Originally Posted by
SushiHunter
True or False: are LiFe batteries more safe or just the same as Lipo's? The guys at my LHS seem to be pushing the idea that LiFe's are much more safe. And is it necessary to use Lipo's over LiFe's or is it just a personal preference type of deal?
LiFE or the genuine A123 batteries are significantly safer and tolerate abuse much more readily than any LiPO. I'm not sure exactly how the prismatic LiFE cells would react to being exposed but I suspect it wouldn't be anything like the LiPO. The A123 batteries are in cylinders and if things go really bad, you get a harmless venting of the cell out of a plugged hole in the top of the case designed expressly for such an event. Remeber that the original A123's were designed for use in DeWalt cordless power tools and those things really take a beating when used commercially.
As to whether it's necessary for one battery or the other, that's kind of a yes/no proposition. The nominal voltage on the LiFE/A123 is 3.3 volts per cell where the LiPO is 3.7 volts. So you have LiFE/A123's coming off the charger at 7.2 volts (two cell pack) and dropping pretty quickly into the 6.6 volt range where a two cell LiPO comes off the charger at 8.4 volts and technically by the time it hit's it's nominal voltage of 7.4, it's actually dead.
So it depends on what you are trying to run whether or not it will work with LiFE/A123's because of the lower voltage output. 2 cells may not be enough and 3 cells too many so you are stuck with a 2 cell LiPO.