Ultralow-Concentration Electrolyte for Na-Ion Batteries

Owing to the smaller Stokes radius and desolvation energy of Na⁺ compared to those of Li⁺, an unusual ultralow-concentration electrolyte is proposed for Na-ion batteries to further reduce the cost and expand the working temperature range, benefiting from the low viscosity of a dilute electrolyte and the formed organic-dominated solid electrolyte interphase. The novel dilute electrolyte chemistry provides new solutions for the operation of rechargeable batteries under extreme conditions, which can accelerate the exploitation of low-cost and durable energy storage systems.