Power Battery System Test
The power battery system is the energy storage unit of new energy vehicles. The power battery system of electric vehicles mainly includes three parts: power battery energy storage system, power battery management system and power battery charging system. Power batteries are the core of new energy vehicles, providing the entire vehicle with electrical energy to drive the vehicle.
This article takes the lithium-ion power battery system as an example to systematically introduce the power battery system test methods in three aspects: electrical performance, lifespan and safety.
(1)Electrical performance test
Power battery system testing includes capacity, energy testing, power testing, etc. Generally, power battery system charging and discharging equipment is used to realize the charging and discharging of the power battery system. The large-scale high and low temperature alternating humidity and heat test chamber can conduct the weather resistance test of the power battery system. The electrical performance test of the power battery system mainly includes capacity test, energy test and power test.
Power battery system charging and discharging equipment: It can act as a power source to charge the power battery system, and can also act as a load to discharge the power battery system. By controlling the battery management system to engage the internal relay of the power battery management system, the charging and discharging equipment can realize charging and discharging of the power battery system by controlling the loop current or terminal voltage according to the set program.
High and low temperature alternating humidity and heat test chamber: Automatically adjust the temperature and humidity working conditions according to the requirements, provide environmental conditions for power battery system testing, ensure that the temperature and humidity of the power battery system are within the range of test requirements, and take into account the role of flame retardant and explosion-proof.
(2) Life test
The life of the power battery system is affected by many factors, including ambient temperature and humidity, charging method, driver's operating habits and frequency of use, etc. Carry out a power battery system cycle life test and record the discharge capacity and electric energy attenuation of the battery system through continuous charge and discharge cycles, which can simulate the actual working process of the vehicle and the reduction in driving range caused by capacity and energy attenuation.
(3) Safety test
In recent years, with the continuous expansion of the pure electric vehicle market, many safety issues have been exposed. Compared with other components, the power battery system has higher risks, and it is particularly important to conduct power battery system safety tests.
GB 38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles" stipulates a total of 16 safety test items for power battery systems, including: vibration, mechanical impact, simulated collision, extrusion, heat and humidity cycle, water immersion, external fire, and thermal diffusion , temperature shock, salt spray, high altitude, over-current protection, over-temperature protection, short-circuit protection, over-charge protection, over-discharge protection.
