Despite high power density, fast charging/discharging rate, and long operational lifetime, large-scale application of supercapacitor (SC) is limited by its intrinsically low energy densities (of 5–8 Wh kg⁻¹ (gravimetric) and 5–8 Wh L⁻¹ (volumetric)), which are at least 10-fold lower than battery. Since the invention of graphene in 2004, graphene-based SCs have set the upper performance limit of the symmetric carbon-based SCs due to superior electrical conductivity and very high accessible surface area of graphene. Still, only two companies have commercialised graphene-based supercapacitors thus far. Their maximum achievable energy density (i.e., 11.65 Wh kg⁻¹) is too low to make them competitive against batteries in high-energy applications. To this end, this comprehensive review focuses on the material- and device-level approaches to high energy density graphene-based conventional macroscale SCs (≥11.65 Wh kg⁻¹) and flexible SCs and microsupercapacitors (≈0.3–10 mWh cm⁻³; ≈300–16000 μWh cm⁻²). It includes a description on how each approach is implemented and an explanation of how each can provide effective research results. This review also meticulously discusses the underlying challenges and possible solutions to achieve high energy density graphene-based SCs in practice.

尽管功率密度高，充电/放电速率快且使用寿命长，但超级电容器（SC）的大规模应用受到其固有的低能量密度（5-8 Wh kg ^-1（重力）和5-8 Wh）的限制。 L ^-1（体积）），至少比电池低10倍。自2004年发明石墨烯以来，由于石墨烯的优异导电性和非常高的可利用表面积，石墨烯基SC设定了对称碳基SC的性能上限。到目前为止，只有两家公司将石墨烯基超级电容器商业化。其最大可达到的能量密度（即11.65 Wh kg ^-1）太低，无法使其在高能应用中与电池竞争。为此，本篇综述着重于材料和器件级方法，以解决基于高能量密度石墨烯的常规大型SC（≥11.65Wh kg ^-1），柔性SC和微型超级电容器（≈0.3–10 mWh cm ^{-3）的问题}。 ≈300-16000μWhcm ^-2）。它包括对每种方法的实施方式的说明，以及每种方法如何提供有效研究结果的说明。这篇综述还认真地讨论了在实践中实现基于高能量密度的基于石墨烯的SC的潜在挑战和可能的解决方案。