The battery management system (BATTERY MANAGEMENT SYSTEM) is the link between the battery and the user, and the main object is the secondary battery. The secondary battery has the following disadvantages such as low storage energy, short life, serial and parallel use problems, safety of use, difficulty in estimating battery power, and the like. The performance of the battery is very complicated, and the characteristics of different types of batteries vary greatly. The battery management system (BMS) is mainly to improve the utilization of the battery, prevent overcharging and overdischarging of the battery, prolong the service life of the battery, and monitor the state of the battery. As battery management systems evolve, additional features will be added. Generally speaking, the electric vehicle battery management system must realize the following functions: Firstly, accurately estimate the state of charge of the power battery pack, that is, the remaining battery power, and ensure that the SOC is maintained within a reasonable range to prevent overcharge or overdischarge. The damage of the battery, so as to predict at any time how much energy is left in the energy storage battery of the hybrid vehicle or the state of charge of the energy storage battery. Secondly, the working state of the power battery pack is dynamically monitored. During the charging and discharging process of the battery, the terminal voltage and temperature, the charging and discharging current and the total voltage of the battery pack of each battery in the battery pack of the electric vehicle are collected in real time to prevent overcharging or overdischarging of the battery. At the same time, the battery condition can be given in time, and the problematic battery can be selected to maintain the reliability and high efficiency of the entire battery operation, and the realization of the remaining battery estimation model becomes possible. In addition, it is necessary to establish a usage history file for each battery to provide data for further optimization and development of new types of electricity, chargers, motors, etc., and to provide a basis for offline analysis system failure. Finally, the balance between the cells is achieved, that is, the cells are uniformly charged, so that the cells in the battery pack reach a state of equilibrium. Equilibrium technology is the key technology of a battery energy management system that the world is currently researching and developing. During the injection molding process, when the molten plastic meets in the form of multiple strands in the cavity due to the holes in the insert, the areas where the flow rate is discontinuous, and the area where the filling material flow is interrupted, a linear weld seam is produced because it cannot be completely fused. In addition, when the gate injection molding occurs, a weld seam will also be formed, and the strength and other properties of the weld seam are poor. The main reasons are as follows: Pvc Injection,Precision Plastic Injection Mould,Oem Plastic Injection Crate Mould,Plastic Injection Mould Suzhou Dongye Precision Molding Co.,Ltd. , https://www.dongyeinjectionmolding.com
Processing:
The injection pressure and speed are too low, and the barrel temperature and mold temperature are too low, resulting in premature cooling of the molten material entering the mold and the appearance of weld seams.
When the injection pressure and speed are too high, injection will occur and weld seams will appear. The speed should be increased, and the back pressure should be increased to reduce the viscosity of the plastic and increase the density. Plastics should be dry well, recycled materials should be used sparingly, and weld seams may occur if the amount of release agent is too much or the quality is not good. Reduce clamping force and facilitate exhaust.
2. Mould:
If there are too many gates in the same cavity, reduce the gate or set it symmetrically, or set it as close as possible to the weld seam. The exhaust at the weld seam is poor, and an exhaust system should be set up. The sprue is too large, the size of the gating system is improper, and the gate is opened to prevent the melt from flowing around the insert hole, or use as few inserts as possible. If the wall thickness changes too much, or the wall thickness is too thin, the wall thickness of the workpiece should be uniform. If necessary, a fusion well should be opened at the fusion seam to separate the fusion seam from the workpiece.
3. Plastic aspects:
Lubricants and stabilizers should be appropriately added to plastics with poor fluidity or heat sensitivity. Plastic contains a lot of impurities, if necessary, replace the plastic with good quality.