Long cycle life

What affect the cycle life of the vapor lithium battery?

1, Material components of the lithium battery. The anode material is part of the most components of lithium ion battery. The anode material is usually included ICR(lithium cobalt acid), NCR(lithium cobalt oxide), IMR(lithium manganese oxide), INR(ASP cathode material) and IFR(lithium iron phosphate). The cathode material of lithium battery is Carbon.

2, Moisture. Too much water will interact with the electrode material and destroy that structure. It will affect the cycle life of the batteries. Meanwhile, too much water is not benefit for the formation of SEI films. But it is impossible to remove the moisture completely. Of course, a certain amount of moisture can make sure the performance of the batteries to a certain extent.

3, Anode and cathode compaction density of the battery. Higher compaction density can increase the energy density. But it will have a negative effect on the cycle life. In theory, the higher the compaction density, the destruction of the material structure gets bigger. But the structure of the material is the basis for the cycle life. What’s more, too high compaction density cannot ensure enough preserving electrolytes capacity. But preserving electrolytes capacity is the base to help the battery to keep circulation.

4,Testing conditions. During the testing, the charge/discharge rate, cut off voltage, the end of charge current, over charge/discharge, the temperature of the testing room etc will affect the testing result. 

5, Access to negative material. Except the influence of the irreversible capacities and the density deviation of the coating films, excess on negative material also will affect the cycle life of the batteries. For lithium batteries, the negative material usually uses graphite carbon. If the graphite cathode is not enough, the battery cell may cannot analyze the lithium. After several times of circulation, the structure of the cathode will be heavily destroyed and cannot receive the lithium ion completely and analyze them which will cause the capacity of sagging too early.

6,The density of the coating films. For batteries with the same capacity, the same discharge rate and the same material, lower the density of the coating films means increasing a layer or multilayer winding or laminated layers. The increasing coating films will absorb more electrolytes and ensure the circulation. 

7, Electrolytes content. There are three reasons that the electrolytes will affect the cycle life of the batteries. The first, the electrolytes fluid injection shortage. The second, electrolytes immersion not sufficient. Third, electrolytes was completely consumed with the battery cell circulating. The micro-expression of the suitability between the electrolytes and cathode is the formation of compact and stable SEI films. On the one side, incomplete SEI films will consume electrolytes because it can’t effectively prevent the cathode and the electrolytes has side-reaction. On the other hand, SEI films will rebuild on the position with flaws which will consume the Reversible lithium source and electrolytes. No matter for the battery cell which has cycled thousands of times or just a few times, if the electrolyte is adequate before cycle while completely consumed after cycle, increasing the electrolyte inventory may improve the cycle life.