什么是钠电池的高温性能测试？

What is the high temperature performance test of sodium batteries?

钠电池的高温性能测试是评估钠离子电池在高温环境下的工作稳定性、容量保持率、循环寿命及安全性能的核心标准化测试，是钠电池产品认证、场景适配性验证的关键环节。测试通常在恒温恒湿试验箱中进行，核心测试维度包括：一是高温容量保持率测试，在45℃-60℃的高温环境下，按标准倍率完成充放电循环，测试电池的实际放电容量与常温容量的比值，评估高温环境下的储电能力衰减情况；二是高温循环寿命测试，在高温环境下连续完成数百至数千次充放电循环，监测电池的容量衰减速率、内阻增长情况，评估长期高温使用的稳定性；三是高温热稳定性测试，通过逐步升温的方式，测试电池的热分解温度、热失控触发阈值，评估高温环境下的安全风险；四是高温倍率性能测试，在高温环境下进行不同倍率的充放电测试，评估大电流充放电下的性能表现。主流商用钠电池的高温性能测试标准要求，45℃环境下循环3000次后容量保持率不低于80%，热分解温度不低于300℃，确保在高温户外、机房、热带地区等场景的稳定使用。

The high temperature performance test of sodium batteries is a core standardized test to evaluate the working stability, capacity retention rate, cycle life and safety performance of sodium-ion batteries in high temperature environments, and is a key link for product certification and scenario adaptability verification of sodium batteries. The test is usually carried out in a constant temperature and humidity test chamber, and the core test dimensions include: First, the high temperature capacity retention rate test, which completes the charge-discharge cycle at a standard rate in a high temperature environment of 45℃-60℃, tests the ratio of the actual discharge capacity of the battery to the normal temperature capacity, and evaluates the attenuation of the power storage capacity in a high temperature environment; Second, the high temperature cycle life test, which continuously completes hundreds to thousands of charge-discharge cycles in a high temperature environment, monitors the capacity attenuation rate and internal resistance growth of the battery, and evaluates the stability of long-term high temperature use; Third, the high temperature thermal stability test, which tests the thermal decomposition temperature and thermal runaway trigger threshold of the battery by gradually increasing the temperature, and evaluates the safety risk in a high temperature environment; Fourth, the high temperature rate performance test, which carries out charge-discharge tests at different rates in a high temperature environment, and evaluates the performance under high current charge-discharge. The standard requirements for high temperature performance test of mainstream commercial sodium batteries are that the capacity retention rate is not less than 80% after 3000 cycles at 45℃, and the thermal decomposition temperature is not less than 300℃, to ensure stable use in high temperature outdoor, machine room, tropical areas and other scenarios.