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In this work, we significantly improve the cyclability of Mn3O4 anodes in Li‐ion batteries by enhancing its intra‐particle electronic conductivity by doping with Na. Na was selected because, unlike typical transition metal dopants, it is non‐surface redox active in the potential window where the metal oxide conversion occurs, and hence is more electrochemically stable during charge/discharge cycling. The paper presents the first time that Na has been used as a dopant in metal oxide anodes, and the result is excellent capacity retention and rate capability. More specifically, Na was added to Mn3O4 (in order to achieve a Mn:Na ratio of ~9:1), impregnated onto a carbon nanotube matrix. The concentration of Na considering the entire composition of the anode material was 0.5 atomic %. These electrodes were able to achieve a capacity ca. 750 mAh/g at a 1C rate and retain over 99% of that capacity over 500 cycles. They were also able to provide nearly twice the theoretical capacity of conventional graphite anodes under high rate discharge (609 mAh/g @ 5C), as well as achieve a higher capacity at 10C (~350mAh/g) than conventional graphite electrodes at 1C. 

The El Niño–Southern Oscillation (ENSO), which originates in the Pacific, is the strongest and most well-known mode of tropical climate variability. Its reach is global, and it can force climate variations of the tropical Atlantic and Indian Oceans by perturbing the global atmospheric circulation. Less appreciated is how the tropical Atlantic and Indian Oceans affect the Pacific. Especially noteworthy is the multidecadal Atlantic warming that began in the late 1990s, because recent research suggests that it has influenced Indo-Pacific climate, the character of the ENSO cycle, and the hiatus in global surface warming. Discovery of these pantropical interactions provides a pathway forward for improving predictions of climate variability in the current climate and for refining projections of future climate under different anthropogenic forcing scenarios.