Been doing some reading on LiFePO4 battery safety & abuse tolerance. All I have to say is this is really incredible technology.
They withstand incredible degrees of overcharge without significant damage (some maufacturers have tested to 10 volts on a single cell without significant damage other than somewhat shorter cycle life).
They can in some cases withstand overdischarge with minimal damage i.e. shorter cycle life.
Withstand short circuits without safety issues
Withstand being punctured without serious safty issues.
Withstand high temperatures up to 300 degrees F without issue
Able to supply very high power without excessive heating. Temperatures remaining at levels that can be touched by human hands without being burned & for the most part remaining comfortable. (110degrees F)
Due to ability to withstand overcharge they are also self balancing so they can be charged in a serial connection without charge imbalance as long as you fully charge the pack.
These batteries are safe for the environment.
Other Than capacity issues which are improving these look to be the battery of the future. Thier safety & abuse profiles appear to exceed that of all other batteries in high abuse situations, even the stallwarts of lead acid (explosion potential during charging due to the generation of hydrogen & oxygen gasses, also environmentally hazardous) nickle metal hydride (excess heating under load may cause leakage & nasty burns when handled after subjection to high loads that significantly exceed max disharge or charge rates) & Nicad (same as Ni-MH but less pronounced but with far greater enviromental hazard)