###### Abstract
Thus, securing user trust in data privacy and security is a prerequisite for activating EV-related data utilization and value-added services. Blockchain technology is gaining attention as a potential solution to these data management issues, enabling secure sharing and utilization of EV operational data. Blockchain operates as a distributed ledger technology where multiple decentralized nodes jointly verify and reach consensus, characterized by high integrity, availability, and transparency [11]. Additionally, by storing data across multiple nodes, it eliminates single points of failure; thus, if EV black box data were managed on a blockchain, it could effectively prevent data tampering and ensure user control over data access, addressing information sovereignty issues. [PERSON] and [PERSON] [12] proposed a blockchain-based energy trading platform between electric vehicles and charging stations, where key operational data, such as vehicle identification, location information, and battery energy remaining, are transparently recorded on the blockchain, helping to prevent fraudulent charging and other malpractices. Moreover, since all transaction records are permanently stored in immutable blocks, it simplifies dispute resolution and accountability determination [13]. However, there are limitations to directly employing public blockchain platforms for managing EV data. The consensus process involving all nodes incurs high transaction costs and delays, which are not suitable for the real-time processing demands of large-scale EV data. For instance, Ethereum's average block creation time is about 13 s, with a transaction throughput of about 15 transactions per second [14]. Furthermore, the structural characteristic of making ledgers public to all nodes necessitates the adoption of additional encryption and access control techniques to ensure the confidentiality of black box data. Also, as the number of verifying nodes increases, so does the cost of consensus, making the unlimited expansion of consensus participants impractical. [PERSON] et al. [15] have pointed out scalability and privacy issues as major adoption barriers for public blockchains. In response, this study proposes a partially decentralized blockchain framework for the secure and efficient management of electric vehicle black box data. The proposed structure stores only encrypted hash values in the block to ensure confidentiality, while the consensus process involves only pre-approved nodes to enhance performance. These pre-approved nodes are selected through a rigorous vetting process conducted by a consortium of stakeholders, including electric vehicle manufacturers, energy providers, and regulatory bodies. The selection criteria for these nodes include factors such as reliability, computational performance, and compliance with security protocols. Reliability is evaluated based on the node's historical uptime and performance, computational performance is assessed by benchmarking the node's processing power and speed, and adherence to security protocols is verified through regular audits and security certifications. The vetting process also involves a series of tests and evaluations, including stress testing to measure performance under high loads, penetration testing to identify potential security vulnerabilities, and periodic audits to ensure ongoing compliance. By subjecting potential nodes to this thorough screening process, the consortium can ensure that only trusted and capable nodes are approved to participate in the consensus mechanism, thereby enhancing the overall security, reliability, and efficiency of the system. Additionally, a lightweight consensus algorithm that merges and compresses multiple transactions significantly reduces transaction cost burdens. The algorithm used in this framework is the Raft consensus algorithm, which is the default consensus mechanism in Hyperledger Fabric.