Porous carbons derived from microalgae were prepared using a pyrolysis method. The microstructure and electrochemical performance were studied using X-ray diffraction, Raman spectrometer, scanning and electron microscopy techniques. The electrochemical performance was investigated using electrochemical methods. A carbon sample pyrolyzed at 900 degrees C exhibited a hierarchical pore structure with a large amount of microcrystalline graphitic domains. As a result, this sample delivered the best electrochemical performance with specific charge capacities of 445 mAh g(-1) at 0.1 C and 370 mA h g(-1) at 1 C, respectively. In addition, this sample showed a capacity retention of 95% after 500 cycles at 1 C. The good electrochemical performance of the pyrolytic carbon is attributed to the combined contributions of the hierarchical porous structure and microcrystalline graphitic carbon domains. (C) 2016 Elsevier Ltd. All rights reserved.