锂电池生产工艺

2025-03-26

锂离子电池是一个复杂系统，包括正极、负极、隔膜、电解液、流体收集器和粘合剂、导电剂等。参与的反应包括正极和负极的电化学反应、锂离子的导电、电子导电和热扩散等。锂电池的生产过程较长，涉及超过50个工序。

Lithium battery can be divided into cylindrical battery, square battery and soft package battery according to the form, and its production process has some differences, but overall, the lithium manufacturing process can be divided into the first step (pole manufacturing), the middle step (cell synthesis), the last step (forming and packaging). Because the safety performance of lithium ion battery is very high, the accuracy, stability and automation level of lithium battery equipment are highly required in the battery manufacturing process.

锂电设备是通过有序工序将阴极和阳极材料、隔膜材料、电解液等原材料进行制造的工艺设备，锂电设备对锂电池的性能和成本有显著影响，是影响因素之一。根据不同的工艺流程，锂电设备可以分为前段设备、中段设备和后段设备。在锂生产线上，前段、中段和后段设备的价值比例约为4:3:3。

第一步骤的生产目标是完成（正负）极板的制造。 

前道工序的主要工艺有：混合、涂布、辊压、切割、生产、冲压，所涉及的设备主要包括：混合器、涂布机、辊压机、切片机、生产机、冲切机等。

浆料混合（使用设备：真空混合器） is to mix positive and negative solid battery materials evenly and then add solvent to stir into slurry. Slurry mixing is the beginning of the previous process, is to complete the subsequent coating, roller and other processes prior to the foundation.

 涂布（设备：涂布机） is to stir the slurry evenly coated on the metal foil and dried into positive and negative pieces. As the core part of the previous process, the execution quality of the coating process profoundly affects the consistency, safety and life cycle of the finished battery, so the coating machine is the highest value of the equipment in the previous process.

 辊压（使用设备：辊压机） is to further compress the coated electrode sheet to improve the energy density of the battery. The smoothness of the roller – pressed rear electrode directly affects the processing effect of the post – sequence cutting process, and the uniformity of the active material of the electrode indirectly affects the performance of the cell.

切片（使用设备：切片机） is to continuously slice the wider coil of pole into a number of narrow pieces of required width. In the process of cutting, the pole slice encounters shearing fracture failure, and the level of edge after cutting (no burr, no buckling) is the key to evaluate the performance of the slicing machine.

制膜（设备：制膜机） includes welding pole lugs after cutting, pasting protective tape, wrapping pole lugs or using laser cutting to shape pole lugs, etc., for subsequent winding process. Die cutting (used equipment: die cutting machine) is the coating after the pole piece punching molding, for the subsequent process.

中段工序的生产目标是完成电池的制造。不同类型锂电池的中段工序在技术路线和生产线设备上存在差异。 

The essence of the middle process is the assembly process. Specifically, it is the orderly assembly of the (positive and negative) pole pieces made from the previous process with the diaphragm and electrolyte. Due to the different energy storage structures of square (roll), cylindrical (roll) and soft pack (layer) batteries, there are obvious differences in the technical route and production line equipment of different types of lithium batteries in the middle process. Specifically, the middle process of square and cylindrical battery mainly includes winding, liquid injection and packaging. The equipment involved mainly includes: winding machine, liquid injection machine, packaging equipment (shell feeding machine, groove rolling machine, sealing machine, welding machine), etc. The main process of the middle process of the soft pack battery is laminating, liquid injection and packaging. The equipment involved mainly includes laminating machine, liquid injection machine and packaging equipment.

绕线（使用设备：绕线机）被用于将制作工艺或绕制模切机制制作的极片卷入锂离子电池的电池单元中，主要用于方形和圆形锂电池的生产。绕线机可以细分为方形绕线机和圆柱形绕线机两类，分别用于方形和圆柱形锂电池的生产。与圆柱形绕线相比，方形绕线工艺对拉力控制的要求更高，因此方形绕线机更加复杂。

叠片（使用设备：叠片机） is the lamination of single pole pieces made in the die cutting process into lithium-ion battery cells, mainly used in the production of flexible battery. Compared with square and cylindrical cells, soft-clad cells have obvious advantages in energy density, safety and discharge performance. However, when the laminator completes a single stacking task, it involves the coordination of multiple sub-processes and complex mechanisms, so it needs to deal with complex dynamics control to improve the stacking efficiency. The speed of winding machine is directly related to the winding efficiency, and the method of efficiency enhancement is relatively simple. At present, the production efficiency and yield of laminated cell are not as good as those of wound cell.

液体注入机（使用设备：液体注入机） is the quantitative injection of battery electrolyte into the cell.

核心包装（使用设备：外壳机、槽滚机、密封机、焊接机） is to put the coiling core into the shell of the core.

后续工序的生产目标是完成成型和封装。

 通过中间工序，锂电池单元的功能结构已经形成，后续工序的意义在于对其进行激活，通过检测、分拣、组装，确保锂电池产品的安全使用和稳定性能。后续工序的主要过程包括：成型、容量分离、检测、分拣等。涉及的设备主要包括：充放电机、检测设备等。

成型（使用设备：充放电机） is to activate the cell through the first charge, during which effective passivation film (SEI film) is generated on the negative electrode surface to achieve the “initialization” of the lithium battery.

容量分离（使用设备：充放电机）, namely, “analysis capacity”, is to charge and discharge the cell in accordance with the design standard, in order to measure the electric capacity of the cell. Charge and discharge of the cell through the formation, capacitive process, so the charge and discharge machine is the most commonly used after the core equipment. The minimum working unit of charge-discharge machine is “channel”. A “unit” (BOX) is composed of a number of “channels”, and a number of “units” are combined together to form a charge-discharge machine.

测试（使用设备：测试设备）应在充电、放电和静置之前和之后进行；分类是根据测试结果按照一定标准对电池在成型和体积分离后的分类和选择。检测和排序过程的意义不仅在于消除不合格的产品，因为在锂离子电池的实际应用中，电池单元往往是并联和串联组合的，因此选择性能相似的单元有利于电池整体性能的最佳化。