Do power tools really use LiFePO? Based on everything I have seen they all use the common Li-ion chemistry cells. For example a common cell in power tools is the Samsung INR18650 25R, which is not LiFePO I think.
LiFePO has the nice "doesn't blow up and catch fire" feature. Boosted Skateboards first generation used LiFePO, and worked great, but was expensive. So they switched to generic lithium-ion for the second generation. Their battery recall followed shortly thereafter.[1]
[1] https://www.cpsc.gov/Recalls/2017/boosted-recalls-electric-s...