1) Battery Cells
Common chemical types: Lithium iron phosphate (LFP) is widely used due to its high safety, good thermal stability, and long lifespan; nickel-cobalt-manganese (ternary materials) has high capacity density but slightly higher cost. Different chemical types have different characteristics in terms of capacity, cycle life, and temperature adaptability.
Key indicators: Rated capacity (kWh), depth of discharge (DOD, generally recommended 80%-90% to extend lifespan), cycle life, charge/recovery efficiency, and operating temperature range.
2) Inverter and Control Unit
Power rating determines peak discharge capacity, and capacity rating determines the load size that can be supported. It needs to be matched with the characteristics of residential electricity consumption to ensure that critical loads are protected during power outages.
The control unit is responsible for SOC/SOH monitoring, charge/discharge strategies, and coordination with the photovoltaic system.
3) Monitoring and Thermal Management
The monitoring system can display capacity, health status, temperature, and power consumption curves in real time, facilitating daily maintenance and troubleshooting.
4) Safety and Compliance
Safety protection includes overcurrent, short circuit, temperature control, fire protection, and leakage protection. Compliance regulations involve local power grid connection requirements, building and fire protection codes, certification standards, etc.