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In recent years, with the rapid expansion of the new energy vehicle market, the demand for energy storage batteries has also been increasing at an accelerated pace. As a result, the demand for lithium-ion power batteries in China is surging as well, with power batteries becoming the driving force behind the growth of the lithium-ion battery industry. According to statistics, China’s lithium battery production in 2015 was 46.80 GWh ； It reached 62.34 GWh in 2016, a year-on-year increase of 33.2%. It is estimated that by 2020, the scale of China’s lithium-ion battery market will reach 170.55 GWH, with a compound growth rate of over 25% over the next 4 years. Manufacturing process for lithium-ion batteries: Production process for battery cells: Sorting process: Automatic sorting is carried out based on the performance parameters of the batteries as determined by testing instruments ； Automatic sorting equipment (simulation diagram). Manual sorting method: Ø Sorting of battery cells based on their appearance. Ø Inspection method: Full inspection. Ø Operation method: Manual inspection. Classification criteria: Requirement analysis – Since the performance and lifespan of power battery systems are directly related to the consistency of the individual cells within the system, this consistency includes aspects such as the quality of the cells, their dimensions, the appearance of their terminals, voltage, and internal resistance. The quality of battery cells is directly related to their capacity, and the system capacity is affected by the effect of low-capacity cells, which results in a reduction in the overall capacity. Differences in cell dimensions can affect the assembly of battery modules. For example, large differences in cell thickness can impact the fixing of the battery module in the thickness direction, while significant variations in cell height can affect the welding of the cell terminals later on. Terminals of cells with lower heights may be at a distance from the cell connection strips, leading to failed welding or excessive welding stress; this stress poses a risk of breakage during subsequent use. Poor appearance of the cell terminals, such as damage, cracks, dents, rust, or other impurities, can affect the subsequent welding process of the cells, leading to poor welds, connection failures, and other safety hazards. Poor consistency in cell voltage and internal resistance, due to the short-board effect of batteries, leads to a decline in the overall performance and lifespan of the battery system. In summary, it is essential to control the quality, size, terminal appearance, voltage, and internal resistance of battery cells. At present, most battery system manufacturers in the industry control the voltage and internal resistance of these cells, but they do not fully control their quality, size, and terminal appearance. Moreover, all measurements are carried out manually, which results in significant measurement errors and low efficiency. In light of the above, Linghou Robot has developed its own solution (using robotic arms to carry out the automatic sorting of battery cells) in order to increase the degree of automation in measuring various parameters of battery cells, reduce errors resulting from manual measurements, and lower the costs associated with manual labor. The plan describes the automatic cell sorting section, which uses a six-axis robot for handling and sorting. There are four types of defective products identified: those with faulty barcodes, incorrect thickness, abnormal weight, or failed OCV tests. The qualified products are placed in customer-standard containers, and scanning these containers allows for the identification of any defects. The appearance of the equipment is as shown in the figure below: 1. System framework – Diagram of the internal structure of the equipment; 2. Process flow – System configuration includes robotic arms, material handling mechanisms, and weight sensors. Technical specifications: Precision: Ø Resistance: ±0.5% rdg. ±5dgt; Ø Voltage: ±0.1% rdg. ±3dgt. Efficiency: 0.3S/cell. Example photos are available. Advantages: The comparison table showing the improvements resulting from automation is as follows: Sequence, Production status, Equipment/persons, Process, Labor comparison, Product quality/system control. 1. Current production status: Manual labor for cell handling; manual labor for inspection and sorting. Weak stability, making it difficult to ensure consistent product standards. 2. Production status after improvement: Robots for cell handling; no manual labor required. Easy system switching, ensuring consistent product quality. Robots also handle inspection and sorting. Lithium-ion batteries are one of the three core components of new energy electric vehicles. Today, competition within the same industry is extremely fierce. To stand out in future market competition, traditional assembly processes and production methods will inevitably be phased out. After all, the constant requirement of vehicle manufacturers, who are the main customers of batteries, is for greater safety, reliability, and consistency. Intelligent and automated production methods have become important criteria for vehicle manufacturers when evaluating suppliers’ products ； Therefore, it is highly necessary to improve the automation level of power battery module assembly.