Solis Seminar 【Episode 63】: Essential Battery Tips for Home PV Energy Storage

Author：Solis Time：2024-10-23 09:15:00.0 Pageviews：123

Background

In the current market for household photovoltaic (PV) energy storage, the most common batteries are lithium-ion and lead-acid. When choosing a battery, users typically consider factors like cost, efficiency, and capacity. However, there are some often-overlooked parameters that also deserve attention.

Battery voltage range

Different inverters have different battery voltage ranges. If the voltage range doesn't match, the system might trigger an over-voltage or under-voltage alarm. For low-voltage batteries (48V systems), the rated battery voltage should be 48V or 51.2V, whether using lithium or lead-acid batteries. This is particularly important for lead-acid batteries, as incorrect voltage can easily cause an over-voltage alarm in the inverter.

For high-voltage batteries, it's crucial to ensure proper voltage matching between batteries and inverters. Most high-voltage batteries today are built by stacking cells in series. For example, a 5.12kWh battery has a rated voltage of 204.8V, while a 10.24kWh battery is rated at 409.6V. Once a battery capacity is chosen, make sure the rated voltage aligns with the inverter's voltage range to ensure compatibility.

Battery charging/discharging current

Low-power batteries can't handle high-power discharges, which means they can't effectively support backup loads. For example, colloidal, tubular, and lead-acid batteries are typically limited to supporting smaller loads.

As shown in the example:

If choosing a low-power or low-current battery, higher power demands will require more battery strings to be connected in parallel, for example：

Alternatively, user can use high-power or high-current batteries,

Additionally, if a customer chooses a battery that can handle 100A, but their inverter only supports 50A, the system will be limited to 50A. This mismatch results in lost battery performance. When using multiple battery groups in parallel, consider the total charging and discharging current. For example, if each battery supports 50A and three groups are used, the system might only support 100A instead of 150A, affecting overall power output.

Battery operating temperature range

When purchasing, ask the manufacturer about the full load operating temperature range. The general temperature range often just indicates the operating range. However, if the temperature reaches a certain point within this range, the battery might experience a current limit (power reduction). This could mean everything works fine in the summer, but power output drops in the winter.

Connection methods between battery modules

There are two ways to connect battery modules:

1)Traditional Wired Connection: During installation, connect power and communication cables between modules in sequence.

2)Cable-free Connection: These modules have a special structure. Once stacked, all power and communication cables connect automatically, significantly speeding up installation and improving connection stability.

0

All comments (0)：

+ More

Select Your Region

Solis Seminar 【Episode 63】: Essential Battery Tips for Home PV Energy Storage

Customer Hotline： +27 010 222 0181

Subscribe to our newsletter

Subscribe to our newsletter

South Africa