锌金属作为锌离子电池应用最广泛的负极材料之一，其具有较高的理论容量，广泛的地壳分布，较低的电化学势，较高的化学稳定性，较低的成本等优势，受到了研究者的广泛关注。但由于锌负极和电解液界面的不稳定性，在近中性或微酸性溶液中，会有自发的腐蚀行为、析氢行为和枝晶生长行为。需要对电解液进行改性以调控锌负极与电解液界面的稳定性。电解液添加剂策略具有工艺简洁，用量较少，有效性好，成本易控制等优势，是锌离子电池电解液工程中最为常用的改性策略之一。本文基于锌离子电池的电解液添加剂策略制备了含两种不同添加剂的电解液，并研究电解液添加剂作用下锌负极的电化学性能。通过制备含有硫酸铟添加剂的硫酸锌电解液，组装了锌锌对称电池，在电池静置过程中，铟离子与锌金属发生了置换反应，形成了铟金属保护层，减少了锌箔表面和电解液的直接接触，减缓了锌金属负极的腐蚀和析氢反应。在电池的循环过程中，铟金属保护层提供了大量形核位点，使锌的形核过电位和电荷传输电阻降低，指引了锌的均匀沉积。以纯锌箔作为极片组装对称电池，通过硫酸铟添加剂的作用，在1 mA cm-2的电流密度和0.5 mAh cm-2的每周截止容量下仍能循环超过2000 h，并且平均极化电压不超过50 mV。在电解液添加剂作用下的活性炭锌离子混合电容器和VO2全电池表现出优异的倍率性能和循环稳定性。通过制备含有氟化铵添加剂的硫酸锌电解液，与纯锌箔组装对称电池，溶液中的铵根离子可以优先地吸附在锌金属负极的表面，形成动态的静电屏蔽层，抑制枝晶的形成，而溶液中的氟离子可以调节溶液中的氢键网络，降低自由水的活性，从而抑制副反应的发生。以纯锌箔作为极片组装对称电池，在氟化铵添加剂的作用下，即使在10 mA cm-2的电流密度，1 mAh cm-2的每周截止容量下仍能循环超过3000周，且极化电压相比于改性前减小。在电解液添加剂作用下的α-MnO2全电池表现出优异的倍率性能和循环稳定性。
As one of the most widely used anode materials for zinc ion batteries, zinc metal has received a lot of attention from researchers for its advantages such as high theoretical capacity, wide crustal distribution, low electrochemical potential, high chemical stability and low cost. However, due to the instability at the interface between the zinc cathode and the electrolyte, spontaneous corrosion behaviour, hydrogen precipitation and dendrite growth can occur in near-neutral or slightly acidic solutions. Modifications to the electrolyte are required to regulate the stability of the zinc anode and electrolyte interface. The electrolyte additive strategy is one of the most commonly used modification strategies in zinc ion battery electrolyte engineering because of its simplicity, low dosage, good effectiveness and easy cost control. In this paper, electrolytes containing two different additives are prepared based on the electrolyte additive strategy for zinc ion batteries and the electrochemical properties of the zinc cathode under the action of the electrolyte additives are investigated.A zinc-zinc symmetric cell was assembled by preparing a zinc sulphate electrolyte containing indium sulphate additives. During the resting process of the cell, indium ions underwent replacement reactions with zinc metal, forming an indium metal protective layer, which reduced the direct contact between the zinc foil surface and the electrolyte, slowing down the corrosion and hydrogen precipitation reaction of the zinc metal anode. During the cell cycle, the indium metal layer provides a large number of nucleation sites, which reduces the nucleation overpotential, charge transfer resistance of zinc and guides the uniform deposition of zinc. Symmetrical cells assembled with pure zinc foil as an electrode can still cycle for more than 2000 h at a current density of 1 mA cm-2 and a cut-off capacity of 0.5 mAh cm-2 with a polarisation voltage of no more than 50 mV in the presence of indium sulphate additives. activated carbon zinc ion capacitors and VO2 full cells in the presence of electrolyte additives exhibit excellent multiplicative performance and cycling stability.By preparing a zinc sulphate electrolyte containing ammonium fluoride additives and assembling a symmetric cell with pure zinc foil, the ammonium ions in the solution can preferentially adsorb to the surface of the zinc metal anode and inhibit the formation of dendrites, while the fluorine ions in the solution can modulate the hydrogen bonding network in the solution and reduce the activity of free water, thus inhibiting the occurrence of side reactions. The assembly of symmetrical cells using pure zinc foil as the electrode was able to cycle for more than 3000 cycles in the presence of ammonium fluoride additives, even at a current density of 10 mA cm-2 and a cut-off capacity of 1 mAh cm-2, and the polarisation voltage was reduced compared to that before the modification. The α-MnO2 full cell in the presence of electrolyte additives exhibited excellent multiplicative performance and cycling stability.
