What is a positive electrode? The cathode plate is an...
Lithium iron phosphate battery electrode section process
Lithium iron phosphate battery (LiFePO4) is widely used because of its superior safety performance and long cycle life. In the manufacturing process of battery, the electrode segment technology is a crucial link, which directly affects the performance and quality of battery. The electrode segment process mainly includes four steps: mixing, coating, rolling and slaying/die-cutting. The following will introduce the specific process of these four steps and their importance one by one.
Slurry mixing is the first step of the electrode segment process, and its main purpose is to fully mix the various materials required for the battery to form a uniform slurry. The details are as follows:
Raw material preparation: high purity lithium iron phosphate (LiFePO4) is prepared as the positive electrode material, and the negative electrode is usually graphite. At the same time, an appropriate amount of conductive agent (such as carbon black) and adhesive (such as polyvinylidene difluoride, PVDF) are added. The choice and proportion of these materials have a direct impact on the performance of the battery.
Slurry preparation: put the above materials into a mixer in a certain proportion, add the appropriate amount of solvent (such as NMP, N-methyl pyrrolidone), and stir through a high shear mixer. The mixture was stirred for several hours until the slurry reached the desired viscosity and uniformity. This process is the basis for ensuring that the subsequent steps proceed smoothly.
The coating procedure is to evenly coat the paste on the prepared aluminum foil (for the positive electrode) and copper foil (for the negative electrode) to form the electrode layer. The coating process is as follows:
Coating method: The commonly used coating technology includes scraping, rolling and spraying. Adjust the speed and pressure of the coating machine as needed to ensure uniform thickness of the coating layer.
Coating effect: The coated electrode material needs to achieve the required thickness (usually between tens of microns to hundreds of microns), and the uniformity of the thickness is crucial to the discharge performance and energy density of the battery. A thicker electrode layer can improve the energy density of the battery, but it may also increase the internal resistance and affect the charging and discharging efficiency, so it needs to be strictly controlled.
Rolling is a key step in the electrode segment process, and its main purpose is to further improve the density and mechanical strength of the electrode material. The rolling process is as follows:
Equipment setup: The coated electrode is sent between two parallel rollers through the roller press. Adjust the pressure and speed of the roller press according to the characteristics of the material and the process requirements.
Pressing effect: During the roller pressing process, the electrode material is squeezed to make it more compact in the internal structure, ensuring the conductivity and ion conductivity of the electrode layer. This process helps to improve the cycling performance and charging and discharging efficiency of the battery.
The final step is slitting or die-cutting, where the coated and roller treated electrode sheet is cut into a suitable size for assembly. The process is as follows:
Cut preparation: Determine the final size of the electrode sheet according to the design requirements of the battery. The shape and edge quality of the electrode should be considered in the cutting process to ensure the smooth progress of the subsequent assembly.
Cutting equipment: high-precision cutting machine is used to cut the electrode piece to ensure that the size of each electrode piece is consistent and the edge is smooth. Die-cutting is cutting on specific patterns to meet the needs of special shape batteries.
Cutting quality check: After the cutting is completed, the electrode pieces are checked for quality, including size, thickness and appearance, etc., to ensure that each electrode meets the standards and is ready for assembly.
conclusion
The electrode segment process is an important link in the manufacturing of lithium iron phosphate battery, which includes four key steps: mixing, coating, rolling and slitting/die-cutting. Each step has a profound impact on the performance and quality of the battery. By controlling various process parameters to ensure the uniformity, thickness and density of the electrode material, the energy density and service life of the battery can be significantly improved. With the development of battery technology, the optimization of electrode process will become the key to improve the overall performance of the battery.
Home energy storage product series
A lithium battery pack for home energy storage systems, which is compatible with solar panels and the sun The inverter can work together with the power grid to power household appliances, and it can also be used as a For off grid systems.
Extended reading
The process flow of vertical section of lithium ion battery pack
The process flow of vertical section of lithium ion battery...
THE ESSC Brand promise
Global supply
Our products sell well all over the world, covering many countries and regions, through the global logistics network, to provide customers with convenient purchasing experience.
Rigorous quality
We adhere to the highest quality control standards to ensure every product meets industry regulations and customer expectations, earning trust through consistent excellence.
Excellent service
With a customer-centric approach, we provide prompt responses, professional support, and personalized services, aiming to deliver the best user experience and long-term value.