Effects of Fluorine and Chromium Doping on the performance of Lithium-Rich Li 1+x MO 2 (M = Ni, Mn, Co) Positive Electrodes

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1 Effects of Fluorine and Chromium Doping on the performance of Lithium-Rich Li 1+x MO 2 (M = Ni, Mn, Co) Positive Electrodes Wei Kong Pang, 1,2 Hsiu-Fen Lin, 3 Vanessa K. Peterson, 1,2* Cheng-Zhang Lu, 4 Chia-Erh Liu, 4 Shih-Chieh Liao, 4 Jin-Ming Chen 4 1 Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia. 2 Institute for Superconducting & Electronic Materials, Faculty of Engineering, University of Wollongong, NSW 2522, Australia. 3 Department of Materials Science and Engineering, National Formosa University, Yunlin County 63201, Taiwan. 4 Department of Energy Nanomaterials, Material & Chemical Research Laboratory, Industrial Technology Research Institute, Taiwan. *Corresponding author. Supporting Information Figure S1. Preliminary electrochemical test results for 1, 2, and 3% Cr-doped LNCM (initial irreversibility of 79.2, 46.3, and mah/g, respectively) and for 5, 7.5, and 10% F-doped LNCM (capacity of 195.3, 186.0, and mah/g at 1 C, respectively).

2 Figure S2. SEM micrographs of (a) pristine, (b) Cr-doped, and (c) F-doped LNCM particles. Figure S3. XRPD data of pristine, Cr-doped, and F-doped LNCM.

3 Figure S4. NPD data of the LNCM sample with reflections arising from the layered phase indexed in black and those from the monoclinic phase in red. Figure S5. NPD data of the LNCM sample (black) and the contribution to the final refinement profile arising from the layered LiMO 2 and monoclinic Li 2 MnO 3 phases shown in red and blue, respectively. Li 2 MnO 3 reflections that are not overlapped by LiMO 2 reflections are identified by a blue asterisk.

4 Figure S6. Results of single-peak fitting of the LTO 222 reflection in NPD data of LNCM containing batteries. Figure S7. The rate of change of the LiMO reflection position in NPD data of batteries containing F and Cr doped as well as undoped LNCM during battery discharge from 2.6 V (vs. LTO). Fit results are shown alongside.

5 Figure S8. Simulated neutron powder diffraction patterns (at 2.41 Å) of the layered LiMO 2 phase with Cr at the transition metal 3a site (black) and the Li 3b site (red). The integrated area of the LiMO reflection with Cr at the metal and Li site are 3554(2) and 3453(2), respectively. Similarly, the LiMO reflection intensity with Cr at the transition metal and Li site is 14207(18) and 14175(18), respectively. Inset shows the LiMO reflection offset by 0.5 in 2θ for clarity.

6 Figure S9. LiMO reflection integrated intensity (red) as a function of z (blue, line is a guide to the eye) obtained by Gaussian peak fitting for (a) pristine, (b) Cr-doped, and (c) F-doped LNCM.

7 Table S1. Crystallographic details of Li 2 MnO 3 in (top) pristine, (middle) Cr-doped, and (bottom) F-doped LNCM obtained from Rietveld refinement against NPD data. Pristine LNCM: Li 2 MnO 3 phase with space group C2/m Lattice parameter a = 4.952(5) Å, b = 8.572(2) Å, c = 5.034(4) Å, beta = (4), Volume = (6) Å 3 Atom Site x y z Isotropic atomic displacement parameter U iso (Å 2 ) Site occupancy factor Li 2b 0 1/ (1)* 0.99 Mn 2b 0 1/ (1)* 0.01 Li 2c 0 0 1/ (1)* 1 Li 4h / (1)* 1 Mn 4g (1)* 1 O 4i 0.226(3) (2) 0.005(1)* 1 O 8j 0.282(2) 0.309(1) 0.255(2) 0.005(1)* 1 * constrained to be the same. Cr-LNCM: Li 2 MnO 3 phase with space group C2/m Lattice parameter a = 4.956(3) Å, b = 8.575(4) Å, c = 5.038(5) Å, beta = (6), Volume = (7) Å 3 Atom Site x y z Isotropic atomic displacement parameter U iso (Å 2 ) Site occupancy factor Li 2b 0 1/ (1)* 0.99 Mn 2b 0 1/ (1)* 0.01 Li 2c 0 0 1/ (1)* 1 Li 4h / (1)* 1 Mn 4g (1)* 1 O 4i 0.224(5) (5) 0.002(1)* 1 O 8j 0.253(4) 0.323(1) 0.227(3) 0.002(1)* 1 * constrained to be the same. F-LNCM: Li 2 MnO 3 phase with space group: C2/m Lattice parameter a = 4.974(9) Å, b = 8.571(3) Å, c = 5.02(1) Å, beta = (7), Volume = (8) Å 3 Atom Site x y z Isotropic atomic displacement parameter U iso (Å 2 ) Site occupancy factor Li 2b 0 1/ (1)* 0.99 Mn 2b 0 1/ (1)* 0.01 Li 2c 0 0 1/ (1)* 1 Li 4h / (1)* 1 Mn 4g (1)* 1 O 4i 0.208(5) (5) 0.001(1)* 1 O 8j 0.280(3) 0.310(1) 0.236(3) 0.001(1)* 1 * constrained to be the same.

8 Table S2. Redox centers in samples from ICP-AES assuming a negligible contribution of Co 3+ /Co 4+ to capacity. Samples Active wt.% Inactive Ni Mn Co Cr Active (%) LNCM Cr-LNCM F-LNCM Table S3. Coulombic efficiency of (a) LNCM, (b) Cr-LNCM, and (c) F-LNCM electrodes within type full batteries with LTO as the counter electrode. LNCM charge discharge coulombic efficiency Cr-LNCM charge discharge coulombic efficiency F-LNCM charge discharge coulombic efficiency