These datasets are for the four-dimensional scanning transmission electron microscopy (4D-STEM) and electron energy loss spectroscopy (EELS) experiments for cathode nanoparticles at different states. The raw 4D-STEM experiment datasets were collected by TEM image & analysis software (FEI) and were saved as SER files. The raw 4D-STEM datasets of SER files can be opened and viewed in MATLAB using our analysis software package of imToolBox available at https://github.com/flysteven/imToolBox. The raw EELS datasets were collected by DigitalMicrograph software and were saved as DM4 files. The raw EELS datasets can be opened and viewed in DigitalMicrograph software or using our analysis codes available at https://github.com/chenlabUIUC/OrientedPhaseDomain. All the datasets are from the work "Nanoscale Stacking Fault Engineering and Mapping in Spinel Oxides for Reversible Multivalent Ion Insertion" (2024).

The 4D-STEM experiment data include four example datasets for cathode nanoparticles collected at pristine and discharged states. Each dataset contains a stack of diffraction patterns collected at different probe positions scanned across the cathode nanoparticle.
1. Pristine untreated nanoparticle: "Pristine U-NP.ser"
2. Pristine 200ºC heated nanoparticle: "Pristine H200-NP.ser"
3. Untreated nanoparticle after first discharge in Zn-ion batteries: "Discharged U-NP.ser"
4. 200ºC heated nanoparticle after first discharge in Zn-ion batteries: "Discharged H200-NP.ser"

The EELS experiment data includes six example datasets for cathode nanoparticles collected at different states (in "EELS datasets.zip") as described below. Each EELS dataset contains the zero-loss and core-loss EELS spectra collected at different probe positions scanned across the cathode nanoparticle.
1. Pristine untreated nanoparticle: "Pristine U-NP EELS.zip"
2. Pristine 200ºC heated nanoparticle: "Prisitne H200-NP EELS.zip"
3. Untreated nanoparticle after first discharge in Zn-ion batteries: "Discharged U-NP EELS.zip"
4. Untreated nanoparticle after first charge in Zn-ion batteries: "Charged U-NP EELS.zip"
5. 200ºC heated nanoparticle after first discharge in Zn-ion batteries: "Discharged H200-NP EELS.zip"
6. 200ºC heated nanoparticle after first charge in Zn-ion batteries: "Charged H200-NP EELS.zip"
The details of the software package and codes that can be used to analyze the 4D-STEM datasets and EELS datasets are available at: https://github.com/chenlabUIUC/OrientedPhaseDomain. Once our paper is formally published, we will update the relationship of these datasets with our paper.