Rechargeable magnesium (Mg) batteries (RMBs) are potential candidates for new generation battery technologies due to the attractive properties of Mg as a metal anode, especially the intrinsic nature of homogeneous Mg deposition and abundant Mg reserves. Compared to the monovalent counterpart (e.g. Li⁺), the divalent Mg ions have a greater charge density and thus need to overcome much stronger electrostatic forces for insertion and diffusion inside the host structures. One of the strategies to enhance Mg²⁺ ion intercalation kinetics is to reduce its charge density. Herein, we present the intercalation chemistry of the solvated ions [Mg(DME)₃]²⁺, in which the improved ion mobility has been proven by various electrochemical and spectroscopic characterizations.¹ The novel concept was realized with Mg[B(hfip)₄]₂/DME electrolyte^{2, 3} and a layered MoS₂ cathode coupled with a Mg anode. The cell configuration exhibited a long-term cycling stability (>200 cycles) and high rate capability (47 mA h g^-1 at 0.5 A g^-1). In addition, the mechanism of Mg storage has been investigated in detail, revealing the reversible 2H to 1T MoS₂ phase transition during Mg ions de-/intercalation. Compared to other reported intercalation with [Mg(H₂O)_x]²⁺ or MgCl^-,^{4, 5} the DME molecules will neither passivate the anode nor corrode the cell components, which makes this approach more practical. Moreover, the concept of solvated Mg²⁺ ions can be potentially extended to other intercalation cathode materials and applied to other multivalent ions intercalation. References Z. Li, X. Mu, Z. Zhao-Karger, T. Diemant, R. J. Behm, C. Kübel and M. Fichtner, Nature Communications, 2018, 9, 5115. Z. Zhao-Karger, M. E. Gil Bardaji, O. Fuhr and M. Fichtner, J. Mater. Chem. A, 2017, 5, 10815-10820. Z. Zhao-Karger, R. Liu, W. Dai, Z. Li, T. Diemant, B. P. Vinayan, C. Bonatto Minella, X. Yu, A. Manthiram, R. J. Behm, M. Ruben and M. Fichtner, ACS Energy Letters, 2018, 3, 2005-2013. K. W. Nam, S. Kim, S. Lee, M. Salama, I. Shterenberg, Y. Gofer, J.-S. Kim, E. Yang, C. S. Park, J.-S. Kim, S.-S. Lee, W.-S. Chang, S.-G. Doo, Y. N. Jo, Y. Jung, D. Aurbach and J. W. Choi, Nano Letters, 2015, 15, 4071-4079. H. D. Yoo, Y. Liang, H. Dong, J. Lin, H. Wang, Y. Liu, L. Ma, T. Wu, Y. Li, Q. Ru, Y. Jing, Q. An, W. Zhou, J. Guo, J. Lu, S. T. Pantelides, X. Qian and Y. Yao, Nature Communications, 2017, 8, 339.