1. Risk of overcharging
Shortened battery life: When lithium batteries are overcharged, the chemical structure of the battery will be damaged, resulting in reduced capacity and shortened cycle life.
Safety hazards: Overcharging may cause the internal temperature of the battery to rise, decompose the electrolyte, and produce gas, increasing the risk of explosion and fire. This situation is particularly significant in high-energy-density batteries.
2. System design and size adjustment
Proper system sizing: When designing a solar-wind hybrid system, the first considerations are the maximum charge and discharge currents the system can handle, as well as the total energy transfer. This includes choosing the right charge controller and inverter.
Case: A farm that installed solar panels and wind turbines did not adjust the system correctly in the early stages, causing the lithium battery pack to be overcharged in continuous sunny and windy weather, causing early degradation of the battery pack.
3. Charging configuration and management
Correct charging settings: Ensure that the charging parameters of each battery cell and the entire battery pack are set correctly, including charging voltage and cut-off current.
Case: A smart home system uses lithium batteries as backup power sources, and the charging parameters are accurately configured through software to avoid overcharging and extend battery life.
4. The importance of battery management system (BMS)
Monitoring and protection: BMS is key to preventing overcharging. It monitors various parameters of the battery, such as voltage, current and temperature, and disconnects charge or load when an abnormality is detected.
Case: An electric vehicle is equipped with an advanced BMS. During a long charging process, the BMS successfully prevented overcharging of the battery and avoided potential safety accidents.
5. Economic and lifespan considerations
Long-term cost efficiency: Despite higher upfront costs, lithium batteries can be more economical in the long run due to extended lifespan and improved efficiency.
Configuration and upkeep: Proper setup and maintenance are crucial for safe lithium battery operation. Professional assistance is advised for complex setups.
Case study: A commercial building invested heavily in a solar-lithium battery system. Professional configuration and maintenance led to surpassing battery life expectations, significantly enhancing cost-effectiveness over lead-acid systems.
6. Conclusion
When using lithium batteries in hybrid solar-wind systems, preventing overcharging is key to maintaining battery performance and safety. By employing meticulous system design, accurate charging setups, and efficient BMS, battery lifespan and system safety can see substantial enhancements. Engaging in professional system design and upkeep safeguards costly battery investments and secures the system’s long-term reliability and economic viability.
Learn More：Solar–wind hybrid renewable energy system: A review – ScienceDirect
