Probably inappropriate for humor here, so I removed my own comment.

Dave called these incidents rare, but if any commercially produced battery had this kind of failure rate it would have been recalled long ago. Even 1 in 100,000 is unacceptable and we seem to be 100X that. Modellers have an inherent expectation of disaster so we just chalk it up to experience and move on, but a major loss seems inevitable.

I also cringe at the thought of damaged batteries being mailed back to the distributor and ending up on a commercial aircraft. They should be sent hazardous ground shipping but since the cost would be excessive, damaged cells should be diposed of safely.

With the high initial cost, short life span, high failure rate and risk of major fires, I think the true cost of LiPo is very high. I am concerned that some try to suggest otherwise.

Rick (who saw his first lithium battery fire 25 years ago)

Rick, for the record, I said relatively rare. I meant that in the context of a product that is known within the industry to be hazardous when used outside of generally accepted parameters. To the best of my knowledge, e-flight is the only area where Li-poly cells are regularly being used beyond the limits for which they were originally designed. These problems should not be unexpected, and many people appear more than willing to put up with the risk and cost in return for outstanding performance.

Especially those who see very little risk when these batteries are treated as they are supposed to be treated. If I have any sort of incident after charging at 1C and discharging to 3.7V per cell I'll be absolutely shocked.

Usually the reward for pushing these cells too much is catastrophic failure.

..just thought I would post a cross reference to another thread which talks about a possible new generation of cells that the mgr suggests will be safer .....

http://www.rcgroups.com/forums/showt...ghlight=Lipoly

Bill

Sorry to hear about the loss. Everytime I read a story like this it sends shivers up my spine.

I have a orbit microlader charger as well. One older version of the software for it would auto detect the number of lipo cells and immediately begin charging. You could manually correct the cell count if required. I have seen this version of the software detect the wrong cell count before on some of my packs. The newer versions of the software do not automatically charge. You need to manually confirm the cell count detected by the charger. Also the newer version of the software detects cell count much better. I haven't had it make a mistake yet.

Take Care,
Brendin

I wonder if a device that monitored the temperature of charging cells and turned the charger off at a certain danger threshold temperature could prevent fires?

Problem with temperature measurement is that with a multicell pack, which cell are you going to monitor? If the problem is one of an unbalanced pack, you'd have to have some luck to pick the right cell, and what if it is the middle cell in a 3 cell pack. The Triton charger as well as some others have a temp probe available. As I recall one incident, the cell ballooned and the Temp sensor fell off.
h

Or the pack hits thermal run-away before the sensor shuts the charger down.....