Metal-organic framework for stable cyclability of Li-S batteries for space missions

The chemistry and technology of batteries are one of the key factors limiting the performance of satellites, space stations and vehicles in many space missions. Energy storage systems in space applications have to be able to operate in extreme environmental conditions, including pressure, temperature and radiation. In the space industry, it is favourable to take benefit of the latest and best battery technology. Long life cycle performance is necessary to carry out lengthy programmes. Lithium-sulphur batteries are regarded as one of the promising technologies for next-generation batteries due to their high theoretical capacity, energy density, the abundant and low-cost sulphur resources. However, lithium-sulphur batteries have some limitations which have to be solved before commercial application. One of the main shortcomings is the shuttle effect of lithium polysulphides during cycling. Polysulphide shuttle can be suppressed by application of porous matrix in the cathode material. In the proposed approach, the metal-organic framework MOF-76(Gd) was applied as a support for sulphur in lithium-sulphur batteries. MOF-76(Gd) as a porous and conductive part of cathode material shows successful sulphur capture and encapsulation. Sulphur encapsulation was accompanied by stable cycle performance and high efficiency. Consequently, the cathode material displayed a high initial discharge capacity of 687.4 mAh g-1 (3.42 mAh) at 0.5 C, and after 50 cycles, the capacity reached 104 % of the original value.