We do a new Li-ion battery evaluation research on the effects of cell resistance and polariza- tion on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 ce...We do a new Li-ion battery evaluation research on the effects of cell resistance and polariza- tion on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 cells with different capacities and electrode materials are evalu- ated by measuring input and output energy which change with charge-discharge time and current. Based on the results of these tests, we build a model of energy loss in cells＇ charge- discharge process, which include Joule heat and polarization heat impact factors. It was reported that Joule heat was caused by cell resistance, which included De-resistance and reaction resistance, and reaction resistance could not be easily obtained through routine test method. Using this new method, we can get the total resistance R and the polarization parameter U. The relationship between R, η, and temperature is also investigated in order to build a general model for series of different Li-ion batteries, and the research can be used in the performance evaluation, state of charge prediction and the measuring of consistency of the batteries.展开更多
In order to solve the problem of property test of large flow-rate safety, the property parameter of safety valve test system was analyzed, and a device for property oflarge flow-rate safety valve test was designed.The...In order to solve the problem of property test of large flow-rate safety, the property parameter of safety valve test system was analyzed, and a device for property oflarge flow-rate safety valve test was designed.The device used accumulators as power source and a united function cylinder, which can realized the large flow-rate output for the test system.Analyzed the test data and made a particular research on the test device by testing different flow-rate safety valves;it verifies that the test device can be used tode-sign larger flow-rate safety valve test system and can make the flow-rate test and analysis and dynamic characteristics for the large-flow safety valve.展开更多
文摘We do a new Li-ion battery evaluation research on the effects of cell resistance and polariza- tion on the energy loss in batteries based on thermal property and heat generation behavior of battery. Series of 18650 cells with different capacities and electrode materials are evalu- ated by measuring input and output energy which change with charge-discharge time and current. Based on the results of these tests, we build a model of energy loss in cells＇ charge- discharge process, which include Joule heat and polarization heat impact factors. It was reported that Joule heat was caused by cell resistance, which included De-resistance and reaction resistance, and reaction resistance could not be easily obtained through routine test method. Using this new method, we can get the total resistance R and the polarization parameter U. The relationship between R, η, and temperature is also investigated in order to build a general model for series of different Li-ion batteries, and the research can be used in the performance evaluation, state of charge prediction and the measuring of consistency of the batteries.
基金Supported by China Coal Research Institute Innovation Item(2007CX06)
文摘In order to solve the problem of property test of large flow-rate safety, the property parameter of safety valve test system was analyzed, and a device for property oflarge flow-rate safety valve test was designed.The device used accumulators as power source and a united function cylinder, which can realized the large flow-rate output for the test system.Analyzed the test data and made a particular research on the test device by testing different flow-rate safety valves;it verifies that the test device can be used tode-sign larger flow-rate safety valve test system and can make the flow-rate test and analysis and dynamic characteristics for the large-flow safety valve.
