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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>I had forgotten that I have also had a pack with an intermittent wire on the balance lead of one cell.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>I discovered this by accident because I picked up the battery when it was on charge.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>Slight finger pressure would cause the wire to go intermittent so I retired the pack before something worse happened.<o:p></o:p></span></p><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>David Harmon<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>Sperry, OK<o:p></o:p></span></b></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> NSRCA-discussion [mailto:nsrca-discussion-bounces@lists.nsrca.org] <b>On Behalf Of </b>Anthony Romano via NSRCA-discussion<br><b>Sent:</b> Monday, June 13, 2016 3:38 PM<br><b>To:</b> General pattern discussion <nsrca-discussion@lists.nsrca.org><br><b>Subject:</b> Re: [NSRCA-discussion] Lipo fire<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div id=divtagdefaultwrapper><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>I have re-soldered a number of balance tab leads on older packs. On some the wire is a little too stiff and work hardens over time. I was very fortunate that all it did was prevent it from being charged. Perhaps a good routine inspection of packs and all connections would be useful.<o:p></o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'><o:p> </o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>Anthony<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:12.0pt;background:white'><span style='font-family:"Calibri",sans-serif;color:black'><o:p> </o:p></span></p><div><div class=MsoNormal align=center style='text-align:center;background:white'><span style='font-family:"Calibri",sans-serif;color:black'><hr size=2 width="98%" align=center></span></div><div id=divRplyFwdMsg><p class=MsoNormal style='background:white'><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:black'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:black'> NSRCA-discussion <<a href="mailto:nsrca-discussion-bounces@lists.nsrca.org">nsrca-discussion-bounces@lists.nsrca.org</a>> on behalf of Chris Moon via NSRCA-discussion <<a href="mailto:nsrca-discussion@lists.nsrca.org">nsrca-discussion@lists.nsrca.org</a>><br><b>Sent:</b> Monday, June 13, 2016 3:56 PM<br><b>To:</b> Robert Green; General pattern discussion<br><b>Subject:</b> Re: [NSRCA-discussion] Lipo fire</span><span style='font-family:"Calibri",sans-serif;color:black'> <o:p></o:p></span></p><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'> <o:p></o:p></span></p></div></div><div><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>Glad everyone is ok there Robert.<o:p></o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>I have handled and dissected hundreds of different packs during my time in business, evaluating samples etc and I can say with certainty the weakest link in our batteries are the balance leads and their connections to the individual cells. These are very thin wires that typically are spot soldered to tiny tabs on the cells and crimped into tiny pin connectors. Insulation of the balance wires inside a pack is usually a thin piece of cellophane looking tape.There is little to no strain relief for the wires and we handle and flex them every time they are charged. I have seen many break off and touch others creating sparks and possibly could have lead to fires if they were pressed together long enough. I would bet this is what happened to Robert's pack. The batteries themselves must pass through pretty rigorous testing including being crushed with a metal blade without catching on fire before they will be transported from China. These testing documents accompany every large battery shipment so it is highly unlikely one would spontaneously combust. With an older pack, it most definitely sounds like an internal short of balance leads.<o:p></o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>Chris<o:p></o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'><o:p> </o:p></span></p><p style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'><o:p> </o:p></span></p><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'>On 6/13/2016 11:15 AM, Robert Green via NSRCA-discussion wrote:<o:p></o:p></span></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Hey guys wanted to let you know about an incident I had over the weekend that caused some high concern. I flew four flights yesterday, then returned home. I thought I would go back out later and fly three more, so I charged three more batteries. The three batteries on was planning on using, were flown the previous day, and were not overly discharged. I took my kids to the movies as my wife did not want to go, and that turned out to be the best thing for the family. One of my 2014 packs decided that it no longer wanted to live and decided to catch fire all by itself. I have always thought that the best time for these to catch fire, would be during the charge cycle. This incident happened almost an hour after charging the pack. Keep in mind that after I charged the pack, there were immediately put into my flight box for storage until I got back from the movies. After I took them off the charger, the batteries did not see warm in any way, cool to the touch. I have had these batteries for two and as far as I can remember - they where not damaged in any way. Due to my wifes' heroic action, the house did not catch on fire like my toolbox did. She brought them out to the drive way water on them to kill the flames. I have been pretty cavalier with packs, leaving them out once they are charged and not putting them in something safe for storage....those days are done. If this can happen to a battery sitting with a stored charge, I will not longer leave my house or family unprotected. </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>I bought a safe yesterday, but apparently that may not be the best thing for them either as the battery give off a gas and they need to breathe. In other words if you left them in a safe you may be creating a bomb scenario. What I did was - several years ago, I bought a metal ammo case. I removed 3/4 of the rubber around the case allowing for the exchange of air to occur.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>If any one has any other creative ideas on how they store there lipos, please contribute to this thread as I think it is important as a community that we spread the message that this technology which has been proven to be safe for the most part also can be dangerous.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>thanks,</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'> </span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;background:white'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:navy'>Robert</span><span style='color:black'><o:p></o:p></span></p></div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'><br><br><o:p></o:p></span></p><pre style='background:white'><span style='color:black'>_______________________________________________<o:p></o:p></span></pre><pre style='background:white'><span style='color:black'>NSRCA-discussion mailing list<o:p></o:p></span></pre><pre style='background:white'><span style='color:black'><a href="mailto:NSRCA-discussion@lists.nsrca.org">NSRCA-discussion@lists.nsrca.org</a><o:p></o:p></span></pre><pre style='background:white'><span style='color:black'><a href="http://lists.nsrca.org/mailman/listinfo/nsrca-discussion">http://lists.nsrca.org/mailman/listinfo/nsrca-discussion</a><o:p></o:p></span></pre></blockquote><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif;color:black'><o:p> </o:p></span></p></div></div></div></div></body></html>