Batteries in Series vs .Parallel : Which is Better for You?

When you need more voltage or amps than a single battery provides and go shopping for batteries, terms like " Series and Parallel" can be confusing. To help you understand them better. We came up with this article.

The differences between Series wiring and Parallel wiring:

Series Wiring
· Wiring batteries in series increase the voltage.

Parallel Wiring
· Wiring batteries in parallel increases amp-hour capacity.

Let's take a brief study into Batteries Wiring. We’d start with Series wiring. This wiring method is the process of wiring batteries of similar voltage and amp-hour capacity together to increase the voltage to your needs. To do this. You wire the positive terminal unit(+) of the first battery to the second battery's negative end(-). For Instance, wiring 2 of our Bluetooth-enabled 12V 100Ah Lithium Iron Phosphate (LiFePO4) in series will output 24 volts with a capacity of 100 Ah. 
Note: The nominal capacity of the 2 batteries should be the same (small errors allowed).

Parallel wiring wires 2 or more batteries. You are improving the battery bank's amp-hour output while sustaining the battery's voltage level. The total volume of charge retained is capacity. To improve capacity. You wire the batteries' positive terminals(+) via a cable to the negative (-) via another cable until you reach the target.
Note: The voltage of the 2 batteries should be the same (error range 0.1V).

Want to know more? Deep in.

How Do I Wire Batteries In Series?

Ensure the batteries have the same voltage and capacity before wiring them in series. Mixing and matching your clothes is OK when you want to look your best on party night, but Mixing up batteries like clothes in your battery system is not a good idea. This process can be harmful, and your batteries might go bad.

 Here's A Step-By-Step Guide On Wiring Batteries In Series:

      • Connect the first battery's negative(-) wiring to the next battery positive(+) terminal.
      • Continue wiring batteries with this technique in a straight line (your "series").
      • Connect the positive(+) terminal of the first battery in the series to your application's positive(+) terminal.
      • Connect the negative(-) terminal on your application to the negative(-) terminal on the last battery in the series.

    What Are The Advantages of Wiring Batteries In Series?

        • Circuits in the series do not quickly overheat, making them useful near a potentially flammable source, such as dry plants or tissue.
        • The series circuits are simple to understand and build. It is easy to comprehend their basic nature, ensuring repairs are easy to carry out.
        • In a series circuit, the current must pass through all of the circuit's components. Resulting in all components carrying the same current.

    What Are The Disadvantages of Wiring Batteries In Series?

        • In a series-connected battery system, you can't acquire lower voltages from the battery bank without a converter.
        • When one point in a series circuit fails, the entire circuit will fail.
        • When the number of components in a circuit increases, the circuit's resistance grows.

    Can I Wire Batteries With Different Voltages In Series?

    It's never a bad idea to connect identical batteries in series. It will help if you avoid any condition where one battery is doing more work than the other. Use similar batteries in series and parallel at all times. In concept, you can wire batteries of different voltages in series as long as their capacity ratings are the same.

    However, other elements affect battery performance, like temperature, so come down from that wagon!

    Key Notes

        1. Never wire the batteries' unused positive(+) and negative(-) contacts. This action may cause a short circuit and harm the batteries and you.
        2. To avoid a short circuit and an explosion, use high-capacity cables for wiring.
        3. Observe the polarity of the batteries. Only then can wiring be done.
        4. The chemistry of the batteries used in a series wiring should always correspond to minimize explosion and harm, whether lead-acid or lithium-ion.
        5. Check your appliances' power and capacity requirements before installing a battery bank, as too much power or capacity might cause damage.

      How Do I Wire Batteries In Parallel?

      Mixing and matching without caution are not acceptable, as it is not allowed when wiring batteries in series. The voltage of the 2 batteries should be the same (error range 0.1V).

      Here's A Step-By-Step Guide On Wiring Batteries In Parallel:

          • Wire each battery's negative(-) point to the negative(-) terminal of the next.
          • Proceed with the positive(+) terminals in the same way.
          • Wire the last battery's positive (+) terminal to your application's positive(+) terminal.
          • Proceed with the negative(-) terminals in the same way.

      Keynotes

          1. By choosing batteries with a lower voltage and higher capacity, you can reduce the number of parallel cables.
          2. Both the lead-acid and lithium-ion batteries wired in parallel must be of the same type.
          3. Do not wire different types of batteries. Doing such may cause an explosion.
          4. When wiring batteries in parallel, match the capacities as close as possible to avoid one battery discharging faster than the other.
          5. Also, the age of the batteries should be the same; mixing old and new batteries would cause the old ones to drag the new ones down.

      What Are The Advantages of Parallel Wiring?

          • One of the most significant benefits of wiring batteries in parallel is: If one of the batteries fails, the other batteries can still sustain power.
          • You extend your system's possible runtime while keeping the voltage constant. 4 units of 12V100Ah Aolithium batteries in parallel can increase your runtime. 

      What Are The Disadvantages of Parallel Wiring?

          • The main disadvantage of wiring batteries in parallel instead of series is that the voltage level will be lower, which will result in a larger current draw. The higher the current, the thicker the wires, and the higher the voltage drop. Larger power appliances and generators are more difficult to use and less efficient when operating at lower voltages.
          • Parallel wiring needs a large number of wires.
          • Defect detection is more difficult in parallel wiring compared to series wiring.

        Can I Wire Batteries With Different Voltages In Parallel?

        Nope,  The higher-voltage battery will try to charge the lower-voltage battery to put the circuit back into balance. If you wire 4 different Aolithium batteries in parallel, the higher voltage battery distributes more voltage than the lower voltage batteries can handle.

        A voltage flood can take over if there is too much. The smaller battery overcharges, overheats, and catches fire or explodes because of this inequality and exposure to much electricity. For real, it's never a good idea for one battery to do more work than the other.

        Batteries In Series Vs. Parallel: Which Is For me?

        It depends on your needs. First, you need to clarify your electricity needs, how many electrical appliances you have, how much power and voltage the appliances are, and how much electricity you consume on an average day. Also, there is no better or worse option between series and parallel wirings. Both are important in the creation of battery systems. Parallel wirings have more challenges with charging and discharging processes. But learning how to harness the attributes of each one is necessary for a good solution. The needs of the applications you're trying to power with  (LiFePO4) Batteries will determine the strategy you implement.

        How Many Batteries Can I Wire In Series?

        The maximum number of batteries you can connect in series is usually determined by the battery and its manufacturer. For example, 12V100Ah-4s model allows up to 4 lithium batteries to be connected in series to produce a 48-volt system. Always double-check with your battery maker to be sure you're not going over their recommended battery series limit.

        How Many Batteries Can I Wire In Parallel?

        It is largely dependent on the manufacturers. Some batteries aren't restricted in any way. With Aolithium 12V 100Ah, you can wire up to  4 units in Parallel. The more batteries you connect in a parallel circuit, the more capacity and runtime you'll have. Keep in mind that the more parallel batteries you have, the longer the system will take to charge.

        There is also a significantly higher current with huge parallel battery banks. Effective system fusing is vital to avoid issues that can have disastrous implications with so much current available.

        Can batteries of different brands be connected in series or parallel?
        No, All brands of batteries are not supported to be connected with other brands of batteries because the batch of cells is not the same. Even if it is the same brand, connecting is not recommended if the purchase interval is more than four months.

        Is It Possible To Wire In Series and Parallel At The Same Time?

        You can connect groups of batteries in series and parallel to build a larger battery bank with a greater voltage. For example; 4 x 12V 100Ah Lithium Iron Phosphate (LiFePO4) batteries wired in series/parallel will give you  24V 400A. Note connect in Series first and then in Parallel



        Important Points to Remember while wiring batteries in series and parallel:

            • The voltage and capacity of a system wired in series will be increased.
            • Wiring batteries in series will boost voltage but not capacity.
            • Always use identical batteries when wiring them together.
            • If you're unsure, always consult a professional.

        Battery Charging In Series Vs. Parallel

        Batteries are wired in series and parallel charge the same way. Use a suitable voltage charger. 

            • Wire the positive(+) charger cable to the positive(+) terminal on the first battery in the series.
            • Wire the negative(-) charger cable to the negative(-) terminal on the last battery in the series for batteries wired in series.
            • Connect your charger in the same manner across a parallel bank for even charging: positive(+) to the first battery, negative(-) to the final battery.
            • An option is a multi-bank battery charger that can charge both series and parallel battery banks simultaneously. Always follow the manufacturer's instructions when it comes to charging your batteries.

        How We Can Help You

        Are you looking to learn more about Lithium Batteries and electrical systems? We understand how difficult it can be to build or upgrade an electrical system, so we're here to assist. Reach Our sales and customer service team at support@aolithium.com from 9 AM – 5 PM EST.

        You can also learn more about how Aolithium battery systems can power your lifestyle, discover how others have constructed theirs, and gain the confidence to get out there and stay out there by visiting our Facebook, Instagram, and YouTube pages.


        6 comments


        • Barry van Aswegen

          I would like to learn more about batteries for my inverter output power 300 / 500 watt with 2 12 volt batteries


        • Barry van Aswegen

          I would to learn more about batteries for my small inverter 12 volt DC to 220 volts AC output 300 / 500 watt 2 /12 volt


        • Barry van Aswegen

          I would like to learn more about batteries for my inverter output power 300 / 500 watt with 2 12 volt batteries


        • Sifiso Qwabe

          Good morning,I’m Sifiso Qwabe from Swaziland 🇸🇿,I would like to thank you so much for your experience…. you are the best and it’s very clear explanation.


        • Kenneth

          Im confused, is it really possible to connect positive to negative without short circuiting the battery


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