A Novel Tension Control System of Square Lithium Battery Laminated Machine

Background: To the problem that the traditional square laminated machine with passive unwinding control strategy makes the tape speed periodical changing in reciprocating motion and not achieve a good tension control, a novel unwinding system and control algorithm are presented to improve the efficiency and quality of such equipment. Methods: Compared with the traditional passive unwinding control system, the novel tension control system adds an active compliance mechanism. After obtaining the motion relationship between the compliance device and the laminated motion platform through building the complex system mathematical model, the laminated machine tension control is equivalent to a spatial trajectory tracking control, and multi-axis synchronous coordinated control algorithm is used to control their relative motions, and a cross-coupling control in multi-axis coordinated motion is presented to decrease the synchronous error of the two linear servo motors, which are the compliance device driving motor and the laminated motion platform driving one. Without tension sensor, however, good tension control is obtained only by position tracking control. Results: Based on the proposed approaches and novel unwinding mechanism, the tension control was examined on an experimental square lithium battery laminated machine and results of the experiments performed with the experimental setup demonstrated the effectiveness of the proposed approach. Conclusion: Without a tension sensor, good tension control is obtained only by position tracking control in the novel unwinding system, and the production quality and efficiency of the lithium battery laminated machine are improved.