In wireless rechargeable sensor networks (WRSNs), how to perform reasonable charging scheduling for MCs with limited capacity to ensure efficient network operation remains one of the keys. This paper proposes an adaptive threshold partial charging strategy to achieve efficient energy allocation by dynamically adjusting the charging threshold of sensor nodes. The strategy first clusters the network and determines the charging order and charging thresholds based on the remaining energy of the nodes in the network, the importance of the nodes, and the distance from the MC in terms of each cluster, thus avoiding unnecessary charging processes. The experiment proves what is proposed method can significantly improve the number of surviving nodes, the total remaining energy of nodes, time when the first node is hibernated, and provides a solution to the uncertainty problem and the multi-MC collaboration problem in charging scenarios.