Customizable Nonplanar Printing of Lithium‐Ion Batteries

Abstract

widely used in consumer electronics due to the advantages of rechargeability and high energy density. [4][5][6] Commercial LIBs are usually fabricated in fixed geometry such as cylinder, coin, and pouch with scrolled or layered planar sheets for each component. [7] Nevertheless, LIBs with customizable geometry are desired for specialized applications such as wearable electronics [8,9] and on-device power systems [10,11] for automobile and aerospace vehicles, For example, LIBs can be made into a watchband to power an electronic watch, [12] which eliminates the installation and replacement of coin cell. To meet such demands, irregular, customizable LIBs in arbitrary geometry on 3D structures along with the packaging, integrating, and manufacturing approaches need to be developed. So far, the most effective solution to fabricate freeform LIBs is additive manufacturing (AM, popularly known as 3D printing). [13][14][15][16] The on-demand and layer-by-layer manufacturing method has provided the flexibility to accommodate customizable designs of 3D LIBs.Electrodes are the most essential components of LIBs. Currently reported AM processes for electrodes are mostly based on extrusion printing, [17][18][19][20][21][22][23][24] with a few reports on other ink-based printing methods including inkjet printing [25] and aerosol printing. [10] In extrusion printing, active material laden inks are directly deposited and powered by ultra-high air pressure. The materials are extruded into semi-solidified and self-supportive filaments owing to the shear-thinning characteristics of the highly viscous inks. Main advantage of AM processes is the capability of printing electrodes in arbitrary geometry. For example, Lacey et al. and Wang et al. demonstrated 3D printing of mesh and lattice structured electrodes, which effectively introduced macroporosity and facilitated the transportation of lithium-ions under high charging/discharging rate. [18,23] The flexibility in printed geometry also enables the fabrication of electrodes with high aspect ratio and high areal capacity, which are usually not processable by conventional slurry-casting method. Sun et al. first printed high aspect ratio, multilayer, interdigitated electrodes for micro-LIBs with high energy density and power density. [21] Despite these advantages, in extrusion-printing, composition and rheological behaviors of inks are demanding due to the requirements in clogging prevention, substrate bonding and shape maintenance. [19,20] Alternatively, aerosol printing Lithium-ion batteries (LIBs) are widely used in consumer electronics due to their rechargeability and high energy density. Commercial LIBs are fabricated in fixed geometries such as cylinder, coin, and pouch. However, for specialized applications such as wearable electronics and on-device power systems, customizable LIBs with arbitrary geometry on threedimensional (3D) structures need to be developed. For this purpose, aerosol printing is uniquely suitable due to its flexible working distance, allowing deposition on nonp...

Additive Manufacturing of Electrochemical Energy Storage Systems Electrodes

“…[125] In addition, Yu et al analyzed aerosol-printed 3D electrodes on nonplanar substrates. [126] When used as a full cell, the customized LFP cathode and LTO anode exhibited a maximum aerial capacity of 7.1 mAh cm À2 with 78.4% capacity retention after 30 cycles of cell operation, all of which attributed to the nonplanar geometry and electrode thickness, as shown in Figure 3a-l. [126] Although carbon-based and noncarbon-based 3D electrodes (synthesized and 3D printed) have shown considerable promise due to their cycling stability and elevated specific capacities by synergistically combining various precursor materials, factors such as synthesis parameters, electrode geometry, and cost still must be optimized for these electrodes to gain greater prominence. [127,128]…”

“…a,b) Images of the aerosol-printed LFP cathode,c,d) similar images of the aerosol-printed LTO anodes, e,f ) SEM micrograph demonstrating the characteristic bulk microstructure of the LFP cathode and LTO anode, respectively, g) schematic representation of the multilayer printing process, h,i) SEM images of the 4-layered and 8-layered aerosol-printed LFP cathode, j) actual photograph of the nonplanar cell lighting a LED light, k) characteristic galvanostatic charge-discharge curves of the nonplanar and planar electrode cell, l) Specific capacity and Coulombic efficiency variation over 30 cycles, for the LFP cathode half-cell. Reproduced with permission [126]. Copyright 2019, Wiley-VCH GmbH.…”

3D Printed Micro‐Electrochemical Energy Storage Devices: From Design to Integration

“…Besides, the good bonding of packages and their encapsulated electrodes and collectors helps dissipate stress/strain in the devices, further providing better mechanical properties. [ 212 ] However, package printing is still in its infant stage. The following section briefly summarizes some recent representative reports on 3D‐printed packaging.…”

“…d) Schematics of FDM printed planar and non-planar enclosures. Reproduced with permission [212]. Copyright 2019, Wiley.…”

Additive Manufacturing of Sandwich–Structured Conductors for Applications in Flexible and Stretchable Electronics

“…Currently, conventional microfabrication methods are playing a dominant role in the manufacturing of these devices, which involve expensive vacuum-based deposition and time-consuming subtractive etching processes. [9,10] As alternatives, additive printing techniques such as inkjet printing, [11,12] aerosol printing, [13][14][15][16] and electrohydrodynamic printing [17,18] with atmospheric-processing capabilities have shown great potentials in the future direction toward the low-cost and largescale manufacturing of flexible and stretchable electronics.…”