Interfacial Outgassing Transport and Phase Transformations during Sintering Cycles
Controlled sweep gas kinetics and balanced heating ramps prevent outgas entrapment, eliminating resistive rocksalt phase reconstruction in sintered cathodes.
LATP
Meaning
Lithium ion conducting ceramic material characterized by a NASICON crystal structure. Solid state batteries frequently utilize latp as an electrolyte because it offers high stability against moisture compared to sulfide alternatives. The material consists of lithium, aluminum, titanium, and phosphate arranged in a rigid framework.
Crystal Lattice
Octahedral and tetrahedral sites within the structure provide a path for rapid ion movement. Within latp, the substitution of aluminum for titanium increases the concentration of lithium ions and optimizes the lattice parameters for conduction. This arrangement creates a three dimensional network of channels that supports efficient battery charging.
Electrochemical Behavior
Resistance to oxidation at high voltages allows the use of cathode materials with superior energy density in solid state designs. Although latp possesses excellent ionic conductivity, its direct contact with lithium metal can cause a reduction reaction that increases internal resistance over time. Designers often place a thin buffer layer between the ceramic and the anode to prevent this degradation and extend the cycle life of the battery.
Processing Step
High temperature sintering is necessary to achieve the density required for a functional electrolyte separator. Producing latp in thin sheets requires precise control over the cooling rate to avoid thermal cracking. A fully dense ceramic pellet prevents the growth of lithium dendrites that would otherwise short the cell.