Study On Electrolytic Capacitor Anode Of Titanium Monoxide

Electrolytic capacitors are used expensively with a large market.Due to the influence of properties, resource and cost, anode material ofelectrolytic capacitor changed from Al to Ta, Nb and TiO in turn. Thus,study on the anode material of electrolytic capacitor is very important.Titanium is resourceful and cheaper as compared with other materials.But it is difficult to form the oxide layer on the Titanium anode. Theelectrolytic capacitor anode of TiO concerned in this paper have theadvantage of high capacity, little leakage current, resourceful and lowcost.The preparation of TiO powder by solid-solid reaction between Ti(TiH₂) and TiO₂ is studied. The manufacture of TiO anode is studied indetail by orthogonal experiments and analysis of variance and thetechnological conditions are further optimized according to thetechnological process of sinter electrolytic capacitors: powder pressing,sinter and oxidation of the titanium anode. The specific capacity of TiOanode prepared is 45312μF·V·g^-1,the loss is 0.316, the leakage current(value of K) is0.00204μA·μF^-1·V^-1, and the electrical properties hasachieved the standard (SJ/T10030-91) for non-solid polymer Tantalumcapacitors.The Kinetic analysis to the preparation of TiO powder shows thatthe reaction between Ti (or TiH₂) and TiO₂ is controlled by thediffusion of oxide in different phases, so roasting in high temperaturecan facilitate the reaction.The mechanism of sintering and the sintering condition's effort tothe electrical properties is analysed by SEM. It shows that the small orirregular power can facilitate the anode sintering .Whileover-temperature agglomeration can reduce the void fraction of theanode even cause closed pore and increase the loss and cut downcapacity.The fabric of oxide film is analysed by EDX, the fabric andelectrical of oxide film is influenced by P enter to oxide film, during anode forming in phosphoric acid; but no impurity element enter intooxide film during anode forming in ammonium pentaborate acid.As a new type of materials for electrolytic capacitor, the study ofTiO is not enough. Although the electrical properties of TiO prepared inthis paper as anode has achieved the standard (SJ/T10030-91) fornon-solid polymer Tantalum capacitors, there is still a long distancefrom application, which needs follow-up research like anode forming,envelope and package. As an excellent electrical properties, low cost,high reliability electrolytic capacitors, the electrical capacitors of TiOhas prospective future, it will replace Al,Ta electrolytic capacitors incertain fields. As a new-style electrolytic capacitor, it is estimated thatTiO capacitor will have a bright market in the future and bring aboutenormous economic benefits.