Large scale applications of metal-iodine batteries working at sub-zero degree have been challenged by the limited capacity and performance degradation. Herein, we firstly propose a Zn-I2 battery working at low temperature with a carbon composite material/iodine (CCM-I2) cathode, a Zn anode and an environmentally tolerable Zn(ClO4)2-ACN electrolyte. The CCM framework with hierarchical porous structure endows a powerful iodine-anchoring to overcome undesirable dissolution of iodine in organic electrolyte, and the Zn(ClO4)2-ACN electrolyte with low freezing point and high ionic conductivity enhances the low temperature performance. The synergies enable an efficiently reversible conversion of Zn-I2 battery even at −40 °C. Therefore, the resultant Zn-I2 battery delivers a high specific capacity of 200 mAh·g−1, which is fairly approximate to the theoretical capacity of l2 (211 mAh·g−1) and a superior cycling stability with minimal capacity fading of 0.00043% per cycle over 7,000 times under 2C at −20 °C. Furthermore, even at −40 °C, this Zn-I2 battery still exhibits a good capacity retention of 68.7% compared to the capacity at 25 °C and a rapid capacity-recover ability with elevating temperature change. Our results distinctly indicate this Zn-I2 battery can be competent for the practical application under low temperature operation.

Fabrication alloy-type anode into nanoporous structure demonstrate great potentials to solve the problems of their volume expansion and electrode pulverization upon cycling. However, the fine regulation of porous structure and quickly achieving a stable interface remains challenge for the alloy anode. Herein, we design and prepare a three-dimensional (3D) nanoporous CuGeAlNi alloy by chemical dealloying method. The corrosion resistance capability of Ni could regulate the dealloying process and thus morphology and porosity of the pre-fabricated CuGe alloy can be effectively tuned. A hierarchical porous structure with 10–80 nm large pores and 2–10 nm small pores on the ligament were obtained. The optimized nanoporous Ge-based anodes delivered a superior electrochemical performance, which presents a high reversible capacity of 540.9 mAh g⁻¹ after 200 cycles at a current density of 500 mA g⁻¹ and outstanding rate performance, which thus endowing a stable cycle performance. These results prove that the Ni-doping approach may offer a facile but effective way for boosting the performance of alloy-type anode for lithium-ion batteries (LIBs).