Lithium (Li) batteries are major players in the power source market of electric vehicles and portable electronic devices. Electrolytes are critical to determining the performance of Li batteries. Conventional electrolytes fall behind the ever-growing demands for fast-charging, wide-temperature operation, and safety properties of Li batteries. Despite the great success of (localized) high-concentration electrolytes, they still suffer from disadvantages, such as low ionic conductivity and high cost. Weakly solvating electrolytes (WSEs), also known as low-solvating electrolytes, offer another solution to these challenges, and they have attracted intensive research interests in recent years. This contribution reviews the working mechanisms, design principles, and recent advances in the development of WSEs. A summary and perspective regarding future research directions in this field is also provided. The insights will benefit academic and industrial communities in the design of safe and high-performance next-generation Li batteries.