jz9b02014_si_001.pdf (266.59 kB)
Lithium Diffusion in Copper
journal contribution
posted on 2019-08-23, 14:38 authored by Rico Rupp, Bart Caerts, André Vantomme, Jan Fransaer, Alexandru VladCopper
is the conventional, broadly applied anode current collector
in lithium-ion batteries, because Li does not form intermetallic alloys
with Cu at room temperature. Fast diffusion and trapping of lithium
in copper were, however, suggested in the past, and the involved diffusion
mechanisms are still not clarified. By using three complementary methods,
we determine grain boundary and lattice diffusion of lithium in copper.
We show that indiffusion into copper is possible not only from metallic
lithium deposits at the surface but also from a Li+-containing
electrolyte. Lattice diffusion (D0 = 3.9
× 10–9 cm2/s; Ea = 0.68 eV) and grain boundary diffusion (D0 = 1.5 × 10–11 cm2/s; Ea = 0.36 eV) are found to be 13 orders of magnitude
lower than previously published. Furthermore, for practical Li-ion
battery considerations, lithium trapping in copper current collectors,
which relies heavily on operating temperature and morphology, is discussed.