A High-Energy Aluminum-Fluorinated Carbon Battery Enabled by Chemical Bond Activation in Molten Salt Electrolytes

Aluminum-fluorinated carbon (Al─CF_x) primary batteries show potential in aerospace, military, and related fields, due to the inherent safety and abundance of aluminum, long-term reliability, and high theoretical energy density. However, the practical performance of these batteries is impeded by high energy barriers for Al³⁺ desolvation and C─F bond cleavage, which leads to slow kinetics and thereby restricts the achievable energy density. Here, we report a high-energy Al─CF_x primary battery via a chemical bond activation strategy in molten salt electrolytes. The designed quaternary molten salt contains electrochemically active high-order Al─Cl clusters to accelerate Al³⁺ desolvation; crucially, abundant alkali metal ions activate CF_x's C─F bonds via strong electrostatic attraction, promoting stable AlF₃ formation. Operated at 85°C and 10 mA g^-1, this battery achieves a discharge plateau of 1.75 V and a specific capacity of 897.7 mAh g^-1, outperforming the ionic liquid system (0.21 V, 464.4 mAh g^-1). A high-rate Al─MnO₂@CF_x battery is developed via engineering a MnO₂─CF_x heterointerface, offering a low-cost route for high-energy-density energy storage.