Amorphous nanomaterials have been regarded as extremely promising electrode materials for battery-like energy storage device (BESD) due to their atomic disorder, homogeneous and metastable properties, etc. Here, an amorphous NiCo layered double hydroxide (NiCo LDH) with different morphologies is synthesized for the first time by a green, economical and practicable ultrahigh voltage electrophoretic deposition method (EPD), constructing a 3D architecture with high specific surface area as the positive electrode for energy storage. The obtained amorphous NiCo LDH nanosheets/CFP electrode exhibits a high specific capacitance of 347mFcm−3 and a good retention of 88.3% after 10000 cycles. Moreover, an asymmetric BESD based on the amorphous NiCo LDH/CFP and commercial activated carbon (AC) offers an energy density of 41.67Whcm−3 at the power density of 0.5kWcm−3 and excellent cycle life (only 0.3% deterioration of its initial specific capacitance after 10000 cycles). The good performance of amorphous NiCo LDH nanosheets in capacitance is ascribed to the high inner charge storage and efficient ion transportation. This research provides a new method to control the morphologies of amorphous nanomaterials by EPD technique in the future.