In order to find superior MgO powders for immobilizing electrolyte in lithium-thermal battery,the surface morphology and melting point of five commercial MgO powders and EB materials were characterized by scanning electron microscopy (SEM) and DSC,respectively.The immobilizing effect of MgO powder was evaluated by electrolyte leakage behavior of separator pellets.The experimental results indicate that when the content of EB material increases from 30％ to 60％,the electrolyte leakage content decreases from 109 to 27 mg/cm2,the 3# MgO powder with small particle size,better dispersive particles and large pore size is the most excellent binder for molten salts.The other MgO materials exhibit disordered surface morphologies,and the powder is poor dispersive particles with small pore size and poor immobilizing effect for electrolyte.The EB materials were used as separator in thermal batteries.The discharge tests of single cell were performed at constant current density of 0.2 A/cm2,and pulse current was delivered on the load to gain the polarization resistance of batteries.The discharge tests show that thermal battery with 3# MgO powder as binder has the highest capacity and lowest polarization resistance.%为获得优良的电解质粘合剂材料,采用扫描电镜(SEM)、差热分析(DSC)等测试手段对5种MgO粘合剂材料和对应组成的EB电解质材料进行了微观形貌和熔点变化的观察分析;通过测试电解质泄漏量,评价不同MgO和不同配比EB的流动抑制效果.结果表明:3#样品粒径细小较为均匀,颗粒分散好、孔隙较大,在EB中的含量从30％增加到60％,电解质泄漏量从109 mg/cm2减小到27 mg/cm2,对电解质流动抑制作用较强;其他样品的形貌无规则化较重,存在团聚现象,颗粒之间子孔隙较小,流动抑制效果较差.将不同EB材料分别作为隔离层制成单体电池,以0.2 A/cm2的电流密度进行恒流负载放电,同时施加脉冲电流进行电池内阻的测量,3#样品制成的热电池放电容量最强、内阻最小.
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