Top 10 Top 10 Most Fuel-Efficient Hybrid Cars by Frédéric Mercier May 20, 2019 Photo: Hyundai1. Hyundai IONIQSurprise! The Prius is not the king of hybrids anymore. That title goes to the Hyundai IONIQ, which manages to burn a mere 4.1 L/100 km. By the way, it's also available in plug-in hybrid and electric configurations. « PreviousNext » Share on Facebook Share: