An ultrafast synthesis method of LiNi_1/3Co_1/3Mn_1/3O₂ cathodes by flash/field‐assisted sintering

Abstract

LiNi1/3Co1/3Mn1/3O2 as a promising cathode material in lithium‐ion batteries was synthesized by flash/field‐assisted sintering technique for the first time. This study showed that the current‐limited synthesis of LiNi1/3Co1/3Mn1/3O2 could be carried out at temperatures less than 400°C for only 8 minutes, compared with the conventional pressureless sintering at 850°C for 12 hours. X‐ray diffraction results showed the phase evolution from precursor mixtures to the final LiNi1/3Co1/3Mn1/3O2 products during flash/field‐assisted sintering process and a well‐layered structure without undesirable cation mixing in the as‐formed LiNi1/3Co1/3Mn1/3O2. Combined with the lowered sintering temperatures and reduced sintering time, the excellent electrochemical performance of flash/field‐assisted sintered LiNi1/3Co1/3Mn1/3O2 materials suggested that this technique could be an energy‐efficient approach for the synthesis of lithium‐ion battery cathode materials and other materials requiring high‐temperature heat treatment.

Solid‐State Li–Metal Batteries: Challenges and Horizons of Oxide and Sulfide Solid Electrolytes and Their Interfaces

“…[178] Other than classical solidstate sintering approach, several nonequilibrium densification processes that use artificial or chemically induced pressure as alternative sinter driving force to the temperature. These processes can overcome thermodynamic instability, second-phase formation and Li loss, including high-pressure field assisted sintering technique (FAST), also known as spark plasma sintering (SPS), [184] flash sintering and aerosol deposition methods for thin-film (1-10 µm) fabrication. For example, highly dense oxide electrolytes, [185,186] electrolyte-electrode composite [187] can be prepared with significantly lowered the sintering temperature and time.…”

Reactive Flash Sintering of Ceramics: A Review

“…The application of RFS for producing Li‐ion conductors was first studied on the synthesis of LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NMC), a cathode material for Li‐ion batteries. [ 63 ] Under an electric field, the production of NMC was achieved at a furnace temperature below 400 °C in 8 min, contrasting the conventional synthesis at 850 °C for 12 h. In the study, the objective was to develop a time‐saving and cost‐effective synthesis technique for industrial demands. The authors claimed that the flashed‐processed NMC attained a higher degree of crystallinity that formed a better‐layered structure and improved its electrochemical performance.…”

“…[ 46 ] It is important to mention that RFSed samples can present near full density; [ 46,52,58 ] however, many studies verified moderate densities or their densities are not reported (see Table 1 and 2). [ 63,68,72,76 ]…”

“…In fact, owing to its recent discovery, most of the studies regarding RFS are related to materials processing optimization. [55][56][57][58]63,64,68,94] Nonetheless, it is reasonable to assume that FS and RFS share similar mechanisms. The underlying physical mechanisms of rapid densification achieved during FS have been discussed in comprehensive reviews [16,[40][41][42] and can be extended to RFS.…”

“…[46] It is important to mention that RFSed samples can present near full density; [46,52,58] however, many studies verified moderate densities or their densities are not reported (see Table 1 and 2). [63,68,72,76] The enhanced diffusion observed for both reactions/crystallizations and densification may be improved by different effects during RFS. Possible mechanisms of RFS are presented here; it should be noticed that more than one of these mechanisms may be participating in an RFS experiment, while different effects can be activated depending on the processing parameters and the material being tested.…”