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Natural pyrite (FeS2) as a cathode the active substance Li/FeS2 battery is a lithium primary battery hot research field . Li/FeS2 batteries as a new type of lithium battery has the following advantages : high specific energy and operating voltage , and low self-discharge rate , leak-proof performance , wide operating temperature range , environmental pollution and other characteristics . In this thesis, pyrite (FeS2) cathode material heat treatment , and study of the physical and chemical properties before and after heat treatment pyrite (FeS2) , electrochemical properties . Subjected to a heat treatment in the temperature range of 100 ° C to 550 ° C for pyrite , and heat treatment of the samples were tested : by thermal gravimetric - the stability of the differential thermal analysis of the test sample , the bulk density , the liquid absorption amount , the FeS2 content in the sample , the crystal structure , particle morphology (SEM) and the discharge capacity. The results show that : pyrite (FeS2) after heat treatment at 400 ℃ , respectively 3mA · cm -2 , 0.5mA · cm -2 , a current density of 0.2 mA cm -2 discharge , discharge capacity , respectively 450.7mAh · g- 1,500.5 mAh · g-1, 670.9mAh · g-1. Optimized Li/FeS2 ratio of the positive electrode material in the battery , including the amount of the conductive agent, a binder and an electrolyte , the analysis of the influence of these factors on the Li/FeS2 discharge of the battery performance and safety performance . By orthogonal experiment to get a better cathode ratio : graphite : PVDF: electrolyte = 9.0:7.5:1.8 . And to discharge performance testing under different discharge conditions (2.2Ω, 10Ω, 50 mA, 1000 mA) . The results show that : the negative electrode with Li , FeS2 the positive electrode , made into a Li/FeS2 a primary battery , 1000mA constant current discharge to 1.1V , discharge time is 6.5 to 7 times the alkaline Zn/MnO2 battery . 10Ω constant resistance discharge to 1.1V, and a Li/FeS2 cell discharge performance alkaline Zn/MnO2 battery 2 to 2.5 times . Different electrode preparation process on the electrode performance . Two preparation process : film method and the coating method. Using compression molding process , the surface of the electrode sheet uneven and rough and, therefore , the moldability of the electrode . The electrodes of the electrode film prepared than coating SYSTEM Preparation discharge cases of the large current discharge performance increase of about 5% .
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