Calendering device

Abstract

The invention provides a calendering apparatus. The calendering apparatus comprises a rolling mechanism, which comprises a first pressure roller and a second pressure roller arranged in parallel; a substrate, which is pasted with the first pressure roller and travels forward; a tape unwinding mechanism; and a tape, which is arranged on the tape unwinding mechanism, fed into the rolling mechanism by the tape unwinding mechanism, and adhered onto the substrate under the pressing of the first pressure roller and the second pressure roller. The tape unwinding mechanism comprises a tape unwinding shaft, a tape tension detecting component and a tape speed detecting component, wherein the tape wound on the tape unwinding shaft passes through the tape tension detecting component and the tape speeddetecting component and then enters the rolling mechanism; the rotation speed of the tape unwinding shaft is controlled by tension feedback detected by the tape tension detecting component so as to keep the tension of the tape constant; and the rotation speed of the second pressure roller is controlled by speed feedback detected by the tape speed detecting component so as to maintain the speed ofthe tape constant. Since the tension and the speed of the tape are constant, the weight of the tape entering the rolling mechanism per unit time is constant.

Description

technical field [0001] The invention relates to the field of calendering, in particular to a calendering device. Background technique [0002] Lithium-ion batteries are widely used in consumer electronics and electric vehicles due to their advantages such as high energy density, long service life, green and pollution-free. However, during the first charging and discharging process of a lithium battery, part of the lithium will be consumed due to the formation of the solid electrolyte film (SEI film), resulting in the loss of the positive electrode material lithium, and this irreversible loss of the first capacity directly leads to the loss of the battery capacity. At present, the lithium supplementation process of lithium-ion battery pole pieces is the key technology to increase capacity, and its core lies in calendering and lamination. Calendering is a process in which a lithium strip of 0.25mm to 2mm is rolled to form a lithium film of 0.002mm to 0.006mm and attached to t...

AI Technical Summary

Problems solved by technology

[0003] In the process of lithium supplementation, the consistency of the lithium supplement weight is an important parameter. If the lithium supplement is excessive, it is easy to cause problems of lithium precipitation and poor cycle performance in the battery cell.

Because it is difficult to prepare thin lithium ribbons in the existing technology, and the thickness fluctuation of lithium ribbon materials in the width and length directions is a major bottleneck for improving the consistency of lithium supplement weight

When the thickness of the lithium ribbon material fluctuates greatly (≥±20μm), the error in the thickness of the incoming material will easily lead to the accumulation of the lithium ribbon at the feeding place of the roller press, making it difficult to carry out the rolling process continuously and stably, resulting in the lithium ribbon rolled on the substrate. poor weight consistency

Images