Aqueous batteries are promising for future large-scale energy storage because of their environmental friendliness, low costs, and storage of protons. For practical application, a neutral or weak acidic electrolyte is preferred, which however always leads to insoluble alkaline salts as by-products caused by the proton storage. Little is known regarding the by-products that are often regarded as harmful to the battery. Here, we demonstrate that the by-products are crucial for reversible charge storage. The by-products can create a localized alkaline environment, which is essential to further drive the following deprotonation. The addition of artificial by-products could even change the storage mechanism of conducting polymer (polyaniline) and its oligomers from the poor storage of large anions to reversible proton storage. Remarkably, the change in storage mechanism enhances the ionic diffusion coefficients by about two orders of magnitude and boosts the capacity by 20 times, with excellent rate capability and cyclability.

中文翻译：

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副产品在质子储存中的作用


水系电池因其环境友好、成本低和质子储存等优点，有望在未来的大规模储能中发挥作用。对于实际应用，中性或弱酸性电解质是首选，但这总是会导致质子储存引起的不溶性碱性盐作为副产物。对于通常被认为对电池有害的副产品，我们知之甚少。在这里，我们证明了副产品对于可逆电荷存储至关重要。副产物可以产生局部碱性环境，这对于进一步驱动后续的去质子化至关重要。人工副产物的添加甚至可以改变导电聚合物（聚苯胺）及其低聚物的储存机制，从大阴离子的不良储存转变为可逆的质子储存。值得注意的是，存储机制的改变使离子扩散系数提高了约两个数量级，容量提高了 20 倍，具有出色的倍率能力和可循环性。