Layer-by-layer printing of multi-layered heterostructures using Li4Ti5O12 and Si for high power Li-ion storage

Abstract

Heterogeneous, multi-layered electrodes based on high power Li 4 Ti 5 O 12 interleaved with a smaller fraction of high capacity Si were fabricated using layer-by-layer spray printing, with the goal of achieving a balance of power and capacity for Li-ion storage technologies. The faradaic charge/discharge behavior of the multi-layered hybrid electrodes was investigated as a function of (i) the thickness of the discrete Si layer within the multilayered electrode, and (ii) the location of the Si layer within the electrode: on the top of the Li 4 Ti 5 O 12 (closest to the separator), between two layers of Li 4 Ti 5 O 12 (sandwich configuration) or at the Li 4 Ti 5 O 12 base (next to the current collector but furthest from the separator). The optimum arrangement of Si spray printed on Li 4 Ti 5 O 12 offered outstanding electrochemical performance at high current densities of 4000 mA/g and after 500 cycles when in a full Li-ion battery configuration coupled with a spray printed LiFePO 4 cathode. The optimized multilayered electrode was reliably reproduced as a double-sided coating over large area current collectors (≥20 cm × 15 cm). Sprayed printed electrodes were also readily patterned in-plane as well as through-thickness, offering the prospect for selective additions of high capacity Si or other active or inactive electrode components at specific locations to provide new Li-ion battery performance characteristics.

Low-tortuosity and graded lithium ion battery cathodes by ice templating

“…Electrode slurries were prepared by homogeneously mixing the LFP powders, Super P carbon black (Alfa Aesar) and sodium carboxymethyl cellulose (CMC, Sigma Aldrich) binder in a weight ratio of 90 : 5 : 5 in deionized water. [64][65][66] For fabricating the electrodes by DIT, the slurry was directionally frozen in a custom-made 3D printed acrylonitrile butadiene styrene (ABS) mould on a copper cold nger, one end of which was immersed in liquid nitrogen. Freezing at atmosphere pressure (101 kPa) involved cooling from room temperature to À10 C until fully solid.…”

Scalable Multilayer Printing of Graphene Interfacial Layers for Ultrahigh Power Lithium‐Ion Storage

“…The arrangement of G and LTO layers in the multilayered structure is tailored simply by switching between G or LTO containing feedstock suspensions during deposition. This freedom in design for discrete layers and various types of grading [23][24][25][26][27][28][29] is not available by conventional slurry casting manufacture of LIB and LIC electrodes, and was investigated to obtain more attractive balance of overall LIC performance.…”

Ultrathin [110]‐Confined Li4Ti5O12 Nanoflakes for High Rate Lithium Storage

“…[ 10 ] On the other hand, LTO has excellent reversibility and ultrahigh structural stability during lithium insertion/extraction, ensured by the zero‐strain property of the material. [ 11,12 ] These features make it a promising candidate for high‐rate energy storage, in which long cycle life, high safety, and high power density are highly desired. [ 13 ] Despite the former two requirements are well met for LTO, the achievement of the latter is hindered by its moderate ionic diffusivity (≈10 –9 to 10 –13 cm 2 s –1 ) and low electrical conductivity (≈10 –13 S cm –1 ).…”