It has been a long time but... I had a battery in my pocket (not sure any more but probably a 9v), no change in the pocket and do not remember what it was that caused the problem (probably my knife) but something apparently shorted the terminals and I felt uncomfortable, jostled my pocket, then warm, then hot and HAD to get whatever it was out. I burned my hand. The battery got MUCH hotter even after it was out. It would have caused a serious burn to my leg had I not removed it. I could only describe the situation as an avalanche failure inside the battery.
I will not forget that experience and never put batteries in my pocket of where they can short any longer. 73, Jim KG0KP -----Original Message----- From: Elecraft [mailto:[email protected]] On Behalf Of Don Wilhelm Sent: Saturday, February 18, 2017 6:01 PM To: [email protected] Subject: Re: [Elecraft] ECOM scare -- FW: Soldering lesson I was involved in product testing in my former career. One large computing machine which I worked on had a backup battery consisting of 4 AA cells, which no-one thought would be a problem, but during environmental testing at shipping extremes, condensation formed and created leakage paths. It was a hard sell to convince management and many engineers that AA cells could cause a problem. The following action was to do extensive testing in the power systems lab in which several destructive tests were performed, which included shorting the battery pack terminals. It is amazing how much current those "lowly" AA cells can produce in a shorted situation. Under short conditions, they are just as powerful as any other battery, but the duration of the huge current discharge is shorter than for larger batteries. Lesson I learned is to be careful with any battery. High density battery chemistries make the short circuit discharge duration longer and can cause more damage. 73, Don W3FPR On 2/18/2017 6:25 PM, Rick WA6NHC wrote: > Don't forget that some of the battery packs we commonly use now > (LiFePo4 is my example) are capable of tremendous current (mine are > 'fused' by a BMS at 100 amps). ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
