AC-coupled and DC-coupled batteries are two different approaches to integrating battery storage into a solar energy system.
The main difference lies in how the batteries are connected to the system.
AC Coupled Batteries
AC-coupled batteries are connected to the alternating current (AC) side of the system. This means that the energy generated by the solar panels is first converted to AC power and then sent to the grid or used to charge the batteries. AC-coupled systems typically use an additional inverter to convert the DC power from the solar panels to AC power for use in the home or to charge the batteries. This setup allows for more flexibility in terms of battery selection, as any AC-compatible battery can be used.
DC Coupled Batteries
On the other hand, DC-coupled batteries are connected to the direct current (DC) side of the system. In this configuration, the energy generated by the solar panels is directly sent to the batteries for storage without the need for an additional inverter. The DC power from the solar panels is used to charge the batteries, and the excess energy can be converted to AC power for use in the home or sent to the grid. DC-coupled systems are often more efficient because there are fewer conversion losses since the energy does not need to be converted from DC to AC and vice versa.
In summary, the main difference between AC-coupled and DC-coupled batteries is the point at which the batteries are connected in the system. AC-coupled systems have the batteries connected on the AC side, while DC-coupled systems have them connected on the DC side. The choice between the two depends on factors such as system design, efficiency, and battery compatibility.