Research On Multi-electrolyte Aluminum-air Battery

Aluminum air battery is a new type of high energy density chemical power supply,which has the advantages of abundant raw material storage,low price and long service life.The potential application value of aluminum-air batteries in new energy vehicles and other fields provides an important opportunity for its rapid development.Actively carrying out basic and applied research on aluminum-air batteries is of great significance to the development of China’s aluminum industry and automobile industry.The main contents are as follows:The research content of this paper is a multi-electrolyte system aluminum-air battery.When an alkaline electrolyte is used,the open circuit voltage（Voc）is about 1.5 V,and if a dual electrolyte system with an acid catholyte and an alkaline anolyte is used,a Voc of 2.2 V can be achieved.The dual electrolyte system can be realized with a microfluidic structure.（1）In this work,we present a recirculating dual-electrolyte aluminum/air microfluidic cell with porous hydrophilic polytetrafluoroethylene（PTFE）as the membrane.The short-circuit current density(J_sc)and V_oc is much higher compared with traditional single-electrolyte cell,and the electrolyte utilization is greatly enhanced with the membrane.With the PTFE membrane,the J_sc decreases from 648.93 to 497.01 m A cm^-2 by 23.41%only after 10 cycles of electrolyte circulation,while without the membrane,it drops from 713.80 to 29.42 m A cm^-2 by 95.88%.In addition,the PTFE membrane help stabilize V_oc to be around 2.15 V even after 10 cycles.（2）In this paper,a dual electrolyte aluminum/air microfluidic fuel cell with alkaline anolyte and acid catholyte was prepared.In the case of using alkaline anolyte and acid catholyte,the cell exhibits a high V_OC of～2.2 V with a J_SC of 1053 m A cm^-2.By delicately incorporating a regular porous carbon paper,an effective recirculation of electrolytes are achieved.The cell could exhibit an outstanding performance with an open-circuit voltage of2.2 V and a short-current density of 1 A cm-2.By delicately incorporating a regular porous carbon paper,an effective recirculation of electrolytes are achieved.（3）A novel tri-electrolyte aluminum/air cell（TEAAC）,consisting of an aluminum metal anode in an organic alkaline electrolyte,a cation exchange membrane,a bridge electrolyte,an anion exchange membrane,and an air cathode in an aqueous acidic catholyte,has been developed.With the introduction of organic alkaline anolyte,the hydrogen evolution associated with traditional aqueous solution was greatly suppressed,while maintaining the good electrochemical activity of aluminum under alkaline conditions.Using an acidic catholyte helps to boost up the battery voltage to 2.2 V and the carbonation issues with conventional air-cathode in alkaline solution were eliminated.