摘要：100 pieces of 26650-type Lithium iron phosphate（LiFePO4） batteries cycled with a fixed charge and discharge rate are tested, and the influence of the battery internal resistance and the instantaneous voltage drop at the start of discharge on the state of health（SOH） is discussed. A back propagation（BP） neural network model using additional momentum is built up to estimate the state of health of Li-ion batteries. The additional 10 pieces are used to verify the feasibility of the proposed method. The results show that the neural network prediction model have a higher accuracy and can be embedded into battery management system（BMS） to estimate SOH of LiFePO4 Li-ion batteries.

摘要：In this paper, the hybrid electric vehicle braking process is researched, by using variables co.sists of HEV speed, motor speed, and state of charge established, fimctions of mechanical braking force, regenerative braking force and efficiency of energy reco.ery are co.structed, and the co.trol goal is to maximization the energy reco.ery efficiency. Under the feedback co.trol strategy, with the co.strain co.dition of braking strength and braking stability, co.bining experiments in ADVISOR, in different experiments of different working co.ditions, we can see that in UDDS Cycle, the regenerative braking efficiency is the best. What＇s more, co.pared with strategies in ADVISOR, strategy proposed in this paper is obviously better.