LTO-TNO Core-Shell Composite for Fast-Charging Battery Anodes

The patent creates a core-shell composite material where lithium titanate forms the core and titanium niobate forms the shell. This composite structure allows the inner core to provide high conductivity and fast charge-discharge capability, while the outer shell contributes high theoretical capacity. The intimate contact between the two materials in the core-shell structure ensures efficient electron and ion transport pathways, resolving the conductivity mismatch issue that plagues simple mixtures.

The patent applies different material properties to different regions of the composite structure. The core region is designed with lithium titanate for high conductivity and fast kinetics, while the shell region uses titanium niobate for high capacity. This spatial differentiation of material functions allows each component to contribute its strengths while working together synergistically, achieving both fast charging and high energy density.

The patent combines titanium niobate (high capacity) with lithium titanate (high conductivity) in a core-shell structure. The titanium niobate shell provides the high theoretical capacity (387 mAh/g) while the lithium titanate core provides excellent electrical and ion conductivity. This composite approach allows the system to achieve both high capacity and fast rate performance, as electrons and lithium ions can efficiently transport through the conductive core while the capacity-rich shell contributes to energy storage.

The lithium titanate core acts as an intermediary that facilitates electron and ion transport between the external circuit and the titanium niobate shell. Due to its superior conductivity, the core serves as a高效的传输通道, allowing the low-conductivity titanium niobate to still achieve fast charge-discharge rates by relying on the core's transport capabilities.

The patent creates a core-shell composite where lithium titanate (fast kinetics) forms the core and titanium niobate (high capacity) forms the shell. This structure allows the system to achieve both fast charging/discharging rates (inherited from the lithium titanate core) and high energy density (contributed by the titanium niobate shell with 387 mAh/g theoretical capacity).

The patent segments the composite material into two functional regions: the core region optimized for fast electron and ion transport, and the shell region optimized for high capacity storage. This segmentation allows each component to specialize in its strength, with the core handling kinetics and the shell handling capacity, achieving overall optimization of both rate performance and energy density.

The patent applies titanium niobate only to the shell region rather than using it as the bulk material. This localized application allows the system to benefit from the high capacity of titanium niobate where it is most needed (at the interface with the electrolyte and for capacity contribution) while minimizing the amount of expensive material used. The core can be made from more cost-effective lithium titanate, reducing overall manufacturing costs while maintaining high performance.

The core-shell composite structure allows the patent to combine a high-capacity but expensive material (titanium niobate) with a more cost-effective material (lithium titanate). By strategically positioning the expensive material as a thin shell rather than the bulk component, the system achieves high theoretical capacity while controlling material costs, improving market competitiveness.