A Review on the Conventional Capacitors, Supercapacitors, and Emerging Hybrid Ion Capacitors: Past, Present, and Future

Abstract

Electrochemical energy storage (EES) devices with high‐power density such as capacitors, supercapacitors, and hybrid ion capacitors arouse intensive research passion. Recently, there are many review articles reporting the materials and structural design of the electrode and electrolyte for supercapacitors and hybrid capacitors (HCs), though these reviews always focus on individual supercapacitors or single HCs. Herein, the conventional capacitor, supercapacitor, and hybrid ion capacitor are incorporated, as the detailed description of conventional capacitors is very fundamental and necessary for the better understanding and development of supercapacitors and hybrid ion capacitors, which are often ignored. Therefore, herein, the fundamentals and recent advances of conventional capacitors, supercapacitors, and emerging hybrid ion capacitors are comprehensively and systematically summarized in terms of history, mechanisms, electrode materials, existing challenges, and perspectives. At the same time, it is believed that a comprehensive and fundamental understanding for capacitor‐related EES devices is provided in the review and has a great guiding role for future development.

d -Calcium pantothenate-derived porous carbon: carbonization mechanism and application in aqueous Zn-ion hybrid capacitors

“…6b shows the CV curves of DPCs-800 at different scan rates. 36,37 Broad redox shoulders at around 0.7, 1.2, and 1.6 V can be observed during the charge and discharge process, representing a pseudocapacitive behaviour of the ZIHCs. At different scan rates, the shape of the CV curves remains basically the same, indicating the excellent stability and fast ions transport kinetics of DPCs-800.…”

d -Calcium pantothenate-derived porous carbon: carbonization mechanism and application in aqueous Zn-ion hybrid capacitors

“…6b shows the CV curves of DPCs-800 at different scan rates. 36,37 Broad redox shoulders at around 0.7, 1.2, and 1.6 V can be observed during the charge and discharge process, representing a pseudocapacitive behaviour of the ZIHCs. At different scan rates, the shape of the CV curves remains basically the same, indicating the excellent stability and fast ions transport kinetics of DPCs-800.…”

Capacitive Structure‐Based Acoustic Triboelectric Nanogenerator for Advanced Warning Sound Recognition

“…The capacitor mechanism of the CS-TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [26] This can be explained using Equation (2), which describes the charge characteristics as follows:…”

“…The capacitor mechanism of the CS‐TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [ 26 ] This can be explained using Equation (), which describes the charge characteristics as follows:where C is the capacitance of the capacitor, Q is the charge, V is the voltage across the capacitor, ε 0 is an electric constant (vacuum permittivity), ε r is a dielectric constant (relative permittivity), A is the area of the dielectric, and d is the thickness of the dielectric. As the distance between the two electrodes in the capacitor increases, the capacitance and output decrease.…”

Scaleup Sodium‐Ion Capacitor Ah‐Level Pouch Cells Enable 100 C Ultrafast Charging Capabilities

“…However, when the operating voltage increases to 3.4 V for cell #2 ( m + : m – = 2.7), the AC NE operates until 0.15 V vs. Na + /Na, accompanied by large capacity losses with a low ICE of 19.2% (Figure 3b), which is consistent with the half‐cell results (Figure 2a) and traditional concepts. [ 37 ] Remarkably, when m + : m – is controlled at 1.3, the 3‐electrode cell #3 shows highly reversible GCD profiles in the wide voltage window of 0–3.4 V in DME electrolyte, in which the AC NE efficiently operates the EDL capacitive reaction at potentials as low as 0.05 V vs. Na + /Na (Figure 3c).…”

d -Calcium pantothenate-derived porous carbon: carbonization mechanism and application in aqueous Zn-ion hybrid capacitors

“…6b shows the CV curves of DPCs-800 at different scan rates. 36,37 Broad redox shoulders at around 0.7, 1.2, and 1.6 V can be observed during the charge and discharge process, representing a pseudocapacitive behaviour of the ZIHCs. At different scan rates, the shape of the CV curves remains basically the same, indicating the excellent stability and fast ions transport kinetics of DPCs-800.…”

Capacitive Structure‐Based Acoustic Triboelectric Nanogenerator for Advanced Warning Sound Recognition

“…The capacitor mechanism of the CS-TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [26] This can be explained using Equation (2), which describes the charge characteristics as follows:…”

“…The capacitor mechanism of the CS‐TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [ 26 ] This can be explained using Equation (), which describes the charge characteristics as follows:where C is the capacitance of the capacitor, Q is the charge, V is the voltage across the capacitor, ε 0 is an electric constant (vacuum permittivity), ε r is a dielectric constant (relative permittivity), A is the area of the dielectric, and d is the thickness of the dielectric. As the distance between the two electrodes in the capacitor increases, the capacitance and output decrease.…”

Scaleup Sodium‐Ion Capacitor Ah‐Level Pouch Cells Enable 100 C Ultrafast Charging Capabilities

“…However, when the operating voltage increases to 3.4 V for cell #2 ( m + : m – = 2.7), the AC NE operates until 0.15 V vs. Na + /Na, accompanied by large capacity losses with a low ICE of 19.2% (Figure 3b), which is consistent with the half‐cell results (Figure 2a) and traditional concepts. [ 37 ] Remarkably, when m + : m – is controlled at 1.3, the 3‐electrode cell #3 shows highly reversible GCD profiles in the wide voltage window of 0–3.4 V in DME electrolyte, in which the AC NE efficiently operates the EDL capacitive reaction at potentials as low as 0.05 V vs. Na + /Na (Figure 3c).…”

d -Calcium pantothenate-derived porous carbon: carbonization mechanism and application in aqueous Zn-ion hybrid capacitors

“…6b shows the CV curves of DPCs-800 at different scan rates. 36,37 Broad redox shoulders at around 0.7, 1.2, and 1.6 V can be observed during the charge and discharge process, representing a pseudocapacitive behaviour of the ZIHCs. At different scan rates, the shape of the CV curves remains basically the same, indicating the excellent stability and fast ions transport kinetics of DPCs-800.…”

Capacitive Structure‐Based Acoustic Triboelectric Nanogenerator for Advanced Warning Sound Recognition

“…The capacitor mechanism of the CS-TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [26] This can be explained using Equation (2), which describes the charge characteristics as follows:…”

“…The capacitor mechanism of the CS‐TENG for accumulating charge is inversely proportional to the thickness of the dielectric, making it more difficult to generate charges, resulting in a lower output. [ 26 ] This can be explained using Equation (), which describes the charge characteristics as follows:where C is the capacitance of the capacitor, Q is the charge, V is the voltage across the capacitor, ε 0 is an electric constant (vacuum permittivity), ε r is a dielectric constant (relative permittivity), A is the area of the dielectric, and d is the thickness of the dielectric. As the distance between the two electrodes in the capacitor increases, the capacitance and output decrease.…”

Scaleup Sodium‐Ion Capacitor Ah‐Level Pouch Cells Enable 100 C Ultrafast Charging Capabilities

“…However, when the operating voltage increases to 3.4 V for cell #2 ( m + : m – = 2.7), the AC NE operates until 0.15 V vs. Na + /Na, accompanied by large capacity losses with a low ICE of 19.2% (Figure 3b), which is consistent with the half‐cell results (Figure 2a) and traditional concepts. [ 37 ] Remarkably, when m + : m – is controlled at 1.3, the 3‐electrode cell #3 shows highly reversible GCD profiles in the wide voltage window of 0–3.4 V in DME electrolyte, in which the AC NE efficiently operates the EDL capacitive reaction at potentials as low as 0.05 V vs. Na + /Na (Figure 3c).…”