The battery module can be understood as the intermediate product of the battery and the pack formed by the combination of lithium-ion cells in series and parallel, and the addition of a single battery monitoring and management device. Its structure must support, fix and protect the cell, which can be summarized into three major items: mechanical strength, electrical performance, thermal performance and fault handling capability. Whether it can fix the position of the cell in good condition and protect it from deformation that damages its performance, how to meet the current-carrying performance requirements, how to meet the control of the temperature of the cell, whether it can be powered off in the event of a serious abnormality, and whether it can avoid thermal runaway Communication, etc., will be the criteria for judging the pros and cons of battery modules. For high-performance battery modules, their thermal management solutions have turned to liquid cooling or phase change materials.
The lithium battery module requires the battery to have a high degree of consistency (capacity, internal resistance, voltage, discharge curve, life).
The cycle life of a lithium battery module is lower than that of a single battery.
Use under limited conditions (including charging, discharging current, charging method, temperature, etc.).
After the lithium battery module is assembled into the system, it needs to be charged equalization, temperature, voltage and overcurrent monitoring.
The lithium battery module must meet the voltage and capacity requirements required by the design.
The lithium battery module is realized in two ways. One is through laser welding, ultrasonic welding or pulse welding. This is a commonly used welding method. The advantage is that the reliability is good, but it is not easy to replace. The second is to contact through elastic metal sheets. The advantage is that no welding is required, and the battery is easy to replace. The disadvantage is that it may lead to poor contact.
This is the first one.