圆柱型锂电池安全装置预测模型的建立及应用

Construction and application of prediction model for safety device of cylindrical lithium battery

在日常使用过程中,锂电池作为密封体系,其内部产气会造成壳体内部压力升高,导致其存在发生爆炸或其他次生灾害的安全隐患。圆柱型锂电池由于外壳耐压性强,因安全装置失效导致上述情况时的危险更加显著。为了降低这一风险,需要对锂电池安全装置的有效性进行检验。以圆柱型锂电池安全装置中电流切断装置及安全阀为研究对象,通过仪器平台测定某型号锂电池的断路触发值p_(I)及泄压触发值p_(V)。进而依据针对锂电池安全装置结构的X射线检测数据、阀片材料物理性质及能量守恒原理,建立基于焊接部最大拉断能量E_(max)的预测模型,提出用所计算的断路触发上限值p'_(I,max)与标准参考数据比对来判断电流切断装置有效性的预测方法,并利用同批次样品电池对该预测模型进行了验证。

In daily use,the gases generated in the lithium battery as a sealed system would cause the rise of its internal pressure,and further lead to the safety hazard of explosion or other secondary disasters.Because of the strong pressure resistance of the cylindrical lithium battery,the danger of the mentioned situation due to the failure of the safety device is relatively severe.In order to reduce the risk,it is necessary to verify the effectiveness of lithium battery safety devices.In terms of the current interrupt device and safety vent in the cylindrical lithium battery safety device,the cut-off trigger value and pressure release trigger value of a certain type of lithium battery were measured through instrument platform.Furthermore,on the basis of the X-ray detection data for the structure of safety device,the physical properties of the valve plate material and the principle of energy conservation,a prediction model based on the maximum tensile energy of welding area was set up.And the calculated maximum cut-off trigger value was compared with the standard reference data to determine the effectiveness of the current interrupt device.The prediction model was verified by using the same batch of battery samples.