The core of a residential solar-energy storage system consists of photovoltaics, batteries, and an energy storage inverter. Residential energy storage is combined with residential photovoltaics to form a residential solar-energy storage system, which mainly includes multiple components such as battery cells, energy storage inverters (bidirectional converters), and module systems.
Residential energy storage system products generally include two types: integrated units (residential photovoltaic energy storage inverter integrated units) and split units (inverter + battery system).
Integrated Unit: A home-use photovoltaic energy storage inverter integrated unit is an integrated system that houses the photovoltaic inverter, battery, and controller. It features a convenient and intuitive touchscreen display showing the operating status, parameter modification, and multiple operating modes for ease of use. Generally, it offers three operating modes: solar priority mode, AC (mains) priority mode, and SE priority mode (peak-shifting power mode).
Split-type (inverter + battery system): In residential split-type systems, the battery and inverter are installed separately. Users match a residential energy storage inverter according to their needs. Additionally, a switching power supply or inverter can be used as a backup power source. Generally, there are four types: hybrid residential PV + energy storage systems, coupled residential PV + energy storage systems, off-grid residential PV + energy storage systems, and PV energy storage management systems.
The mainstream technology for residential energy storage is lithium iron phosphate, while sodium ion and lithium manganese iron phosphate are emerging paths for the future.
Currently, energy storage battery technologies include lithium-ion, lead-acid, and flow batteries. Lithium iron phosphate batteries, due to their high safety and long cycle life, are more in line with the design requirements of energy storage batteries than ternary lithium batteries, and are the mainstream development route for energy storage batteries. Tesla's energy storage batteries are also gradually shifting from the ternary route to the lithium iron phosphate route.
