Fast-charging lithium-ion batteries at low temperatures using a high-capacity phosphorus-based anode

Highly reliable fast-charging at low temperatures is critical for the advancement of lithium-ion batteries. Despite the safe lithiation potential and high theoretical capacity of a phosphorus-based anode, its decreased Li + transfer leads to reduced capacity utilization and structural variations. We report a black phosphorus (BP)-based anode with fast-charging ability at low temperatures. The design involves BP-Mo particles incorporated with Sn 2 P 2 O 7 , an active Li + reservoir, facilitating fast and uniform Li + diffusion and inducing stable Li 3 P-based solid-electrolyte interphase. The high-mass loaded BP-Mo/Sn 2 P 2 O 7 anode delivers a capacity of 5.6 mA h cm −2 and 751 mA h g −1 at −10°C and 4C, and 4.9 mA h cm −2 and 691 mA h g −1 at −30 °C and 2C, with 79 % and 75 % capacity retention after 300 cycles, respectively. At −50°C, the initial capacity of 616 mA h g −1 retains 92 % after 175 cycles. Under these two conditions, the full cells of BP-Mo/Sn 2 P 2 O 7 paired with LiCoO 2 cathode show comparable stable fast-charging ability at low temperatures, and the pouch cell has a capacity retention of 88 % at −10 °C and 2C after 150 cycles.