Ultrasonic Spray Deposition for Battery Materials Research

Most solid electrolytes reported in the literature — garnet-type LLZO (Li₇La₃Zr₂O₁₂), perovskite LLTO, NASICON-type LATP — began life as sintered pellets hundreds of microns thick, densified near 1,000 °C. Pellets are excellent model systems and poor products: too thick, too brittle, and too expensive to sinter at scale. A widely cited review in Nature Energy (Balaish et al., 2021) makes the case that up to 75% of projected SSB production costs may be an artifact of assuming classic sintering — and identifies wet-chemical film deposition, including spray pyrolysis, as a route to low-temperature, large-area, sinterless ceramic manufacture.

Spray pyrolysis earns its place on that list for concrete reasons:

• No vacuum chamber. Films deposit at atmospheric pressure onto a heated substrate, at a fraction of the capital cost of PVD.
• Scan speed. Spray setups traverse large areas at meters per minute, versus millimeters per second for dip coating — the throughput argument for manufacturing relevance.
• Solution-phase chemistry control. Multi-cation compositions and dopants are adjustments to the precursor bath, not new sputter targets. Lithium loss — the chronic headache of vacuum-deposited Li ceramics — is addressed by simply over-lithiating the precursor solution.
• The right thermal window. Lithium salts decompose between roughly 100 and 550 °C; heated-substrate spray pyrolysis operates natively in that range.

A spray pyrolysis film is only as good as the droplets it is built from. Ultrasonic atomization produces a narrow droplet-size distribution at very low spray velocity — droplets drift to the heated substrate rather than blasting it — which translates directly into the two properties battery film work demands:

Uniformity. Thin, even wet layers per pass, built up over multiple passes to a controlled final thickness anywhere from hundreds of nanometers to 20 µm and beyond.

Drying control. Fine droplets and gentle deposition reduce the drying stresses that crack wet-chemical ceramic films — a failure mode the SSB literature explicitly identifies as a processing bottleneck.

MicroSpray's high-temperature ultrasonic nozzle is designed for continuous operation with substrates and fixturing at up to 600 °C — purpose-built for spray pyrolysis of crystalline oxide films. The low-flow, non-clogging ultrasonic design tolerates concentrated, particle-laden, and sol–gel precursors, and the nozzle installs as a standalone component in your own rig: glovebox-adjacent enclosures, inert-gas purged chambers for moisture-sensitive lithium chemistry, custom motion systems, or roll-to-roll fixtures. We supply the atomization; you keep control of the process.