NOVELTY - A composite particle (P1) comprises first particle component having body and surface portions, where both portions define together structured particle, both portions contain active material, and the surface portion has at least one structural feature and at least one void; and second particle component having removable filler, where the filler is contained within at least one void comprised within the surface portion of the first component, and the filler either has sublimation or disintegration temperature of at least 50 degrees C and/or is soluble in ionic liquid or electrolyte solution. INDEPENDENT CLAIMS are included for the following: (1) forming (M1) composite particle involving mixing first particle component with filler in liquid form; (2) composite material (C1) comprising the composite particle (P1) and a binder; (3) making composite material involving forming a slurry in a suitable solvent of the composite particle (P1) or the composite material (C1) and coating the slurry onto a substrate and removing the solvent; (4) electrode (E1) comprising the composite particle (P1) or the composite material (C1) and a current collector; (5) making an electrode involving forming a slurry in a suitable solvent of the composite particle (P1) or the composite material (C1), coating the slurry onto a current collector and removing the solvent; (6) electrochemical cell (C2) comprising the electrode (E1) and a cathode; (7) device comprising the electrochemical cell (C2); (8) composition (C3) comprising a stable suspension of the composite particle (P1) or the composite material (C1) in a liquid carrier; (9) storing (M2) the composite particle (P1) or the composite material (C1) involving forming a stable suspension of the composite particles or composite material in a liquid carrier.    USE - As composite particle; as composite material; and in the manufacture of at least one device selected from electrochemical cell, metal ion battery, fuel cell, thermal battery, photovoltaic device, solar cell, filter, sensor, electrical capacitor, thermal capacitor, gas/vapor sensor, thermal or dielectric insulating device, device for controlling or modifying the transmission, absorption or reflectance of light or other forms of electromagnetic radiation, chromatography or wound dressings (claimed).    ADVANTAGE - The composite particles make it easier to disperse the active materials evenly throughout a composite material by the reduction or elimination of agglomeration; and are useful in secondary battery applications.