High performance thick cathodes enabled by gradient porosity

Aerosol Jet-Printed LFP Cathodes with Bimodal Pore Distribution Improve the Rate Capability of LIB Cells

“…The desirable electrode architecture of the calendered AJ cathode shown in Figure is similar to the porosity-engineered electrodes manufactured by other groups. ,− Notably, many of the proposed manufacturing techniques for achieving the porosity-engineered cathode require multiple steps, are difficult to scale, and may generate electrodes with low mechanical integrity . Additionally, volumetric energy density is typically sacrificed in favor of gravimetric energy density, which further limits the application of some of the previously demonstrated tailored electrodes .…”

Revisiting the promise of Bi-layer graded cathodes for improved Li-ion battery performance

“…Prior literature on microstructural bi-layer graded electrodes have not investigated capacity fade with long-term cycling. The reports have drawn conclusions on the superior cycling performance of graded electrodes over conventional electrodes based solely on initial discharge capacities and short-term cycling (~50 cycles) at low C-rate (0.1-0.5C) [16,19,23]. Previous simulation works on graded electrodes also predict their performance based on first discharge capacity and without incorporating CEI and mechanical effects [10,14,15,27].…”

“…Very few researchers have investigated graded electrodes through experiment to validate the simulation results [16][17][18][19][20][21][22][23]. Huang et al synthesized a thin (12.2µm) TiO 2 graded anode structure with two discrete layers fabricated by spray deposition [16].…”

“…Furthermore, EIS measurements on full cells confirmed a reduction in both film (R f ) and charge transfer (R ct ) resistance for the porosity-graded design. Very recently, Song et al manufactured a similar porosity graded LiNi 0.8 Co 0.15 Al 0.05 O 2 electrode by employing a combination of slurry casting and electrostatic spinning techniques [23]. This 145µm bi-layer cathode retained a ~35.6% and ~ 45.6% higher discharge capacity at 0.5C after 50 cycles compared to other electrodes fabricated by diverse approaches.…”

Gradient porosity electrodes for fast charging lithium-ion batteries

“…The varied porosities could enhance electrolyte inltration, reduce polarization and increase the use of active materials in the thick electrodes. 29,30 Despite the critical role of anodes in fast charge applications, most research on gradient porosity has been reported on cathodes 31,32 using small particles in the top layer and large particles in the bottom layer to construct a bi-layered electrode to improve rate capabilities. 33 However, it is unclear whether the improved rate performance is the result of the gradient porosity feature or the utilization of small particles.…”