A group led by the Shenzhen Institute of Advanced Technology – part of the Chinese Academy of Sciences (CAS) – has fabricated a lithium-titanate battery with 110 milliamp hours per gram of specific capacity and a discharge voltage of 3 V, as well as a charge rate capability of up to 10 C and 100% capacity retention after 700 cycles. According to CAS, this places it among the best dual-ion batteries reported in literature.
The battery comprises a lithium titanate anode and a graphite cathode, but the researchers did not provide details of the electrolyte material.
Lithium titanate batteries present one of many pathways to eliminating rare, expensive and environmentally damaging materials, particularly cobalt and nickel, from the energy storage supply chain.
CAS noted that such batteries have thus far been limited by mismatching properties of the anode and cathode, and has sought to overcome these issues by using a 3D porous structure and implanting carbon nanofilms into their device. These were integrated via a range of novel processes, including molecule coupling, freeze drying, and pyrolysis.
The scientists describe their approach in “In-situ implanted carbon nanofilms into lithium titanate with 3D porous structure as fast kinetics anode for high-performance dual-ion battery“, which was recently published in Chemical Engineering. The group says that the porous structure dramatically enhanced the battery’s Li-ion diffusion coefficient, while the dual-ion configuration took advantage of faster kinetics to improve specific capacity.
CAS says that the device developed in Shenzhen is among the best-performing full batteries relying on the lithium-titanate chemistry. The academy plans to continue working in this area, as it shows great potential for highly safe and environmentally friendly energy storage applications.