2nd generation AirPods are the same design as the first generation but have updated features. [1]https://www.apple.com/newsroom/2019/03/airpods-the-worlds-most-popular-wireless-headphones-are-getting-even-better/ The new AirPods come with either the standard charging case or the new Wireless Charging Case. Each case holds additional charges for more than 24 hours of total listening time.
According to Official Apple Support Center, [2]https://support.apple.com/kb/SP792, just 15 minutes in the case gives you 3 hours of listening time or 2 hours of talk time. 2st gen AirPods deliver up to 5 hours of listening time and up to 3 hours of talking time on one charge which takes about 30 minutes in the case.