11 Lithium-Ion Battery—3D Micro-/Nano-Structuring, Modification …
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Fig. 11.2 Film adhesion of NMC on DLIP modified aluminum foils: SEM images of a DLIP
surface structure on aluminum ( = 1.3 μm), and b residual NMC-particles after 90° peel-off
testing. c residual NMC-particles after 90° peel-off testing using an untreated aluminum foil
1064 nm. A line periodicity of 1.3 μm with an average surface roughness Ra of
109 nm could be measured by atomic force microscopy (AFM). Tape casting of
composite material made of lithium nickel manganese cobalt oxide was performed
using structured and unstructured aluminum foils as substrate. The film adhesion
was characterized by 90° peel-off tests as described elsewhere [49]. A significant
increase of adhesion of about 250 N/m could be detected on aluminium surface.
The reference value for unstructured aluminum was 140 N/m. After the peel-off
tests, the NMC-particles and binder were tightly stuck on the modified aluminum
surface (Fig. 11.2b). On contrary, the coating of the reference samples was almost
completely removed from the unstructured current collector surface (Fig. 11.2c),
which indicates, that the intrinsic film adhesion among the active particles is more
stable than the adhesion of the coating towards the unstructured surface.
The formation of LIPSS on copper current collectors (anode) was explored as
function of laser fluence, pulse number, and scanning speed for a laser pulse duration
of 350 fs and a laser wavelength of 515 nm. For single pulse laser ablation, the
copper surface was exposed to the laser beam at a fluence of 10.35 J/cm
2 (Fig. 11.3a).
Randomly distributed nano-pores and nano-sized ripples were formed on the surface.
Elemental analysis by using energy-dispersive X-ray spectroscopy revealed that no
oxide formation took place due to laser exposure. Well defined periodic ripples could
Fig. 11.3 SEM-images of ultrafast laser-induced nano-sized surface structures: a nano-pores,
b LIPSS, and c micro-structure combined with nano-ripples
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Fig. 11.2 Film adhesion of NMC on DLIP modified aluminum foils: SEM images of a DLIP
surface structure on aluminum ( = 1.3 μm), and b residual NMC-particles after 90° peel-off
testing. c residual NMC-particles after 90° peel-off testing using an untreated aluminum foil
1064 nm. A line periodicity of 1.3 μm with an average surface roughness Ra of
109 nm could be measured by atomic force microscopy (AFM). Tape casting of
composite material made of lithium nickel manganese cobalt oxide was performed
using structured and unstructured aluminum foils as substrate. The film adhesion
was characterized by 90° peel-off tests as described elsewhere [49]. A significant
increase of adhesion of about 250 N/m could be detected on aluminium surface.
The reference value for unstructured aluminum was 140 N/m. After the peel-off
tests, the NMC-particles and binder were tightly stuck on the modified aluminum
surface (Fig. 11.2b). On contrary, the coating of the reference samples was almost
completely removed from the unstructured current collector surface (Fig. 11.2c),
which indicates, that the intrinsic film adhesion among the active particles is more
stable than the adhesion of the coating towards the unstructured surface.
The formation of LIPSS on copper current collectors (anode) was explored as
function of laser fluence, pulse number, and scanning speed for a laser pulse duration
of 350 fs and a laser wavelength of 515 nm. For single pulse laser ablation, the
copper surface was exposed to the laser beam at a fluence of 10.35 J/cm
2 (Fig. 11.3a).
Randomly distributed nano-pores and nano-sized ripples were formed on the surface.
Elemental analysis by using energy-dispersive X-ray spectroscopy revealed that no
oxide formation took place due to laser exposure. Well defined periodic ripples could
Fig. 11.3 SEM-images of ultrafast laser-induced nano-sized surface structures: a nano-pores,
b LIPSS, and c micro-structure combined with nano-ripples