Experimental Study On The Influence Of Electrode Temperature And Electrolyte Formula On The Performance Of Thermo-electrochemical Cells

As a technical means of waste heat recovery,thermoelectric power generation is attractive for its characteristics of no pollution,compact structure,no moving parts,no noise and no maintenance.Thermoelectric power generation is more mature in the development of solid materials and semiconductor materials.In recent years,a new technical proposal named thermo-electrochemical cell appears which has higher Seebeck coefficient,lower cost,and is able to adapt to the complex heat source surface,so it has a certain prospect and become one of the hot research directions.In this paper,platinum electrode and potassium ferricyanide/potassium ferrocyanide mixed aqueous solution are used as electrolyte to build salt bridge thermoelectric chemical cell.The effect of electrode temperature and electrolyte formula on its power generation performance is studied.After the establishment of the physical model of the battery,the semiconductor temperature controller is selected as the temperature control device according to the accuracy and timeliness requirements of the temperature control,and the component selection and construction of the performance test bench are carried out according to the test accuracy,size layout and other aspects,which is used for the accurate measurement of the relevant power generation performance parameters of the thermochemical battery under various working conditions.Secondly,the orthogonal test design is carried out which is high-efficiency and economic.The built performance test bench is used,and the test is carried out after the selection of indicators,factors,levels,orthogonal tables,etc.After data processing and error analysis,the range analysis and variance analysis are carried out respectively,so as to preliminarily obtain the priority level of temperature and concentration on the open circuit voltage and maximum output power of thermochemical battery The results show that there is no significant interaction between factors.Finally,after confirming that there is no obvious interaction between the factors,the electrode temperature and the electrolyte formula are studied.Among them,in the study of electrode temperature,it is divided into electrode temperature difference and electrode average temperature.The thermoelectric chemical cell composed of0.4mol/kg potassium ferricyanide/potassium ferrocyanide electrolyte and platinum plate electrode can obtain the best electric energy when the electrode temperature is50℃and 70℃,respectively.At this time,the value of the specific power is 0.827μW/（m²·K²）.In the study of the electrolyte formula,it is divided into two cases:1:1ratio and other ratio.Under the experimental conditions,when the concentration of potassium ferricyanide is 0.001mol/kg and the concentration of potassium ferrocyanide is 0.2mol/kg,the maximum open circuit voltage is 48.6mV;when the concentration of potassium ferrocyanide is 0.35mol/kg and the concentration of potassium ferrocyanide is 0.4mol/kg,the maximum output power of the battery is2.19×10^-7W.