Hongyi Li

Since the launch of lithium-ion batteries, elements (such as silicon, tin, or aluminum) that can be alloyed with lithium have been expected as anode materials, owing to larger capacity. However, their successful application has not been accomplished because of drastic structural degradation caused by cyclic large volume change during battery reactions. To prolong lifetime of alloy anodes, we must circumvent the huge volume strain accompanied by insertion/extraction of lithium. Here we report tha

Abstract Sluggish solid‐phase diffusion has been an essential issue in developing intercalation electrode materials using multivalent ions. Compared to monovalent Li ions, the diffusion of multivalent ions is still not well understood. Here, combining first‐principles calculations with electrochemical experiments, it is shown that the diffusion of divalent Mg ions is significantly facilitated in Li–Mg dual‐ion systems, and the activation energy is remarkably reduced by the concerted interactions

Use of cooperative intercalation of Li and Mg ions in Mo₆S₈ to construct safe metal-anode batteries, in which the dangerous dendritic growth of Li is successfully suppressed by co-electrodeposition of Li and Mg.

Rechargeable magnesium batteries are promising candidates for post-lithium-ion batteries, owing to the large source abundance and high theoretical energy density. However, there remain few reports on constructing practical cells with oxide cathodes and Mg anodes at room temperature. In this work, we compare the reaction behavior of various MnO₂ polymorph cathodes in two representative electrolytes: Mg[TFSA]₂/G3 and Mg[Al(hfip)₄]₂/G3. In Mg[TFSA]<sub>2<

Using a roll-bonding process, the authors combine Al foils with different alloy additions into clad Al foils. The lithiation potential difference between the Al foils serves as a control factor to regulate lithium penetration during cycles.

Uniformly distributed Si in the Al matrix as a solid solution induces a pinning effect, prevents cracking of the Al grains, suppresses pulverization and improves the cycling stability of Al-foil anodes in rechargeable lithium batteries.

In rechargeable magnesium batteries, Mg2+ usually exhibits sluggish kinetics and large overpotentials during intercalation into cathode materials due to the strong Coulomb interaction with the host structures. In this work, we show that introducing alkali ions (Li+, Na+, or K+) to construct dual-cation electrolytes significantly reduces the discharge overpotential and increase the discharge capacity of a hollandite-type α-MnO2 cathode. Two necessary conditions are found to activate the concerted

Alkali metals are expected to be used for rechargeable metal anode batteries owing to their low electrode potentials and large capacities. However, they face the well-known fatal problem of “dendritic growth” while charging. Here, we present a detailed investigation on electrolytes where alkaline earth salts are introduced to inhibit dendrite growth in alkali metal electrodeposition. Specifically, focusing on CaTFSA2 as an exemplary additive, we reveal that dendrite-free morphology upon alkali m

This work introduces the use of multivalent cations ( e.g. Ca 2+ , Ba 2+ , La 3+ and Ce 3+ ) as electrolyte additives in lithium-metal anode batteries with a focus on solvation structure modification, SEI formation and lithium growth.

Alkali metals, such as lithium and sodium, have been expected to be used for rechargeable metal-anode batteries owing to their low electrode potentials and large capacities. However, the well-known fatal problem, “dendritic growth” causing a dangerous short circuit, is faced while charging the batteries. Here, through a comprehensive study with electrochemical experiments, Raman and soft X-ray emission spectroscopies, density-functional-theory calculation, and molecular dynamic simulations, we p

Magnesium batteries are expected to be promising post lithium-ion batteries owing to several intriguing advantages, such as a relatively safe metal anode, low production cost, and high energy density. There are, however, still essential issues that hinder the development of practical magnesium batteries. In this chapter, we show that employing Mg ions with Li ions to construct Mg–Li dual-ion batteries is an effective approach to realize high performance rechargeable batteries with safe metal ano

Alloy anode materials, such as silicon, tin, and aluminum, are expected to be used in rechargeable lithium batteries owing to high theoretical capacities, compared to conventional carbonaceous anodes. However, the high capacities inevitably cause drastic volume change (+100~300%) of the anode materials during battery reactions (i.e., lithium insertion and extraction), which usually leads to fatal structural degradation.[1,2] Although downsizing the anode materials into fine particles is an effec

There is a growing demand for high energy-density rechargeable batteries to construct high performance electric vehicles and renewable energy storage systems. As a candidate of post Li-ion batteries (LIBs), Mg rechargeable batteries (MRBs) have a great potential to attain considerable energy density higher than current commercial LIBs. This is mainly because Mg shows a non-dendritic growth behavior during charging. This feature allows Mg metal to be used as an anode material, which is in a sharp