A “Lithium-Aluminum” soft pack battery based on aluminum for open-system operation

Because of the high capacity, natural abundance, and safety of aluminum (Al), the Al–Li alloy formed by combining it with lithium (Li) is an attractive anode material. In this paper, we propose a new type of lithium battery that works in an open system and does not require sealing, the “Lithium-Aluminum” soft pack battery (LAB). Al foil is applied to the anode of the LAB, LiCl is used for the electrolyte, and LiFePO 4 is used as the cathode. LAB incorporated Al–Li alloy into lithium batteries in a new way. During charging, lithium deposits in the anode undergo an electrochemical synthesis reaction with Al to produce Al–Li alloys, which decompose during discharge. The LAB has a discharge voltage plateau of about 2.8 V and a discharge capacity of 0.48 mAh/cm 2 (145.5 mAh/g), with the Coulombic efficiency remaining above 90 %. The capacity retention rate is 95.9 % after 600 cycles and still reaches 65.2 % after 800 cycles. Notably, the battery remains functional when bent at will and in a broken or punctured state. Compared to traditional lithium metal batteries (LMBs), our work demonstrates superior cycle stability, a safer operational environment, increased versatility in application scenarios, and reduced costs.