A large Chinese battery manufacturer is suing two units of Vale, one of the world's largest mining companies, in a patent infringement case that highlights the growing number of Chinese companies using local courts to protect their interests.

Corun, a Shanghai-listed nickel processor and battery maker with close ties to the Chinese government, lodged a case with an intermediary court in its local jurisdiction in Hunan Province last month, claiming nearly Rmb90m ($13.1m) in damages from two Chinese subsidiaries of Vale Inco, the wholly owned Canadian subsidiary of Brazil-based Vale.