Thick electrode was promising to increase the energy density in device (battery or supercapacitor) scale, but always suffered the ion polarization upon high rate discharge. We reported the use of 3D Al foam (current collector) to host graphene (with high surface area but very low packing density) to fabricate 450 ​μm thick electrode with mass loading of 10–15 ​mg ​cm⁻². The space confinement effect of Al wires on graphene at any regions offered sufficient ordered diffusion channel of liquids, alleviating the ion polarization significantly, compared to the same thick graphene sheet pasted on 2D Al foil by simulation with COMSOL software. The 100 ​F pouch supercapacitor with ionic liquids at 4 ​V exhibited low contact resistance, high specific capacitance in a wide range of current densities, and simultaneously the volumetric energy density of 18 ​Wh L⁻¹ and the power density of 5 ​kW ​kg⁻¹, far better than those of current commercial device.

厚电极有望增加器件（电池或超级电容器）规模的能量密度，但在高速率放电时始终会遭受离子极化。我们报道了使用3D Al泡沫（集电器）来承载石墨烯（具有高表面积但堆积密度非常低）以制造450μm厚，质量负载为10-15 mg cm ^-2的电极。与通过COMSOL软件模拟粘贴在2D Al箔上的相同厚石墨烯片相比，Al丝在任何区域对石墨烯的空间限制作用提供了足够的液体有序扩散通道，从而显着减轻了离子极化。具有4V离子液体的100 F袋式超级电容器在各种电流密度下均表现出低接触电阻，高比电容，同时体积能量密度为18 Wh L ^-1和功率密度为5 kW kg ^-1，远优于目前的商用设备。