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As an anode for lithium-ion batteries, metallic bismuth (Bi) can provide a superb volumetric capacity of 3800 mA h cm^–3, showing perspective value for application. It is a pity that the severe volume swelling during the lithiation process leads to the dramatic deterioration of the cycling performances. To overcome this issue, Bi nanorods encapsulated in N-doped carbon nanotubes (yolk–shell Bi@C–N) are elaborately designed through in situ thermal reduction of Bi₂S₃@polypyrrole nanorods. In comparison with the commercial Bi, the lithium storage capacities of Bi@C–N are significantly enhanced, and it presents a stable volumetric capacity of 1700 mA h cm^–3 over 500 cycles at a high current density of 1.0 A g^–1, nearly 2.2 times that of graphite. The N-doped carbon nanotube and the cavity between the carbon wall and Bi jointly contribute to this superior performance. Especially, the failure mechanism of Bi …