Background
Shenzhen NTI Robot convened a team of skilled professionals to tailor a comprehensive solution of intelligent logistics for lithium battery production to meet a set of practical requirements from its client Sunwoda Electronics. By employing AGVs, NTI is able to adapt to market changes swiftly and cater for specific needs, boosting production efficiency for its clients.
Featured AGV system
The AGV system NTI designed comprises four types of laser guided AGV (as shown in the pictures below): side roller conveyor AGV, roller conveyor AGV, forklift AGV, and chain conveyor AGV, which are deployed across various stages of lithium battery production including formation and grading, assembly and baking, battery cell storage, and modular line. Different AGV types are utilized for transporting and storing diverse battery materials to meet the specific requirements of customers at different stages of battery production.
Technical Challenges
- Exacting requirements for safe operations of AGVs. The aisles of the formation segment are narrow and long, with a width less than 3m and a length exceeding 100m, which places stringent restrictions on AGVs’ turning radius and payload. AGVs have to transport in triplets of small frame pallet batteries, amid a substantial overall transportation volume within a given time period, crying for a highly-efficient AGV operations.
- Intricate design of the complex system. During the transportation process of assembling the baking section, the system design is put to the test due to the stringent requirements for temperature, humidity, and atmospheric pressure for the battery, as well as its susceptibility to air exposure and dust contamination.
- High precision requirements and safty hazards. The battery cell warehouse features multiple levels of tall racks with a load capacity of approximately 1,400KG per level. The AGV’s lifting height must reach at least 4.4 meters, and the goods are stored in close proximity. High precision is required under heavy load conditions, resulting in elevated overall risk.
- Cross-floor transport capability. For the modular line,the AGVs must collaborate with the lift to facilitate inter-floor transportation from the second floor to the first floor, and it should have the capability to transport trays of various types and sizes.
Solutions
- For the formation segment,the AGVs are designed to be lightweight and compact, meeting the requirements for efficient goods transportation. Narrow aisles are equipped with dual-channel elevators to optimize space utilization and accommodate bi-directional operation within the aisle. Additionally, the incorporation of side rollers is aimed at reducing loading and unloading times at the platform.
- The battery transportation of assembly and baking warehouse requires specific temperature and humidity conditions. To effectively shield against dust and protect the batteries during transit, as well as to accommodate manual sample testing, the protective face shield has been optimized with a transparent acrylic board protection mechanism, for which corresponding technical patents have been obtained.
- The battery cell warehouse is equipped with three-tiered racks and utilizes stacking AGVs with a maximum load capacity of 1400KG. The AGV’s lifting height exceeds 4.4 m and employs a 3-stage mast for elevation. Various safety detection devices are installed on the stacking AGV in the battery cell warehouse to ensure operational safety and prevent collisions during loading and unloading processes.
- The large and long chain of the conveyor AGV for module line is accommodated by the installation of multiple cargo detection sensors, enabling adaptation to various types of battery modules and pallet lengths, while also facilitating cross-floor transportation between the second and first floors in conjunction with a hoist.
- The AGV utilizes laser SLAM navigation, supplemented by a limited number of reflectors to constitute the entire navigation system. This configuration ensures minimal ground alteration or damage, while also providing highly flexible AGV routes and achieving high positioning accuracy of up to ±5mm.
Highlights of the products
- The AGV for battery cell warehouse utilizes a 3-stage mast structure to meet height requirements and incorporates multiple layers of inventory occupancy detection for enhanced safety. Additionally, it is equipped with a high-level detection system for the warehouse electric door, which is integrated with the electric door to achieve full automation of battery cell storage.
- The AGV utilizes 24V maintenance-free LFP battery for automatic charging, providing convenience and ensuring safe and rapid charging through signal confirmation between the charging machine and AGVs.
- The AGV utilizes a combination of laser, photoelectric, and infrared collision avoidance methods, along with safety edge, to establish a comprehensive collision avoidance system that effectively mitigates various potential hazards during operation.
What benefits to expect from the products?
The system is capable of handling approximately 120,000 battery units, 600 pallets of cell cores, and 400 pallets of module storage and transportation on a daily basis, which results in a reduction of 10 forklift operators while concurrently lifts transportation efficiency by 30%. The payback period is estimated to be around 3 years.
The NTI AGV Intelligent Logistics System has been successfully integrated with the client’s MES and WMS. It adopted the latest AGV control system and optimized the scheduling management algorithm, along with corresponding optimization design for mass AGV fleet dispatch, effectively enhancing system stability and efficiency.
The project addresses issues related to non-standardized on-site goods stacking, placement, and labeling, as well as challenges such as high labor intensity in on-site goods handling and distribution, growing demand for labor, frequent interaction between personnel and forklifts, significant traffic safety hazards, and numerous uncontrollable factors in forklift operation and positioning. It enhances production efficiency by enabling automated material handling and information management for warehouse operations while mitigating manual handling difficulties, low efficiency in handling tasks, and elevated risks associated with manual material handling.
