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Depth resolution and probing depth for Li in lithium thin film batteries achievable using different ion beam analytical techniques were investigated. Experiments using protons for nuclear reaction analysis, He ions for time-of-flight (TOF) energy elastic recoil detection analysis (ERDA) in transmission geometry, as well as He and Li ions for coincidence ERDA in transmission geometry are performed. Experimental results are compared in terms of the obtained Li concentration in the separator layer. In coincidence ERDA experiments, significant loss of Li-Li and He-Li coincidence counts was observed due to multiple scattering of recoiled/scattered particles in the battery sample. The ideal achievable Li depth resolution was calculated for the ion beam techniques. A depth resolution of 750, 1030, 310, and 510 x 10(15) atoms/cm(2) could be achieved in the Nb2O5 cathode by nuclear reaction analysis (NRA) using 2 MeV H, TOF-ERDA using 8 MeV He, and coincidence ERDA using 8 MeV He and 8 MeV Li ions, respectively, upon optimization of the experimental setup. While a depth resolution of 120 x 10(15) ions/cm(2) could be achieved for Li by conventional TOF-ERDA using an solid-state detector energy detector and light primary ions such as O under gracing incidence, TOF-ERDA experiments are found to produce significantly higher beam damage in batteries than other techniques. The beam damage in NRA and coincidence ERDA as performed in this study is estimated to be of the order of 10(-4) dpa. (C)& nbsp;2021 Author(s).& nbsp; All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/).

Thin-film batteries often contain oxides in the anode, cathode, and electrolyte materials. In-operando methods capable of Li and O depth profiling are relevant for battery research to study, e.g. diffusion and trapping of constituents. Here, we demonstrate ion beam-based analytical methods with high depth resolution and sensitivity for depth profiling Li and O in thin-film batteries using 10 MeV Li and He ions. Simultaneous depth profiling of Li and O was performed using combined coincidence elastic recoil detection analysis and Rutherford backscattering spectrometry measurements in the battery with 8 MeV He ions, and the Li and O transport was measured in operando. Reversible Li transport was observed from the LMO anode to the NbO cathode on charging and vice versa during discharging. O transport was observed from the LMO anode to the NbO cathode on first charging with 3.5 V but was not observed on further charging and discharging of the battery. Our in-operando measurements allow direct and quantitative observation of Li and O transport during charge-discharge cycles for thin-film batteries.

A quantitative assessment of Li transport is decisive for Li ion battery research. Here, we demonstrate in situ and in-operando depth profiling of the Li-inventory in lithium thin film batteries. We employ non-destructive coincidence elastic recoil detection analysis using different projectile ions in the MeV range to simultaneously quantify the lithium depth distribution in the whole stack with resolution better than 50nm by simulations of experimental data. Experiments were performed while charging and discharging the stack. 5MeV Li-7 primary ions were employed to extract the Li depth distribution in an similar to 3.6 mu m thick Ti/LMO/LIPON/NbO/Ti thin film battery. To show the versatility of the approach, a coincidence experiment was also performed using 4MeV He ions for an similar to 3.4 mu m thick Ti/LMO/LIPON/NbO/Ti battery. Our results illustrate, for example, lithium accumulation in the 90nm thick NbO layer upon charging with +3V. We could also show the transport of large amounts of Li from the LMO/LIPON interface to the LIPON/NbO interface upon overcharging with +5V. Altogether, these experiments demonstrate the potential of the employed technique, enabling in-operando high resolution composition depth profiling of Li and other light elements (e.g., H, He, C, N, and O) in ultrathin all-solid state batteries.

A whispering-gallery-mode (WGM) dye laser in blue, green, and orange regions is reported using dye-doped, solid, small spheres. A WGM dye laser is pumped by a transversely excited atmospheric UV N2 laser. Some features of the WGM dye laser are demonstrated.

A simple and inexpensive system is reported for a whispering-gallery-mode (WGM) laser using a dye-doped solid small sphere. A WGM laser is pumped by a compact transversely excited atmospheric (TEA) UV N2 laser. Experiments using the inexpensive system and some features in the WGM laser are demonstrated.

Mixed-dye-doped solid microspheres are excited by a transversely excited-atmospheric ultraviolet N2 laser to obtain a multiple oscillation of a whispering-gallery-mode (WGM) dye laser in both green and orange regions. The multiple oscillation exhibits separate modes of WGMs in both spectral regions.