How to Charge a LiPo Battery for the First Time?

Last Updated on December 10, 2023 by Jaxon Mike

Lithium polymer (LiPo) batteries are a type of rechargeable battery that has become very popular in recent years. As the name suggests, LiPo batteries use a polymer electrolyte instead of the more traditional liquid electrolyte.

This allows the battery to be lighter and experience less leakage than older battery technologies.

LiPo batteries are most commonly found in high-drain devices like drones, RC vehicles, vaping devices, and other small electronics.

Their light weight and ability to deliver short bursts of high current make them well-suited for these applications. However, they require special care and handling compared to other rechargeable batteries.

Why Proper Charging is Important for LiPo Batteries?

Charging a LiPo battery properly is extremely important for safety and maximizing battery life. LiPo batteries are fundamentally unstable at overcharge and may catch fire or explode if mishandled. It’s critical to use the right type of LiPo charger and adhere to the manufacturer’s charging guidelines.

Additionally, the first charge sets the stage for the battery’s capacity and lifecycle. Improper initial charging can greatly diminish performance down the road. That’s why extra care should be taken when charging any LiPo for the first time.

Choosing the Right LiPo Charger

The cardinal rule is to only use a charger specifically designed for LiPo batteries. Chargers meant for NiMH or lead acid batteries can overcharge a LiPo past its safe voltage threshold. At best this will severely shorten the battery’s lifespan. At worst, it can cause a catastrophic failure.

LiPo chargers have precise voltage limits for each cell and will shut off when the target charge is reached. This prevents overcharging. They also have a balanced charging function that brings each cell in a multi-cell pack to the same level of charge. Imbalances between cells can also lead to premature battery failure.

The most common types of genuine LiPo chargers include:

• Simple Balance Chargers: These only balance charge batteries and do not have other functions. They are the most affordable LiPo charger but are slow and lack features.
• Advanced Computerized Chargers: These high-end smart chargers offer a full suite of charge options and data readouts. They’re the fastest and most full-featured but are expensive. Popular models are made by Traxxas, Venom, and Hitec.
• Multi-Chemistry Chargers: As the name implies, these can charge many different battery chemistries making them versatile. However, their LiPo balance charging is not as advanced as dedicated units.

If on a tight budget, simple balance chargers are suitable for charging 1-2 LiPo packs as a beginner. Computerized chargers are worthwhile for enthusiasts charging multiple packs regularly.

General Safety Precautions When Charging LiPo Batteries

Take these safety steps whenever charging LiPo batteries:

• Never leave batteries unattended during charging. Remain observant of the pack for any signs of swelling or overheating which can precede fire. Disconnect immediately if there are any issues.
• Charge in a fireproof container or bag. This safely contains any flare up should the pack go into thermal runaway. LiPo safe bags are inexpensive.
• Keep an ABC fire extinguisher nearby. Class D extinguishers designed for lithium/metal fires are ideal but more expensive. ABC extinguishers can still be effective. Having an extinguisher close by is a prudent safety step.
• Charge away from flammable materials. Keep batteries away from paper, plastic, carpet, wood, etc. A concrete garage floor or metal workbench are safer locations.
• Inspect packs before charging. Look for any loose shrink wrap, swollen cells, damage, or exposed wires. Do not attempt to charge questionable packs. Properly dispose of them instead.
• Do not exceed the charger’s recommended load. Most LiPo chargers have a maximum charge current of 5A or less. Drawing more can potentially overheat the unit.

Getting Started With Your First LiPo Pack

Once you’ve selected an appropriate LiPo battery charger for your needs, follow these steps to safely charge a new LiPo pack for the first time:

Examine the Pack

Closely look over the battery for any damage or manufacturing defects. All cells within the pack should be flat, not puffy or swollen. The plastic shrink wrap around the pack should be free of tears and fully intact. There should be no exposed internal wiring.

Also check that the discharge connector is securely soldered without broken leads or corrosion. The balance connector must be firmly attached as well.

Do not attempt to charge any pack with physical defects. It could be unsafe.

Determine the Pack Configuration

LiPo packs come in various cell counts, voltages, and capacities. The cell count and voltage will be clearly listed on the pack such as “3S/11.1V” for a 3-cell, 11.1 volt pack or “4S/14.8V” for a 4-cell, 14.8 volt one.

The capacity rating (mAh or milliamp-hours) indicates how much stored energy it holds. Higher mAh numbers equate to more running time. Capacities for LiPo packs commonly range from 500mAh to over 5000mAh.

Make sure you know your pack’s specifications. This ensures the charger settings will match.

Set the Charger Accordingly

With a simple balance charger, manually set the channel switch to match the pack’s cell count. On a computerized charger, enter the number of cells into the user interface.

Then set the proper charging current (amps). A good rule of thumb is to charge at 1C (one times the capacity). So a 1000 mAh battery would be charged at 1 amp, a 5000 mAh at 5 amps, etc.

It’s also wise to configure the charger to automatically stop when the battery reaches no higher than 4.2 volts per cell (4.2V for 1S, 8.4V for 2S, 12.6V for 3S etc). This prevents overcharging.

Consult your charger’s instructions for exactly how to dial in these parameters. Settings differ between models.

Connect the Battery

With the charger powered off, go ahead and connect the discharge lead to the charger output port. Ensuring the balance lead is securely mated as well. Get all connections firmly seated.

Begin Charging

Power on the charger and it will begin the constant current/constant voltage charging cycle, balancing the cells along the way. The charging light will indicate status.

Monitor the pack closely and watch for the light to change once fully charged. Disconnect the battery promptly.

Disconnect the Battery and Inspect

When charging is complete, power off the charger and carefully disconnect the LiPo. Handle by the connector, not the battery pouch.

Inspect that the pack is cool to the touch and shows no signs of puffiness or swelling. This indicates a safe charge.

Also examine the balance connector. The plastic around each pin should be evenly melted and flat. Any pin mounded or shaped differently suggests that cell was overcharged. Discontinue use of such packs.

Cell Voltage Check

As an extra precaution after the first charge, you can spot check the individual cell voltages with a LiPo cell voltage checker. These handy devices plug into the balance lead and display each cell’s voltage.

All cells should be within a close range of each other at around 4.2V per cell. Any high or low readings can again hint at an imbalance or improper charging.

Storage and Disposal

When not in use, LiPo batteries should be discharged to around 3.8V per cell for storage. This is about 60% charge level. Storing fully charged or depleted packs hastens deterioration.

Wrapping packs in plastic bags or taping the connector contacts also prevents short circuits during storage.

Old LiPo packs that have reached the end of their useful life must be disposed of properly. They contain hazardous materials so should never be thrown in household trash. Instead take them to a battery recycling center or hazardous waste collection site.

Charge Additional Packs

The first charge is always the most crucial. Once you have a feel for properly charging your initial LiPo pack, repeating the process is straightforward for additional packs.

You now know how to safely set up and operate your LiPo charger, identify pack specs, monitor the charge process, and handle charged batteries. Just apply the same procedure for charging any new LiPo batteries in the future.

With some practice charging LiPos becomes second nature. Just always make safety the top priority. Charge batteries in the right charger with the right settings, under close supervision, and employ common sense precautions.

Finding More Tips and Advice

Learning to work with Lithium Polymer batteries does involve getting familiar with how to handle them safely. Fortunately, there are many web forums and videos with advice from the RC and drone communities, both of which use LiPos extensively.

Seeking out guides from reputable sources can provide lots of useful charging and usage tips. Owners clubs and manufacturer websites often have extensive LiPo battery documentation. Forums where enthusiasts discuss their own experiences are handy too.

With some research and prudent handling during charging, LiPo batteries can provide excellent performance and longevity. Just be sure to educate yourself and exercise due caution, especially when charging any particular LiPo pack for the first time. That initial charge sets the tone for maximizing battery life while staying safe.

So take it slow, follow the proper steps outlined here, and get those LiPos charged correctly right out of the gate. The satisfaction of safely using your new Lithium Polymer battery will make the effort worthwhile.

FAQs About the Initial Charging of LiPo Batteries

How long does it take to fully charge a LiPo battery?

Charge times vary based on charger power, charging current, and battery capacity. As an estimate, a 5000 mAh battery charged at 5A would take about 60-90 minutes. Smaller batteries may only take 15-30 minutes. Larger packs can take a few hours to fully charge from empty.

Can I charge multiple LiPo packs at once?

Yes, many advanced chargers have multiple independent charging channels to charge more than one pack simultaneously. However, never charge more packs than a charger is designed for and watch batteries closely for any issues.

Is it okay to occasionally leave a LiPo pack partially charged or discharged?

Leaving a LiPo fully discharged or fully charged causes more wear than maintaining around 60% charge (3.8V per cell). But the occasional full cycle won’t harm the battery. Just don’t make a habit of it for the best longevity.

Do I need a special power supply for my LiPo charger?

LiPo chargers often work with standard 12V DC power adapters. However, larger computerized chargers may require a higher voltage DC supply rated to deliver adequate power for the charger’s rating. Check your charger’s requirements.

How can I tell when a LiPo pack needs replacing?

Packs that get warm quickly, deliver reduced run time or show puffiness/swelling are nearing end of life. After around 500 charge cycles, most LiPo packs exhibit noticeable performance degradation.

Conclusion

Charging Lithium Polymer batteries for the first time does require getting educated on how to do so safely and effectively. This prevents battery damage while also avoiding accidents from mishandling.

While no battery is fully foolproof, taking prudent precautions goes a long way to maximizing LiPo performance and lifespan.

The essential steps covered in this guide provide a roadmap of proper charger selection, configuration, charging supervision, storage, and disposal.

Following these best practices during that critical first charge primes any LiPo battery pack for success down the road. And understanding correct LiPo usage empowers hobbyists to tap into the benefits of this popular battery technology.

So don’t be intimidated by warnings about the volatility of LiPo batteries. With responsible handling and charging, they are safe to use and provide outstanding power delivery.

Just make sure to follow the protocols detailed here whenever charging a LiPo battery for the first time.