How to Parallel Lifepo4 Lithium Batteries 

When diving into LiFePO4 battery charging, understanding the different types of battery connections is foundational. These connections determine how individual cells or packs share electrical current, impacting overall voltage, capacity, and charging dynamics. There are two primary connection configurations:

• Series Connection:In a series setup, cells are linked end-to-end, with the positive terminal of one connected to the negative terminal of the next. This elevates the total voltage to the sum of all the individual cells while the capacity remains consistent with a single cell. For LiFePO4 batteries, often with a nominal voltage of 3.2V, series connections are crucial for applications requiring higher voltage.
• Parallel Connection: In parallel configurations, cells are connected side by side, with all positive terminals and all negative terminals linked together. This approach augments the battery’s total capacity, summing up the capacities of all connected cells, while the voltage mirrors that of one cell. When more energy storage or prolonged discharge times are needed without an increase in voltage, parallel connections shine.

For advanced applications, like powering electric vehicles or extensive renewable energy systems, LiFePO4 batteries can be arranged in a combination of series and parallel, known as “series-parallel” configurations. This setup tailors the battery pack to meet specific voltage and capacity demands, ensuring optimal performance and longevity.

Remember not to mix batteries of different voltages. Using batteries with varied voltages can lead to uneven charging and discharging rates, which in turn can cause strain and imbalances among the cells.

If the battery gets out of balance, disconnect the batteries, charge them individually and reconnect them again. When charging in a series connection, multi-bank is the preferred choice.

When connecting the batteries in parallel, you should ensure the battery is within 100 millivolts (100mV or 0.1V); if not, there is an increased chance of battery balancing. So, before connecting the batteries, completely charge them individually and check with the voltmeter.

The charges to charge the battery must be of slightly higher voltage. Low voltage chargers will not affect the battery adversely but cannot provide full rated capacity. While BMS may disconnect the battery when having higher voltages than the above-given requirements.

For a successful parallel setup, it’s crucial that all four batteries possess the same voltage, capacity, state of charge, and ideally hail from the same manufacturing batch. This uniformity ensures an even distribution of charging and discharging duties across the batteries.

Can I Charge A LiFePO4 Battery With A Normal Charger?

The direct answer to your question is, YES!

A normal battery charger of would be enough to charge a lithium battery. Moreover, sometimes an AGM charger would also work fine for lithium batteries.

But here it is to be noted that battery chargers must be of slightly higher voltage. Following are some of the charging parameters you must remember:

There are other methods like, charging LiFePO4 batteries with a generator or solar panel will also work fine. But when charging LiFePO4 batteries with solar panels or generator you will typically need a suitable charger or a charge controller specifically designed for LiFePO4 batteries.