Good info here:
http://www.rcgroups.com/forums/showthread.php?t=209187
Also within this forum.
Goto my site (see sig) goto links. TOP are battery links. Read them.
Educate yourself before you buy them and understand that not all manufacturers use the same quality. I use one that has been in a crash, it's deformed a bit, but it's ok cause I know what the battery will do or not do if it was damaged. I also charge my batteries outside or within a concrete block box that I made (hardscape pavers). Just in case. I've never had a problem. But I also do the best I can to follow the safety guildlines with ALL my batteries. They all have thier dangers. Get to know them and keep you and your family safe.