Let’s know something about LiFePO4 Batteries In Series & Parallel With

Lithium Iron Phosphate (LiFePO4) batteries have gained popularity due to their high energy density, long cycle life, and safety features. When using LiFePO4 batteries in series and parallel configurations, it is important to consider the advantages and disadvantages of each setup. Let's briefly understand the series and parallel connection of lithium iron phosphate batteries in order to find the connection that meets our own needs.

Series Connection

1. Definition

Series connection of LiFePO4 batteries involves sequentially connecting the batteries one by one, from the positive terminal of one battery to the negative terminal of the next.

The characteristic of the series connection is that the current remains the same while the voltage increases. For example, two 12V 200Ah batteries in series, the current is 200A and the voltage is 12V×3=36V.

2. Pros

• Increased Voltage:Connecting batteries in series increases the overall voltage, which can be beneficial for applications requiring higher voltage levels.
• Enhanced Efficiency:Each battery evenly shares the load, ensuring that each battery charges and discharges at the same rate. Series connections allow for a more efficient use of battery capacity. The increased voltage helps reduce resistive losses during discharge, resulting in improved overall system efficiency.

3. Cons

• Capacity reduction:In series, the total capacity is the same as the capacity of a single battery. Therefore, connecting batteries in series does not increase the overall capacity of the battery pack.
• Balancing Issues:It is important to ensure that the batteries in series are well-balanced to prevent overcharging or discharging of individual cells.
• System vulnerability:If one battery in series fails, it may cause the entire system to malfunction.

Parallel Connection

1. Definition

The parallel connection of LiFePO4 batteries refers to connecting the positive terminal to the positive terminal and the negative terminal to the negative terminal of several batteries.

The characteristic of the parallel connection is that the voltage remains the same while the current increases. For example, two 12V 200Ah batteries in parallel, the current is 200A×3=600A and the voltage is 12V.

Pros

• Increased Capacity:Parallel connections combine the capacities of multiple LiFePO4 batteries, resulting in higher overall capacity. This is beneficial in applications that demand longer runtimes or higher energy storage capacity.
• Improved Cell Balancing:Parallel connections help equalize the charge/discharge characteristics among individual cells. If one cell has slightly lower performance, it can benefit from the higher currents provided by other cells, thereby improving overall battery pack performance.
• Redundancy:Parallel connection provides redundancy, so if one battery fails, the others can continue to supply power.

Cons

• Increased Complexity:Parallel connections require more interconnections and monitoring to ensure proper balancing of charge and discharge currents. This complexity can lead to higher installation and maintenance costs.
• Cell Mismatch:In parallel configurations, differences in cell capacity, age, or internal resistance can lead to cell mismatch issues, affecting the overall performance and longevity of the battery bank.
• Reduced Voltage:Parallel connections do not increase the voltage output of the battery pack. If higher voltages are required for specific applications, series connections may be more suitable.
• The risk of overcharging and overheating increases:Parallel connection increases the overall capacity of the battery system, making it more likely to consume current that exceeds the battery's processing capacity, leading to overcharging, overheating, and even fire hazards.

Series-Parallel Connection

In a series-parallel connection, groups of batteries are connected in parallel to increase overall capacity, and then these groups are connected in series to increase voltage. The order should be parallel connection first and then series connection.

For example, sixteen 12V 100Ah batteries are divided into four groups in parallel, and then connected them in series. The total voltage is 12V×4=48V, the current is 100A×4=400A, and the capacity is 48V×400Ah=19200Wh.

Pros

• Increased Voltage and Capacity: By combining series and parallel connections, a series-parallel configuration allows for both higher voltage and increased capacity. This can be beneficial in applications that require both higher power and longer runtimes.
• Flexibility:Series-parallel connections offer flexibility in designing the battery system to meet specific voltage and capacity requirements. It allows for customization and optimization of the battery pack for different applications.

Cons

• Increased Complexity:Series-parallel connections introduce more complexity in wiring and management of the battery system. It requires careful planning and implementation to ensure proper balancing, charging, and discharging of individual cells or cell groups.
• Higher Risk of Imbalance:With more cells or cell groups connected, the risk of imbalance increases. Variations in cell performance, aging, or other factors can lead to unequal charging or discharging among cells, reducing overall capacity and efficiency.
• Safety Concerns:The risk of overvoltage or overcurrent conditions also increases with series-parallel connections. A failure or malfunction in one cell or cell group can impact the entire battery pack's safety. Adequate monitoring, protection circuitry, and safety measures are necessary to mitigate these risks.

How Many Acoucou Batteries Can You Connect In Parallel Or Series?

The number of batteries that can be connected in series is usually determined by the specifications of the battery manufacturer. For example, Acoucou allows up to four 12V lithium batteries to be connected in series, forming a 48 volt system. It is important to consult the battery manufacturer to ensure that your series connection remains within their recommended limits. If you need, you can contact us and we will give you the optimal solution.

Notice: Whether in series or parallel, uniformity is very essential. Different batteries with different brands, capacities and types are not recommended to use together.

LiFePO4 batteries offer numerous advantages for energy storage applications, and understanding the pros and cons of using them in series and parallel configurations is crucial for designing reliable and efficient battery systems. Whether choosing series or parallel connections, proper planning, monitoring, and maintenance are essential to maximize the performance and lifespan of LiFePO4 battery banks. Acoucou BMS helps you to monitor the batteries on the screen more conveniently.