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A standardless method for the determination of nanometric thicknesses has been developed to the morphological characterization of anodes of lithium-ion batteries, particularly for those based on binder free Si/C binary composites generated by sputtering deposition. The procedure was developed on the basis of the detection of characteristic x rays under electron impact, and although it was specifically designed for nano-stratified samples consisting of a Si film deposited onto a C layer (which in turn is deposited on a Cu substrate), it is also easily applicable to other configurations. Because it is necessary to know the thickness of the surface layer to obtain the thickness of the deepest layer, the calculations involve the application of an iterative strategy based on Monte Carlo simulations. The validation of the method was done on a set of samples whose thicknesses were also determined by Rutherford backscattering spectroscopy (RBS), and the method was applied to another set of anodes, which gave results that coincided with the expected values. The thicknesses of the Si and C layers of the binder free composite anode obtained by the proposed method were used to calculate the specific capacity. Galvanostatic charge-discharge curves up to 100 cycles were analyzed for three different C/Si ratio anodes, and the experimental results were compared with the theoretical capacity for each binary system.In Figure 1 a particular application example of the developed method is presented. The analyzed samples were prepared by sputtering deposition of three different thicknesses of C onto Cu foils followed by a deposition of a silicon film. The implementation of the method allowed a thickness estimation of 25 nm for Si, and 92, 156 and 190 nm for C. These values where used to obtain the mass ratio of the anode and a corresponding theoretical specific capacity. Afterwards, the anodes were mounted as working electrodes in an electrochemical cell with lithium as counter electrode and cycled 100 times at a constant current of 20 A. In Figure 2 it is shown, as an example, the cycling response for the electrode Si25/C92 and the corresponding theoretical capacity, 1098 mAhg-1, calculated as a reference. The electrochemical test shows that the experimental specific capacity of the particular anode is 1200 mAhg-1, in good agreement with the estimation made by the present method. The nano-stratified Si/C anodes prepared by sputtering deposition showed good cycling performance and great stability regarding the silicon volume expansion during the charge-discharge process.