Pulsed-Laser-Deposited LiMn 2 O 4 Thin-Film Solid-State Microbatteries with Extended Voltage Window Cycling
Year: 2026
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Thin-film microbatteries provide on-chip and surface-mount energy storage for Si-based microsystems, where device area is the primary constraint. Commercial implementations, available for more than 20 years, have largely relied on LiCoO 2 cathodes because they are straightforward to process and package. LiMn 2 O 4 offers a cobalt-free alternative; however, in conventional liquid-electrolyte Li-ion cells, its use is constrained by Mn dissolution and capacity fade, especially when the voltage window is widened to access its theoretical capacity of ∼119 μAh·cm –2 ·μm –1 (∼296 mAh·g –1 ). Thin-film solid-state architectures can mitigate these limitations and are naturally aligned with footprint-limited applications, where areal capacity and areal energy are the relevant figures of merit. The focus of this study is to examine the device behavior of LiMn 2 O 4 thin-film microbatteries operated in a wider voltage window, using a LiPON solid electrolyte and a Li metal anode. Polycrystalline LiMn 2 O 4 cathodes (∼850 nm) were grown by pulsed laser deposition with sequential Li 2 O enrichment during growth. X-ray diffraction, Raman features, and depth-profiling glow discharge optical emission spectroscopy are consistent with the presence of a Li-rich spinel component formed during deposition. The resulting LiMn 2 O 4 /LiPON/Li cells, cycled between 2.0 and 4.5 V, deliver up to ∼50 μAh·cm –2 at low rates; at higher rates, the wider window enables capacities up to ∼4 times those obtained on the same devices in the conventional 3.5–4.5 V window. Impedance measurements are used to track evolution during conditioning and operation. Finally, we provide an overview of relevant LiMn 2 O 4 solid-state thin-film microbatteries and outline a tentative route to stabilize the LiMn 2 O 4 /LiPON interface under wider-window operation.
Source: ACS Applied Energy Materials
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Funders: Ministerio de Ciencia, Innovación y Universidades, Centres de Recerca de Catalunya, European Commission, Generalitat de Catalunya, Eidgenössische Materialprüfungs- und Forschungsanstalt, Horizon 2020 Framework Programme, Bundesamt für Energie, Agencia Estatal de Investigación, European Social Fund, Direcció General de Recerca, Generalitat de Catalunya, NextGenerationEU
Awards: G1170553378, G1175115578, G1181246830, G1412748244, G2064873908, G210041235, G2262748287, G24120701, G2462415295, G2601397997, G294895050, G2969159057, G3005324705, G300979063, G34346518, G3480869486, G3546882995, G3681454997, G4042783231, G4228227490, G4250691832, G425668148, G4442677895, G4526231891, G5080475149, G5143056060, G5195188938, G5743488360, G5835046774, G6623938765, G6656126374, G69051668, G7084143925, G7369074228, G787121397, G8406619813, G8522095481, G8637226926, G924277865
OpenAlex ID: W7138177371