双氟磺酰亚胺锂作为一种新型电解质锂盐,其纯度对锂离子电池的性能有着非常大的影响。为制备高纯度双氟磺酰亚胺锂产品,基于响应曲面法系统研究了料液比（粗品占提纯溶剂的质量分数）、结晶时间和降温速率3个工艺参数及其交互作用对提纯后产品纯度的影响,并建立了相关的数学预测模型。结果表明：在料液比为20.7%、结晶时间为30.2 h、降温速率为3.4 ℃/h条件下,制备的双氟磺酰亚胺锂产品纯度为99.98%。

As a new lithium electrolyte salt,the purity of lithium difluorosulfimide（LiFSI） has great influence on the perfor-mance of lithium ion battery.In order to prepare high-purity LiFSI product,three technological parameters including ratio of material to liquid（mass ratio of crude product to purified solvent）,crystallization time and cooling rate and their interaction effects on the purity of the purified products were systematically studied based on the response surface method,and the rele-vant mathematical prediction model was established.Results showed that under the conditions that the ratio of material to liq-uid was 20.7%,the crystallization time was 30.2 h and the cooling rate was 3.4 ℃/h,the purity of the prepared LiFSI product was 99.98%.