4 ms·
Formic acid contains 53 g/L of hydrogen[1]. The Mirai has a 500 km range, using 5 kg of hydrogen[2]. So you would need 95 L (116 kg) of formic acid to get the
by p1mrx 9y ago
Formic acid contains 53 g/L of hydrogen[1]. The Mirai has a 500 km range, using 5 kg of hydrogen[2]. So you would need 95 L (116 kg) of formic acid to get the same range. The actual tanks on the Mirai (87.5 kg, 122 L) are physically larger, but weigh less.
[1] http://large.stanford.edu/courses/2013/ph240/yoo1/ http://large.stanford.edu/courses/2013/ph240/yoo1/
[2] https://en.wikipedia.org/wiki/Toyota_Mirai#Fuel_economy_and_range https://en.wikipedia.org/wiki/Toyota_Mirai#Fuel_economy_and_...
- bluejekyll 9y agoSeems like a decent tradeoff. The extra weight would reduce the range, but the gained tank space might make that ok?
- twic 9y agoI imagine the formic acid also has safety advantages: it's stored at room pressure rather than under pressure, so the tank can't explode, and if there's a leak, it won't vapourise. On the other hand, it's reasonably nasty stuff, although far from Things I Won't Work With levels of nasty: https://www.cdc.gov/niosh/ipcsneng/neng0485.html https://www.cdc.gov/niosh/ipcsneng/neng0485.html