Study On Energy Storage Density And Efficiency Of Potential Energy Storage Device

In recent years,facing the problem of environmental pollution and resource shortage challenges,energy saving and environmental protection have become one of the focus of world attention,energy recycling as one of the effective way of energy saving and environmental protection has attracted more and more attention of people.In modern society,various of storage devices has played an important role in various areas,and the energy storage density and energy storage efficiency of energy storage devices have become the focus of people's research.In this paper,the energy storage density and energy storage efficiency of potential energy storage devices are analyzed theoretically.First of all,in the paper,the factors affecting the energy storage density are analyzed in detail carried by analysising on the tensile spring and compression spring respectively and found that when the ratio of spring steel wire diameter d and spring outer diameter D1 is d/D1?(3/20,1/4),the mass storage density and volumetric energy storage density have the maximum valuet.Besides,the cycle of the energy storage and energy release of the spring is simulated and analyzed by simulating the Kano cycle of the heat engine.Considering the change of spring pressure and loss of friction loss,when the relationship between springstiffness coefficient K,load pressure F and lifting height H is k=F/H,thecomprehensive efficiency of spring energy storage is the highest and the highest energy storage efficiency is 50%.Secondly,the hydraulic system is the most common energy storage element bag accumulator as an example,studied under isothermal state energy storage accumulator in the main influencing factors in the process of storage and the change of pressure and volume were analyzed in the process,influence of accumulator storage factors the density and storage efficiency are analyzed in detail,the quality of storage energy density and volume energy density of energy storage,and the bag storage device in the highest efficiency of energy storage under isothermal condition.Generally,the overall efficiency of energy storage is not more than 60%.The super capacitor storage process is similar to that of the spring.The larger the initial value of the capacitor terminal voltage is,the lower the U0 can be used to store energy.The charging efficiency of the super capacitor is proportional to the initial value of the capacitor terminal voltage U0 and the ratio of the rated voltage U of the super capacitor.The discharge efficiency of the super capacitor is related to the ratio of the resistance to the resistance of the super capacitor.Finally,through the analysis and research of spring,accumulator and super capacitor energy storage,we found that the most important factor of energy storage efficiency is the initial state of energy storage device,and in general,the higher the initial value of the energy storage device,the higher the energy storage efficiency of the energy storage device.However,the larger the initial value is,the larger the volume required to store the same energy,so many storage devices have the problem of volume efficiency.It is found that the energy storage is not the same as the reserves.Energy loss exists in many energy storage devices.In the process of energy storage,many energy storage has the energy loss caused by the change of pressure.In the early stage of storage,energy will be lost because the system pressure is greater than the internal pressure of the energy storage device.In the later period of storage,the pressure of the system is less than the pressure in the energy storage device,so that the energy of the remaining part can not be stored in the energy storage device.When the energy is released,due to the pressure of the energy storage system is greater than the pressure of the system,energy will be lost.In the later period of energy release,the energy stored in the energy storage device can not be released due to the internal pressure of the energy storage device is less than the pressure of the system.Therefore,in order to make full use of the energy storage device stored energy,generally not to store the energy as a single power,but as the system pressure,in this way,the stored energy can be released 100 percent,and the energy storage efficiency can be improved.