The state of health (SoH) of electric vehicle (EV) batteries is important for the EV owner and potential buyer of second hand EVs. The incremental capacity analysis (ICA) has by several researchers proven to be a promising SoH estimation method for lithium-ion batteries. However, in order to be practical useable, the method needs to be feasible on a pack or EV level and not only on an individual cell level. Therefore, the purpose of this article is to demonstrate the feasibility of the ICA method on real EVs. Nickel manganese cobalt (NMC) cells used in BMW i3 EVs and lithium manganese oxide (LMO) used in Nissan Leaf EVs have been tested both on the cell level and on car level. The results are consistent and the characteristic peaks and valleys of the ICA on car level match with the same on cell level. A root-mean-square error of 1.33% and 2.92% has been obtained for the SoH estimation of the NMC and LMO type, respectively. It is therefore concluded that the ICA method is also applicable to the car level for battery SoH estimation.

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电动汽车增量容量分析在电池健康状态评估中的应用

电动汽车（EV）电池的健康状态（SoH）对于EV拥有者和二手EV的潜在购买者而言非常重要。几位研究人员证明了增量容量分析（ICA）是一种有前途的锂离子电池SoH估算方法。但是，为了切实可行，该方法需要在电池组或电动汽车级别上可行，而不仅是在单个电池单元级别上可行。因此，本文的目的是证明ICA方法在实际电动汽车上的可行性。BMW i3电动汽车中使用的镍锰钴（NMC）电池和日产Leaf电动汽车中使用的氧化锰锂（LMO）已在电池级别和汽车级别进行了测试。结果是一致的，并且在汽车水平上ICA的特征峰和谷与在细胞水平上相同。均方根误差为1.33％和2。对于NMC和LMO类型的SoH估计分别获得了92％。因此可以得出结论，ICA方法也适用于汽车液位的SoH估算。