This morning I accidentally proved why I wanted the safety of li-ion instead of lipos. I was doing a top speed run with my Stampede and had the batteries strapped to the top of the chassis. They were the highest thing on the truck, because the body posts were ripped up from previous crashes. Anyway, as I was slowly getting up to top speed, I nailed the throttle once I thought that the pede was going fast enough to not wheelie. Unfortunately, I underestimated the power of the emolis, and the truck flipped on it's back and skidded about 50 feet on top of one of the battery packs!!! I ran to the truck, and the gps said that it was going 44 mph when it flipped! The truck has enough power to wheelie onto its lid even with a swami bar at 44 mph!!! I managed to scratch up the controller, too. Here's what the battery looks like now.
You can see the deep scratches in the shell of the two top cells. Correct me if I'm wrong, but wouldn't a lipo catch fire if subjected to such abuse?
The batteries weren't hot, so I figured they were still ok. I strapped them under the chassis this time and tried again. I was very careful with the throttle and managed a top speed of 57.7 mph. I was expecting over 60 mph, but I think the drivetrain gears may not be meshing well at such high speeds, because the truck was lurching a little bit.