Abstract:

In recent years， many NEV （new energy vehicle） manufacturershave collaborated with battery suppliers to vigorously promote the technology of NEV product. For example， in 2017， BMW signed a $117 million battery-production contract with Contemporary Amperex Technology Ltd （CATL）， the world largest battery manufacturers. After that， the CATL has signed several development and supply contracts with NEV manufacturers （such as， Toyota， Chang an et al.）. However， the stability of collaboration is challenged by the innovation cost， opportunity behavior and conflicts interest， which lead to a low innovation effectiveness.In view of the difficulties of the manufacturers and distrust with the suppliers in NEV supply chain， the shareholding strategy is introduced into the NEV supply chain. Considering whether the shareholding strategy is introduced and who holds share in the investments， the game theory and operational research optimization methods are embraced to develop the mathematical models for different scenarios. Firstly， a game model is built in which the manufacturers and supplier do not collaborate in innovation and this model is treated as a benchmark model for comparison. Secondly， a game model is adopted in which the battery supplier holds shares of NEV manufacturer. Then， a game model is developed in which the NEV manufacturer holds shares of battery supplier. Finally， the situation of NEV manufacturer and battery supplier hold share with each other is designed.In order to draw some valuable conclusions， the models are analyzed through numerical analysis， focusing on the relationship between the shareholding strategy and decision-making and innovation activities.Our findings show that the decision of boththe NEV manufacturersandbatterysuppliers is affected by the proportion of shares. In the longitudinal shareholding strategy model， the battery endurance and vehicle quality are positively affected bythe proportion of shares. Besides， both the wholesale price of the battery and the selling price are positively affected bythe proportion of supplier’s shares，and are negatively affected bythe proportion of NEV manufacturer’s shares. Furthermore， it is found that the supplier prefers the cross-shareholding strategy since he can gain more profit than that under the other shareholding strategies. However， for the manufacturer， he chooses the cross-shareholding strategy only when his shareholding ratio is low and the supplier's shareholding ratio reaches a certain level.

Key words: shareholding strategies, battery life, vehicle quality level, supply chain innovation