[NSRCA-discussion] charging

[george w. kennie]

This is just an FYI based on my experience.
At the WRAM Show I attended a seminar by the Kokam Battery guys and was advised that it would be completely safe to charge my Lithium Poly batteries at a rate of 3C if one was using one of their Balance Pro Chargers. Well, needless to say, I didn't purchase one of their chargers, however, after hearing about several others who were charging at 3C I decided that I would try the 3C rate and find out what my experience would be like.
I have some small packs for foamies so I decided to try one of them expecting to find some negative result, but the opposite seemed to be the case. 
A couple of weeks ago I attended a contest where I was shooting my mouth off about how I had been charging at 3C and was brought up short by one of those listening and advised that charging at this rate would cause the batteries to overheat, to which I responded rather emphatically that my batteries were remaining cool. This particular gentleman became rather insensed and insistant that he knew for a fact that the heat build-up would be destructive to the health of the batteries. The gentleman walked away with a look of disgust and I felt bad that I had come across so forcefully (happens too often).
Well, the gist of all this is that this A.M. I went to the flying field and informed all in attendance that I was intending to perform and experiment in which I would charge a Lithium Poly pack in 12 minutes at a rate of 5C and we would see what would happen, I being ready to sacrifice the pack if that indeed took place. Well, in 12 minutes exactly, the charger shut down and indicated that charge completion had occurred. I immediately disconnected the pack and ran to the rest of the group in attendance and had everybody feel the temperature of the pack and to everyone's amazement the pack was not even luke warm. I subsequently flew the pack and thought that I got a little longer flight time than I normally do (probably all in my head). Now, these packs have never been balanced, and in fact have no balance plugs. 
So, am I recommending that everyone start charging at 5C? Definitely not !  I'm certainly no battery guru, but I am of the opinion that there may be a lot more for us to learn about the current technology and I'm certain the developments in the near future will surprise many (including me).
Georgie
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