Standardless determination of nanometric thicknesses in stratified Si/C anodes for lithium ion batteries by electron probe microanalysis

PEREYRA, G.D.; BUDINI, N.; OLIVA, F.Y.; MANUEL OTERO; PABLO PÉREZ; EZEQUIEL LEIVA; J. C. TRINCAVELLI

Belgrado

Congreso; 71st Annual Meeting of the International Society of Electrochemistry; 2020

A standardless method for the determination of nanometric thicknesseswas developed on the basis of the detection of characteristic x rays.The method was developed aiming to the morphological characterizationof anodes of lithium-ion batteries, particularly for those based onbinder free Si/C binary composites generated by sputteringdeposition. Even when the procedure was designed for this particularcase of nano-stratified samples consisting of a Si film depositedonto a C layer, which in turn is deposited on a Cu substrate, it iseasily extensible to other configurations. To obtain the thickness ofthe deepest layer it is necessary to know the thickness of thesurface layer. For this reason, the calculations involve an iterativestrategy based on Monte Carlo simulations. The method was validatedin a set of samples whose thicknesses were also determined by RBS. Inaddition, the method was applied to another set of anodes, givingresults that matched the expected values. The thickness determinationof the Si and C layers of the anode binder free composite was usedfor the specific capacity determination. Galvanostaticcharge-discharge curves up to 100 cycles were analyzed for threedifferent C/Si ratio anodes, and the experimental results werecompared with the theoretical capacity for each binary system.p { margin-bottom: 0.25cm; direction: ltr; color: #000000; line-height: 120%; orphans: 0; widows: 0 }p.western { font-family: "Times New Roman", serif; font-size: 10pt; so-language: en-US }p.cjk { font-family: "Times New Roman", serif; font-size: 10pt }p.ctl { font-family: "Times New Roman", serif; font-size: 10pt; so-language: ar-SA }