This　study　thoroughly　investigated　the　effects　of　activation　conditions　on　pore　structure　development　using　response　surface　methodology　with　a　central　composite　design.　The　activated　carbon　sphere　(ACS)　derived　from　phenolic　formaldehyde　resins　by　carbonization　and　fluidized　activation　was　examined　and　characterized.　The　pore　size　distribution　of　ACS　samples　was　all　in　the　microporous　and　mesoporous　scales.　ACS　with　an　ultra-high　specific　surface　area　of　3142　m2　g−1　and　total　pore　volume　of　1.513　cm3　g−1　was　successfully　obtained　at　900　°C　for　4　h.　Electric　double-layer　capacitor　(EDLC)　electrodes　derived　from　ACS　with　different　activation　conditions　were　examined　by　using　cyclic　voltammetry　and　galvanostatic　charge/discharge　to　comprehend　the　influence　of　surface　area,　pore　volumes,　and　the　amount　of　binder　on　the　electrochemical　performance.　The　optimal　EDLC　electrode　was　obtained　using　ACS　with　the　largest　specific　surface　area　and　pore　volume　with　5　wt%　of　binder　addition.　The　specific　capacitance　was　143.7　F　g−1　in　a　1　M　H2SO4　solution.　The　cyclical　stability　of　the　carbon　electrode　was　also　examined　under　5000　cycles,　and　the　charge/discharge　efficiency　remained　nearly　100　%　without　deterioration.　This　study　provides　insights　into　fabricating　ultra-high　surface　area　ACS　and　their　potential　application　as　supercapacitors.　©　2024　Elsevier　B.V.