How to Balance Lipo that is out of Balance

Power Up Safely: How to Balance an Unbalanced Lipo Battery


Lithium polymer batteries, also known as lipo batteries, are rechargeable batteries that have become increasingly popular in recent years due to their high energy density and lightweight design. They are commonly used in a wide range of applications, including remote control cars, drones, and portable electronic devices such as smartphones and laptops. However, despite their many benefits, lipo batteries require careful handling and maintenance to ensure optimal performance and safety.

One essential aspect of maintaining a lipo battery is balancing it. Balancing a lipo battery involves ensuring that each cell within the battery is charged to the same voltage level.

This is important because if there is an imbalance between cells, some cells will be overcharged while others will be undercharged. Overcharging can cause the battery to swell or even catch fire, while undercharging can reduce the battery’s capacity and lifespan.

Occasionally, a lipo battery may become out of balance despite proper usage and maintenance. This could happen due to various reasons such as overuse or improper charging methods.

When a lipo battery becomes out of balance, it poses potential safety risks and can lead to reduced performance. Therefore it’s crucial to know how to identify an out-of-balance lipo battery and learn how to balance it correctly before using it again.

In this article, we will guide you through the process of balancing your lipo batteries properly while providing helpful tips on identifying when they’re out of balance. By following these steps carefully, you can ensure that your lipo batteries remain safe and perform at their best for longer-lasting use.

Understanding Lipo Battery Balance

What it means for a lipo battery to be in balance

To understand what it means for a lipo battery to be in balance, we must first understand some basics of lipo batteries. Lipo batteries are made up of several cells connected in series.

Each cell has a nominal voltage of 3.7 volts, and the total voltage of the battery is the sum of the individual cell voltages. For example, a 3S (three cells in series) lipo battery has a nominal voltage of 11.1 volts.

When we say that a lipo battery is “in balance,” we mean that each cell within the battery has the same voltage as all other cells. This is important because if one cell’s voltage is significantly higher or lower than its peers, it can cause problems such as reduced capacity and even fires.

The consequences of an unbalanced lipo battery

An unbalanced lipo battery can have several negative consequences, both in terms of performance and safety. Firstly, an unbalanced battery will have reduced capacity compared to a balanced one. This is because when one or more cells are at a significantly different voltage than their peers, they will discharge more quickly than others during use, leading to reduced runtime on a single charge.

Secondly, an unbalanced battery will have decreased lifespan compared to its balanced counterparts. When one cell discharges faster or charges slower than its peers due to being out-of-balance, it will begin to degrade faster than others over time and ultimately fail sooner than expected.

– and most importantly – an unbalanced lipo battery poses significant safety hazards due to potential thermal runaway caused by overcharging or over-discharging cells with different voltages within them. Thermal runaway occurs when one cell overheats due to being overcharged or discharged too quickly while its peers are still at a lower voltage.

This can lead to a fire or explosion, which can be dangerous and even deadly. It is essential to keep your lipo battery balanced for both performance and safety reasons.

Identifying an Out of Balance Lipo Battery

Uneven Cell Voltages

One of the most common signs that a lipo battery is out of balance is uneven cell voltages. Each cell in a lipo battery should have a similar voltage, but if one or more cells have a significantly higher or lower voltage than the others, it can indicate an imbalance. This can be checked using a battery checker or multimeter.

Simply connect the checker to each cell individually and compare the readings. If there is a significant difference between any of the readings, it’s likely that your lipo battery is out of balance.

Inconsistent Charging Times

Another sign that your lipo battery may be out of balance is inconsistent charging times. When a lipo battery is in balance, each cell charges at roughly the same rate and reaches full capacity at around the same time.

However, if one or more cells are significantly weaker than others, they may take longer to charge fully while other cells reach full capacity quickly. This will result in inconsistent charging times across different batteries and can indicate an imbalance.

Using a Voltage Checker or Multimeter to Confirm Imbalance

To confirm whether your lipo battery is truly out of balance, you can use either a voltage checker or multimeter to measure voltage levels for each individual cell. A voltage checker will typically display readings for individual cells on its screen when connected to your lipo battery’s balancing connector port.

If you don’t have access to a voltage checker with built-in balancer functionality, you can also use a multimeter by connecting its probes directly into each balancing lead on your balancing cable while it’s plugged into the charger (or with no load). Do this reading with caution though since there are high voltages involved.

By measuring individual cell voltages using these tools and comparing them with the manufacturer’s recommended voltage values, you can determine whether your lipo battery is out of balance or not. In case it is out of balance, you will want to perform a balancing procedure.

Other Signs of Lipo Battery Imbalance

Apart from the above two mentioned indicators, a few other signs that may indicate an imbalance in your lipo battery can be – Decreased performance and overall capacity

– Swelling or deformation on the battery casing – Unusual heat output or warm temperatures during charging.

Keep in mind that these signs may also indicate other issues rather than just an imbalance. Always use caution when handling lipo batteries and be sure to take appropriate safety measures before attempting to balance them.

The Importance of Identifying Lipo Battery Imbalance

Identifying whether your lipo battery is out of balance or not is crucial for safe and efficient operation. An imbalanced lipo battery poses a greater risk as it has weakened cells that could be overcharged or discharged too much which may lead to overheating, venting gases, swelling, leaking electrolyte and even fire hazards. So always keep an eye on any signs mentioned above and never leave your charging batteries unattended.

Balancing Techniques

As mentioned earlier, there are two methods for balancing a lipo battery that is out of balance: passive and active balancing. Both of these techniques have their pros and cons, so it’s important to understand the differences between them before deciding which one to use.

Passive Balancing

Passive balancing is a simple method that involves discharging the high cells in a lipo battery through resistors until they reach the same voltage as the low cells. This technique doesn’t require any specialized equipment but can take quite a bit of time, especially if the imbalance is severe. To perform passive balancing, you’ll need a voltage checker or multimeter to monitor each cell’s voltage level.

Once you’ve identified the high cells, connect them to resistors with an appropriate resistance rating. The resistance rating should be calculated based on the difference in voltage between high and low cells.

The more significant the difference, the higher resistance required. After connecting resistors to high cells, plug in each resistor into any device that can discharge electricity at its rated power (such as light bulbs).

Leave it this way until all cell voltages are nearly matched. Check frequently because sometimes cells may match quickly while others might take longer.

Active Balancing

Active balancing uses specialized chargers or balancers specifically designed for lipo batteries that can balance each cell individually during charging or discharging. It’s faster than passive balancing but requires an additional investment in equipment. To perform active balancing using a charger or balancer, first connect your battery to it based on its specific instructions.

Select your preferred charging rate and wait for the charger/balancer to finish its work. The charger/balancer will continuously monitor each cell’s voltage levels and adjust its output accordingly until all cells reach equal voltages within safe limits.

Some chargers/balancers offer more advanced features like cycle charges or storage settings. These options help prolong battery life and reduce the risk of future imbalances.

Which Balancing Technique is Right for You?

In general, passive balancing is suitable for those with a tight budget or who aren’t in a hurry to get their battery back into balance. This technique can take several hours or even days depending on the severity of the imbalance, so it’s not ideal if you need your battery right away.

Active balancing, on the other hand, is faster and more precise but requires an initial investment in specialized equipment. This method is ideal for those who frequently use lipo batteries and want to prolong their lifespan.

Ultimately, the choice between passive and active balancing depends on your personal preference, budget, and time constraints. Regardless of which method you choose, always ensure that you follow safe handling procedures when dealing with lipo batteries to avoid any safety hazards.

Section V: Preventing Future Imbalances

Understanding the Causes of Imbalances

Before you can effectively prevent future imbalances, it’s important to understand what causes them in the first place. In most cases, imbalances occur due to overcharging or over-discharging one or more cells in the battery. This can be caused by a faulty charger, an unbalanced load on the battery, or simply by neglecting to monitor the battery’s charge levels during use.

Tips for Preventing Imbalances

1. Use a high-quality charger. One of the best ways to prevent battery imbalances is by using a high-quality charger that is designed specifically for lipo batteries.

Look for a charger that has built-in balancing functionality and that allows you to set specific charging parameters. 2. Monitor your battery closely during use.

If you’re using a lipo battery in an RC car or airplane, make sure to monitor its voltage levels closely during use. If you notice any signs of imbalance, such as uneven power output or slower than usual performance, take your vehicle out of commission until you can balance the battery again.

3. Avoid overcharging or over-discharging your battery. As mentioned earlier, one of the main causes of imbalanced lipo batteries is overcharging or over-discharging individual cells within the battery pack.

To avoid these issues, be sure to follow proper charging and discharging protocols at all times. 4.Take care when transporting and storing your batteries.While transporting and storing your batteries avoid keeping them in areas with extreme temperatures as this could cause damage leading to imbalance.


Balancing a lipo battery that is out of balance is crucial for safety purposes as well as ensuring optimal performance from your device powered by this type of battery technology. By understanding what causes imbalances and taking steps to prevent them, you can help extend the lifespan of your lipo batteries and keep them functioning at their best for years to come.

Remember to always use proper charging protocols, monitor your battery’s voltage levels closely during use, and take care when storing and transporting your batteries. By doing so, you’ll be able to enjoy the benefits of lipo battery technology with peace of mind knowing that you’re taking all necessary safety precautions.