Thanks for the information. At my job we deal with these lightweight chemistries in batteries for Unpiloted Aerial Vehicles. You can guess the requirements: provide unlimited Whours/kg, tolerate -40 to +80C temps, exhibit lift, etc.
We have been watching very closely the progress in the Lithium Battery world and I am happy to report progress on this technology is quite fantastic. Safety has received important attention too. So not only has progress occurred in the "laboratory" of the RC World (you know... the, "run them at 30C and see what happens" crowd), but manufacturers are doing a bang up job of extending temperature range, energy density and a bit less tendency to start a good ol' Lithium fire. We have never had one catch fire yet, but then again we don't run our batteries at extreme currents. We often have some of the Lithium Ion Polymer packs suddenly decide to expand their casing like a balloon. We have never seen the package burst though. My technician did a little research and found that slowly, very slowly, recharging the pack tends to shrink them back down back to normal. We don't fly these packs again of course, but so far they seem to act normal. We finally got tired waiting for one of these things to self ignite so we took one we pulled from service, but a charge on it and then tapped a nail through it. We witnessed some small jet like flames, but nothing like the way cool over charge tests the RC folks have done with inferno results. Being light in weight makes them attractive options for the backpacker crowd. I am almost ready to consider carrying these things on my body, but not quite yet. I want a little more safety first. Is there a ham web site somewhere that is collecting information on these latest batteries for use in the ham "way?" If not, perhaps I will add that thread to mine. John Kevin Rock wrote: > Better link to Spectrum article on A123: > > http://www.spectrum.ieee.org/sep07/5490 > > Kevin. KD5ONS > > > > On Mon, 03 Sep 2007 15:05:32 -0700, Jim Miller <[EMAIL PROTECTED]> wrote: > >> I've likewise chosen external power for my K2. The ongoing tests by >> the RC >> airplane folks of the Dewalt Lithium Iron Phosphate batteries may >> finally >> cause me to put some batteries in my K2. >> >> Google "A123" for more info. >> >> 73 >> >> jim ab3cv >> > > > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
