Chinese battery giant CATL has acquired a 3.7% stake in state-owned car manufacturer Chery, a move that could promote a long-term partnership between the two companies in battery making, according to information on the enterprise database site Tianyancha. The move comes at a time when a growing number of Chinese electric vehicle makers are diversifying their networks and developing batteries in-house to ensure a steady supply of the key components. In June, CATL formed a RMB 20 million ($2.9 million) joint venture with Kaiyi Auto, an EV brand in which Chery owns a 48% stake. CATL has also invested in other EV makers such as Geely’s Zeekr, Changan-backed Avatr, and Hozon. [Tianyancha, in Chinese]