Spatiotemporal Evolution of a New Energy Vehicle Enterprise’s Investment Layout from the Industrial Chain Perspective: A Case Study of BYD

Exploring the spatiotemporal evolution of investment layouts of new energy vehicle (NEV) enterprises is important for understanding NEV industrial chains and their spatial organization. Taking BYD as a case study, this study adopts an industrial chain perspective and integrates Sankey diagrams with spatial analysis methods to examine the evolution of BYD’s investment layout from 2015 to 2025. The results reveal that (1) the number of subsidiaries invested by BYD increased dramatically from fewer than 50 in 2015 to 737 in 2025, with 2021–2025 representing the most rapid expansion period. BYD gradually developed an industrial chain structure characterized by the numerical dominance of sales-related enterprises, while capital investment remained concentrated in manufacturing segments. (2) During 2021–2025, BYD’s investment layout exhibited a northeast–southwest spatial orientation, with the investment center continuously shifting northeastward. The spatial distribution evolved from a dispersed pattern toward stable aggregation along the principal axis. (3) By 2025, BYD’s investment layout had become relatively stable, although significant differences existed among industrial chain segments. The Market and Sales (M&S) segment exhibited the widest spatial coverage. The Vehicle Manufacturing and Rail Transit (VM&RT) segment demonstrated a dual-core pattern dominated by the Pearl River Delta (PRD) and Xi’an, Shaanxi Province. The Battery and Materials (B&M) segment presented a polycentric balanced pattern, with three primary cores located in the PRD, Guangxi, and Chongqing, accompanied by multiple secondary cores including Zhejiang and Anhui. In contrast, both the Components and Semiconductors (C&S) and Services and Finance (S&F) segments exhibited a single-core pattern dominated by the PRD. (4) Significant differences existed in the intensity of spatial dependence among BYD’s industrial chain segments. The spatial distributions of the entire industrial chain and the M&S segment both exhibited significant positive spatial autocorrelation, with highly consistent clustering patterns. Although the VM&RT segment did not pass the significance test, small-scale High–High clustering patterns were still observed locally. These findings provide empirical evidence for understanding the spatial organization of the NEV industry and BYD’s investment expansion.