Pole piece roll-forming method and device

Abstract

The invention provides a pole piece roll-forming method and a pole piece roll-forming device. The method comprises the steps that: slurry is coated on the surface of a current collector, such that a pole piece is prepared; the pole piece is bake-dried in a baking oven of a coating machine; the dried pole piece is delivered into a rolling mechanism, and rolling is carried out, wherein the bake-drying treatment and the rolling of the rolling mechanism are carried out in the baking oven of the coating machine. The pole piece roll-forming device is used for implementing the pole piece roll-forming method. The device comprises a coating machine baking oven used for carrying out the bake drying treatment upon the pole piece formed by the current collector coated with the slurry, and the rolling mechanism used for rolling the dried pole piece. The rolling mechanism is arranged in the coating machine baking oven. With the pole piece roll-forming method and device, battery core electrochemical properties can be improved, and pole piece thickness rebound can be reduced. In industrial production, the method and the device have the advantages of simple operation and easy realization.

Description

technical field [0001] The invention relates to a pressure forming technology, in particular to a pole piece roll forming method and device. Background technique [0002] As the most representative energy storage device in the field of new energy, lithium-ion batteries occupy an irreplaceable position in power supply devices for mobile electronic products. Especially in the field of power batteries, there are higher requirements for high-rate charge-discharge performance and thinner thickness of batteries. [0003] At present, the rolling of the anode sheet is a method to obtain a certain compaction density: at room temperature, the round roller mechanism is used to adjust the gap and pressure of the upper and lower rollers, and the anode sheet is rolled to make the graphite particles squeezed and piled up, and the gap between the particles is reduced. Small, the compaction density increases, when the pole piece is compacted to a certain thickness, the compaction density re...

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Problems solved by technology

However, there are two disadvantages in obtaining pole pieces by this method; 1) During the coating and baking process, the binder is very easy to float to the surface of the pole piece, and after cold pressing and compaction, the pole piece forms a dense binder mixed with graphite layer, which affects the infiltration of the electrolyte, reduces the electrochemical performance of the battery, and causes the impedance to increase when the battery is charged at a high rate, and the rate performance and low-temperature cycle performance are deteriorated; 2) Roll the pole piece at room temperature Pressure, the adhesive will have a slow stress release process, reflected in the rebound of the thickness of the pole piece, resulting in an increase in the thickness of the pole piece, increasing the possibility of deformation of the battery cell

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