In response to the national dual-carbon strategy, it is imperative for steel enterprises to adopt new energy electric locomotives for internal transportation. As the core power source of electric locomotives, the performance of the battery system directly determines the operational efficiency and reliability of the locomotives. This paper focuses on the most widely used lithium iron phosphate batteries as the research object, and conducts research on key technologies such as system integration design, key parameter calculation, and real-time simulation model verification. The technical feasibility has been verified through practical application scenarios. The research results not only provide key technical support for the replacement of internal combustion locomotives with new energy in steel enterprises, but also have significant practical significance for promoting the green and low-carbon development of the steel industry.