Fig. 2. (a) The in situ magnetic responses of the Co/C NPs anode at an applied magnetic field of 3 tesla to the second and third cycles at a current density of 0.1 A g−1 between 0.01–3.0 V (vs. Li/Li+). A schematic of the spin-polarized density of states at the surface of ferromagnetic metallic Co grains (b) before and (c) after electron filling into the spin-down d band.
