Binder-free hybrid Li4Ti5O12 anode for high performance lithium-ion batteries

Highlights: • A new binder-free hybrid anode material for lithium-ion batteries is developed. • The spinel LTO particles are coated by in-situ polymerization of styrenesulfonate. • The hybrid anode has significantly improved electrochemical performance. We have developed a new binder-free hybrid anode material for lithium-ion batteries, by directly coating spinel Li₄Ti₅O₁₂ particles using in-situ polymerization of styrenesulfonate (SS) to form a core-shell structure. The resulting hybrid anode has significantly improved electrochemical performance, with higher reversible capacity, rate-capability, and capacity value compared with pure Li₄Ti₅O₁₂. Of the initial discharge capacity of 239.2 mAh g⁻¹, 95.6% was retained after 100 cycles at 0.1 C-rate. The high cycle performance with increased discharge capacity is attributed to the coated poly (styrenesulfonate) (PSS) shell, which takes part in lithium ion storage and prevents the growth of a solid electrolyte interface (SEI) layer. The fast electron transfer in PSS also allows high rate-capability. Moreover, we clarify the contribution of carbon conductor in the range of 0.01 V–1.0 V.