The Influence of Step-By-Step Air Exposition of the Zr-Mn-Cr-Ni-V Alloy on Cycle Life
In the course of the research it was determined that step-by-step air exposition of the Zr-Mn-Cr-Ni-V alloy (in the form of ingot and powder) facilitating the formation of concentration inhomogeneity significantly increases the cycle life of electrodes. An electrode compacted of step-by-step exposited ingot of the alloy demonstrates no loss of capacity during 190 cycles. With the decrease of porosity, caused by adding the nickel powder with significantly smaller particle size than that of particles of the alloy, or by increase of plasticizer content from 5 % to 10 %, the electrodes are being destroyed much sooner due to formation of more dense packing.
Based on the polarization curves of the researched alloy and manganese that demonstrate similar electrochemical behavior in non-oxidized state and stability in oxidized state, the conclusion is made that the increased stability and, as a consequence, the cycle life of the air-exposited alloy is mainly achieved due to manganese which is stably passive in oxidized state.
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