no way, their whole army? 
Not the whole army, from 240k I believe 40k fell in the battle, 100k escaped and would join Riboku later on and the rest 100k prisoners got executed.
Historically, Kanki released 20+ youngest Zhao soldiers in order to spread the news to all corners of Zhao and lowered Zhao's morale, but idk whether this will happen in the manga, guess we'll find out in the next chapter or two.