Aqueous zinc metal batteries are receiving broad attention owing to their promising characteristics of low cost, high safety, and environmental benignity. However, severe side reactions over zinc metal anodes (i.e., dendrite growth and by‐product formation) dramatically limit their further development. Herein, the key problems are tackled by introducing a dual‐function electrolyte additive (ammonium cation‐based salts) to achieve long‐term and highly reversible zinc plating/stripping. Specifically, the cation can homogenize the zinc deposition via the charge shielding effect and inhibit by‐product formation by participating in the constitution of contact ion pairs. In such a way, the Zn||Zn symmetric cell stably cycles over 2145 h at a current density of 1 mA cm−2 with the overpotential of merely 25 mV. In addition, the reversibility of energy storage devices based on manganese dioxide and an activated carbon cathode is effectively enhanced. This strategy provides a promising approach for the future development of advanced aqueous metal batteries.

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Polymer-based piezoelectric devices are promising for developing future wearable force sensors, nanogenerators, and implantable electronics, etc. The electric signals generated by them are often assumed as solely coming from the piezoelectric effect. However, triboelectric signals originated from contact electrification between the piezoelectric devices and the contacted objects can produce non-negligible interfacial electron transfer, which is often combined with the piezoelectric signal to give a triboelectric-piezoelectric hybrid output, leading to an exaggerated measured “piezoelectric” signal. Herein, a simple and effective method is proposed for quantitatively identifying and extracting the piezoelectric charge from the hybrid signal. The triboelectric and piezoelectric parts in the hybrid signal generated by a poly(vinylidene fluoride)-based device are clearly differentiated, and their force and charge characteristics in the time domain are identified. This work presents an effective method to elucidate the true piezoelectric performance in practical measurement, which is crucial for evaluating piezoelectric materials fairly and correctly.