Introduces a soft package lithium battery module design points

Source: 2020 - 03 - 23 and clicks: the soft package lithium battery module design battery modules can be understood as the core product, is made of the lithium ion battery by series-parallel battery and battery pack, and equipped with single battery monitoring and processing equipment. Its structure is essential for support, fixed and maintenance of the battery, can be summarized as three kinds: mechanical strength, electrical, thermal and fault handling ability. Whether can completely immobilized cells of position and function of maintenance without damaging deformation, how to meet the requirements of current-carrying function, how to satisfy control the temperature of the cells, whether or not to turn it off when severe abnormalities, prevent the spread of heat is out of control, and so on, the standard to judge the quality of the battery module. High functional requirements battery module solution has been changed to surface or phase transition data. Soft package battery energy density single common three lithium battery packaging method, the simplest is high, but this layer module planning, the safety of the products is the most important task, can be said to be a part of the module structure. Module is the main component of soft package the key soft package of batteries, lithium battery module planning is a big gap between plan choice, above a relatively typical Chinese style, its basic components include: module control, please ( From the board of directors often said BMS) , battery monomer, electrical connection piece, plastic structure, cold plate, cooling pipe, two head clamp, to combine these components and fasteners. In addition to the collection of the function of the single cell and to provide certain pressure, at the ends of the module clamp is usually the fixed structure of the module planning at the top of the package. Structure planning structure planning requirements. The structure of the solid: feel resistance, fatigue resistance; Process control: without welding, welding, ensure the battery 100% without damage; Low cost: packaging production line of low cost automation, including loss of production equipment, production; Easy disassembling: the batteries are easy to maintain, repair, low cost, can be in a good position in the battery; Make the necessary heat barrier to prevent heat out of control and spread quickly. This step can also be considered in the packaging plan. It is known that professional cylindrical battery module and power is about 87%, power system model is about 65%. Soft package core module's power consumption is about 85%, the system of the power consumption of about 60%. Square battery module power is about 89%, the system module power is about 70%. Soft outfit battery of single energy density is higher than cylinder and a square has room for improvement, but the demand is higher, the module planning is difficult to control its security, these are structure planning problem. General module optimization method. To improve space utilization is the important way to optimize module. Power package can be modified by module and thermal management system planning to shorten battery spacing, and improve the utilization rate of the battery in the space. Another solution is to use the new data. For example, a bus ( Bus parallel circuit, usually made of copper plate) In power battery system instead of copper, aluminum, and module fasteners instead of high strength steel and aluminum metal plate data, it can also reduce the weight of the power battery. Hot plan the physical structure of the soft package battery determines it is not easy to broken, usually only shell can accept when the pressure is high enough, there may be a blast, and soft pack the battery internal pressure is very big, will be from the very beginning the edge of the aluminium plastic film pressure, leakage. There are also several batteries for use with flexible packaging cell structure, cooling effect is best. The famous representative of soft package of batteries, nissan's Leaf, the module structure is completely sealed, not to consider heat dissipation, no heat. This has to do with the Leaf frequent feedback capacity drops rapidly in the market. Obviously as people pursuit of high-performance electric cars, forcing flexible packaging battery also with automatic type heat conduction structure. At this point, the mainstream cooling mode has been changed to liquid cooling and cooling phase transition data. Phase change cooling data can be used in conjunction with liquid cooling, can also be under the condition of less demanding used alone. There is a more commonly used than domestic technology, pouring glue.