappropriate market? So what is the answer? I don't know. But that doesn't mean that there is not a problem. Perhaps the answer is to stock up on LiPo's while you can. I'll get off my soapbox now, as we Ezone members are I think, part of the solution, and not part of the problem. Brad |
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Last edited by bradpaul; Aug 27, 2003 at 03:22 PM.
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Brad, as I said in my previous message, I agree with your concern about the casual users and newbies. I think our discussions here have helped raise the level of awareness on this, which is why I think it's important to continue discussing. I'm confident that LiPo cell manufacturers, distributors and retailers are all working on this right now. Like you, I don't know what the ultimate solution will be, but I do feel confident that there will be one. Who knows, out of one of our discussions someone might mention something that will lead to the implimentation of a fix.
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"will we the experienced knowledgeable user suffer the consequences of misuse and marketing of a product to an inappropriate market?"
You can just about bet that will happen if we continue to hear of more fires. If there was a line of toasters on the market under various labels that continually shorted out and caused a fire, they would all quickly be yanked off the shelves by one of the agencies. Sometime do a Google search on "recalls". You will be amazed. We are using these cells in ways that they were never intended to be used and by people who should not be using them. We are using lithium cells without the layers of protection that was provided for them in other consumer devices. In the case of the cell phone, accidents can happen even with the protection, but a lot less frequently than we are seeing in model use. If you missed it, here is another report of a lipo incident. http://www.rcuniverse.com/showthread...75#post1308375 And if you read this post, you will cringe. I wonder where the next fire will occur. https://www.rcgroups.com/forums/show...05#post1228905 |
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You mean the part about trickle charging Li-ion cells for two days, and then getting "brave" and peak charging them?
Ouch! |
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Is anyone keeping track of exploding lithium battery reports? I think it would be good to have a list of links to all of these threads.
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I started a list back in Sep. 2002 when I read the very first post about a member venting a lipo. Oddly enough it was from a member who said that these were very safe cells. I continued it in a text file with just the member's name and few details, but not the links. I had the first 7 ventings listed, but stopped keeping track of them. The number of ventings or fires is well into the 20's now and that doesn't include the dozens and dozens of posts of swelled and puffed lipos.
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To the best of my recollection, the first LiPo "incident" was reported by asperkins a little less than a year ago -- Aug. 31, 2002. He was one of the first (Ralph Weaver may have been the first) to report here on using LiPo cells (Ultralife 700mAh LiPos) from a surplus cell phone pack, and somehow got a short that turned his Ultralife pack into a "smoke bomb."
The thread linked to below makes interesting reading in its entirety because it represents the best thinking on this forum at the time about LiPo safety. No one really knew much about LiPos, and the input we received in that thread from some pretty knowledgeable people in the lithium cell business seemed to suggest that LiPos were safer than Li-ions. Of course, LiPos had not been used prior to that time for such stressful activities as flying electric aircraft. In fact, I don't recall any hints at the time that LiPos had the potential to "explode" in a "shower of sparks" that could result in houses and cars catching on fire. If anyone had any suspicions at the time of what was to come, I don't recall them being shared with the rest of us in advance of the more recently reported events. https://www.rcgroups.com/forums/show...threadid=59306 |
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Last edited by Dave Hederich; Aug 27, 2003 at 09:43 PM.
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I'm surprised that this thread has gone silent. I thought the link I posted in my previous message to the first recorded LiPo incident would generate some discussion. Does anyone who went back and read that thread have any thoughts about it? Did reading that thread have any influence on your current perspective? Just curious.
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