RC (radio-controlled) cars are a popular hobby for both kids and adults alike. These miniature cars are powered by rechargeable battery packs that allow them to zip around at high speeds. Having a properly charged battery is crucial for maximizing runtime and performance of your RC car. In this guide, I will provide a step-by-step guide on how to safely and effectively charge an RC car battery. I will cover the materials needed, the proper charging steps, battery maintenance tips, safety precautions, and more. Whether you’re new to the hobby or a seasoned RC enthusiast, you’ll learn the ins and outs of charging your car’s battery pack to keep it running at peak condition.
What is An RC Car?
A radio-controlled (RC) car is a miniature car that is guided by a radio-controlled handheld transmitter. The transmitter communicates with a receiver inside the car that controls the steering and throttle. RC cars come in many varieties including on-road cars meant for paved surfaces, off-road trucks designed for rough terrain, and even high-performance models that can reach speeds over 100 mph. These battery-powered cars use rechargeable packs that power an electric motor and allow the cars to run for extended periods. RC cars range from inexpensive toy-grade models to highly sophisticated hobby-grade cars used for racing. They provide an enjoyable hobby for all ages and allow you to get a feeling of driving without actually being behind the wheel.
The Importance of RC Car Batteries
A properly charged battery is absolutely crucial to the performance of any RC car. The rechargeable battery pack provides all the power that drives the electric motor and electronics in the car. When the battery charge runs low, the car will start to lose speed and power. Eventually the battery must be recharged in order for the car to operate again. An insufficiently charged battery can lead to sporadic operation or unexpectedly short runtimes.
Many factors affect battery life including motor output, terrain driven on, payload weight, driving style, and battery chemistry. Repeatedly running the battery down completely can also shorten its overall lifespan. That’s why it’s important to have a properly charged battery before each use, and to monitor voltage levels during runs. Proper storage and maintenance of the battery pack between uses also helps maximize performance and lifetime. So having the knowledge to safely and effectively charge your RC car battery is one of the most valuable skills you can have to enhance your RC experience.
List of the Best LiPo Batteries for RC Cars
Materials Needed To Charge An RC Car Battery
1. Chargers
The most essential item required to charge your RC car battery is a compatible battery charger. You should select a charger that is designed specifically for the type and voltage of battery used in your car. Most RC cars use lithium polymer (LiPo) batteries which require LiPo-compatible chargers. The charger must match the number of battery cells in the pack, with higher voltage packs needing chargers with multiple outputs.RC car chargers come in two main varieties – simple wall plug-in chargers and more advanced multi-chemistry chargers. Simple chargers just need to be plugged into an AC outlet and connected to the battery to begin charging.
Advanced chargers allow you to configure and monitor the charge process in more detail. Look for a charger with features like charge rate selection, cell balancing, discharge capability, and charge data displays. Advanced chargers provide more control and information, but simple chargers can also effectively charge a battery if used properly. Select a charger from a reputable hobby brand that is the proper type and rating for your particular battery. This will ensure safe, efficient charging cycles.
2. Battery packs
The rechargeable battery pack is the power source for your RC car. Lithium polymer packs come in a standard stick or brick configuration. Each pack will be rated with a cell count, voltage, and milliamp-hour (mAh) or capacity rating. Common RC car packs may have 2-4 cells with voltages ranging from 7.4V to 14.8V. Higher voltage packs deliver more power. The mAh indicates how much charge the battery can hold. Higher mAh cells can run longer but may impact speed.
Choose a pack that balances voltage and capacity for your car’s electronics and desired performance. Inspect battery condition before charging and don’t attempt to charge swollen or damaged packs. Only use a battery that precisely matches the specifications your RC car requires for proper and safe operation.
3. Connecting wires
To connect your charger to the RC car battery pack, you will need a compatible charging wire or harness. These typically have a standard charging connector on one end that plugs into the charger output. The other end will have a connector like a Tamiya, EC3, XT30, or others that match the charging port on your battery. Having a dedicated charging harness helps protect the delicate battery balance wires that connect each cell. The wires should be thick enough gauge to handle the charging current without overheating.
12 or 14 gauge silicone wire is commonly used. Ensure the connectors securely plug into both the charger and battery port to avoid issues with loose connections during charging. Using the proper connecting harness tailored for your charger and battery is essential for safe charging.
Proper Charging Steps
1. Checking battery voltage
The first step in charging your RC car battery is to check the current voltage of the battery pack. This helps determine the state of charge and whether the pack needs charging. Using a voltmeter, multimeter, or the voltage readout on advanced chargers, check the voltage of the battery. A fully charged LiPo cell has a voltage around 4.2V. Multiply this by the number of cells to determine the fully charged voltage of the pack.
For example, a fully charged 3S LiPo battery will read about 12.6V. If the voltage is significantly lower than the expected fully charged voltage, then the battery needs to be recharged. Most RC users try to recharge the battery when it drops to around 3.7-3.9V per cell, or about 11.1-11.7V on a 3S pack. Checking the voltage ensures the battery actually requires charging and allows you to monitor the charging process.
2. Connecting charger and battery
Once you’ve verified your battery needs charging, the next step is to make the physical connections between the charger and battery. Consult the manuals for your specific charger and battery to ensure proper connection. Generally, you’ll connect the charging harness to the output on the charger, ensuring a firm, secure connection. Then connect the battery side of the harness to the charging port on the battery, pressing firmly together. Inspect the connections to be sure they are tightly mated with no gaps.
Faulty connections can interrupt the charging process. Ensure polarity matches on the connections. Reversing the connectors can severely damage the battery and charger. With the physical connections double checked, you can now plug the charger into its AC power source to begin charging.
3. Setting charger parameters
If using an advanced programmable charger, there will be settings that need to be entered before starting the charge process. Based on the specifications of your battery, you will input the battery type (LiPo, NiMH etc.), number of cells in the pack, and the charge rate in amps or milliamps. These parameters provide the critical information the charger needs to deliver the proper amount of current tailored for the specific battery being charged. If the charger has auto-detect functions you may only need to confirm the detected settings are correct.
Chargers will often default to a standard 1C charge rate which is a safe level for most batteries. For faster charging you can increase the rate just make sure it stays within the battery’s recommended levels. Taking the time to properly set and check these charger parameters helps ensure an effective charge cycle.
4. Monitoring the charge
As the battery charges, you will want to monitor the process to ensure everything is going smoothly and to watch for any warning signs. More advanced chargers will show data like charging current, voltage, and time elapsed on a display screen. Even with simple chargers you should periodically check the temperature of the battery pack by touching it to feel if it’s getting excessively hot. The battery will heat up somewhat during charging but excessive heat can indicate a problem.
The battery should also be monitored for any swelling or bloating which requires stopping the charge right away. Observe the LED indicators on the charger for the status of charging. Most will show a red light during charging that turns green when charging is complete. Watching the charger and battery will help make sure optimal, safe charging without any errors.
5. Charge completion
Once the charger shows the battery is fully charged, you can disconnect the pack. Make sure to unplug the charger from the AC outlet first for safety. Carefully disconnect the battery from the harness, keeping wiring organized. An advanced charger screen may show the voltage reached a maximum of about 4.2V per cell, or 12.6V on a 3S pack, indicating a full charge. Check this voltage yourself with a meter if desired.
The battery may be slightly warm but should not be hot. Now the pack is ready to be installed into the RC car for maximum power and run time. Some advise letting the battery rest briefly before heavy use to allow cells to balance. Proper charging is complete and the battery is primed for your next RC adventure. Be sure to properly store and maintain the battery between uses.
Battery Maintenance Tips
1. Avoid overcharging/over-discharging
Properly maintaining your RC car battery is crucial to maximizing its performance and lifetime. First and foremost, you’ll want to avoid overcharging or over-discharging the battery. Overcharging occurs when the battery is continued to be charged after reaching full capacity. This can happen if the charging process isn’t closely monitored and stopped at the proper time. Overcharging can result in battery overheating, swelling, leaking, and eventually failure.
Similarly, you don’t want to over-discharge the battery by running it down past the recommended low voltage cutoff point for the battery type. This strains the battery and reduces its overall lifespan. Instead, you should charge the pack before it falls below about 3.7-3.9V per cell or as recommended. Carefully monitoring the charging and discharging process helps prevent operating outside safe voltage limits.
2. Store at proper temperature
Additionally, be sure to store your batteries at proper temperatures when not in use. RC car batteries should be kept in a dry location with temperatures between around 60-80°F to preserve battery life. Storing batteries outside of the ideal temperature range, especially in extreme hot or cold conditions, will cause more rapid deterioration. If you live in a climate with temperature extremes, try to keep the batteries in a controlled environment as much as possible.
For instance, avoid leaving battery packs in a hot garage or shed during sweltering summer months. Watch for any bulging of the battery case which can indicate damage from improper storage conditions. Maintaining batteries at the proper storage temperature will help batteries hold a charge when it’s time for your next RC adventure.
3. Regular charge/discharge cycles
Performing regular charge and discharge cycles can also keep your batteries in top shape. Depending on how often you use your RC car, plan to do a full charge and discharge of the battery every 1-2 months during long periods of inactivity. This cycling maintains the batteries and prevents deterioration from lack of use. Don’t allow batteries to sit unused for many months without periodic cycling.
Before longer term storage, it helps to charge the battery to about half capacity instead of fully charged or fully discharged. Then every month or two, do a full cycle bringing it to full charge and then safely discharging it. Regular exercise keeps those electrons flowing smoothly!
Safety Precautions
1. Use correct charger
When it comes time to charge your RC car batteries, be sure to follow proper safety precautions. First, only use the recommended charger for the particular battery type and specifications. Chargers are designed for specific battery chemistries and cell configurations. Using an incompatible charger can result in improper charging leading to battery damage or even fire in extreme cases. The charger must match the battery’s cell count, voltage, and charging levels. Don’t attempt to charge the battery by any other means than with the appropriate charger. Using the right charger for your battery is a basic safety measure we all must follow, without exceptions!
2. Monitor charging
You’ll also want to closely monitor the battery and charging process from start to finish. We’ve touched on this before, but cannot stress enough the importance of paying attention during charging. Watch for any concerning signs like excessive heat, odd odors, changed appearance or swelling of the battery case. Monitoring will ensure charging stops immediately if any problem arises, before damage occurs.
Follow the manufacturer’s guidelines for charging duration and use a timer to avoid overcharging. Observe charger lights and displays for charge status and any error indicators. While properly powered off after charging, double check the battery voltage and cell balance as a precaution. Diligent monitoring is essential every time you charge to prevent safety mishaps.
3. Avoid short circuit
Of course, you’ll want to avoid short circuits when handling RC batteries as shorts can spark fires. Securely cover any exposed battery contacts when not in use. Don’t allow battery connectors or wiring to contact metal surfaces which can cause dangerous shorts. Inspect wiring for damage before connecting. When installing the battery in your car, pay attention to polarity and ensure you don’t accidentally reverse the battery leads. Use electrical tape on any exposed wiring in the car. Also transport and store batteries in a non-conductive lipo safety bag. Being mindful to avoid accidental shorts keeps your batteries operating safely.
Frequently Asked Questions on How To Charge an RC Car Battery
1. What type of battery does my RC car use?
Most RC cars today use lithium polymer (LiPo) batteries. These are high performance rechargeable batteries that provide the power and run times needed for RC vehicles. LiPo batteries come in 2-4 cell packs ranging from 7.4V to 14.8V. They require specialized LiPo battery chargers. Double check your car’s manual to confirm the exact battery type and voltage required.
2. How can I tell when the battery needs recharging?
When your RC car starts slowing down and lacks power, it’s a sign the battery is running low and needs recharging. Check the battery voltage – fully charged LiPo cells are around 4.2V per cell. The battery should be recharged when it drops to 3.7-3.9V per cell or lower. For a 2 cell (2S) pack that’s 7.4-7.8V. Time how long your car runs to learn discharge times.
3. What type of charger do I need?
You need a charger designed specifically for the type of battery in your RC car. For LiPo batteries, you must use a LiPo-compatible charger. The charger should match the battery’s cell count and rated maximum voltage. There are simple chargers with basic functions and “smart” chargers with more advanced features and data displays. Read reviews to select a suitable quality charger from a reputable RC brand.
4. How do I connect the battery to the charger?
Consult the manuals for proper connection instructions. Typically a charging harness plugs into the charger on one end, and into the battery’s charging port on the other end. Make sure connectors are fully seated. Double check polarity. Monitor charging to ensure a proper connection.
5. How should I set the charger?
Most chargers will need to be configured with settings like battery type (LiPo, NiMH etc.), cell count, and charging current/rate. Smart chargers allow setting precise parameters tailored for your battery. Check the battery specs and charger manual for guidance on appropriate settings. A standard charge rate is 1C (battery capacity in mAh).
6. How long does charging take?
Charging time depends on the battery capacity, charger output, and charging rate selected. For example, a 5000mAh battery charged at 2A will take about 2.5 hours for a full charge. Charging at higher rates speeds charging but requires monitoring battery temp. Consult charger and battery specs to determine expected charge times.
7. How can I monitor the charging process?
Watch the charger’s display panel and LED indicators for charging status. On smart chargers, monitor voltage, current, and time. Check battery temperature occasionally by touching the pack – it should be warm, not hot. Also inspect for any swelling of the battery case. Charging is complete when the charger indicates full charge.
8. What do I do when charging is finished?
First unplug the charger from AC power before disconnecting the battery. Remove the battery from the charger safely. Some recommend allowing the battery to rest 10-15 mins before heavy use to allow cells to balance. Confirm full voltage (4.2V/cell) with a voltmeter if desired. Your battery is now charged and ready for action!
9. How do I properly care for my batteries?
- Avoid overcharging/discharging
- Charge to proper voltages (4.2V full; 3.7-3.9V storage)
- Store batteries at room temperature
- Prevent short circuits
- Perform occasional charge/discharge cycles
- Check for damage and swelling
- Allow to cool after use before charging
10. Is there anything else I should know about battery safety?
- Use only compatible chargers and batteries
- Constantly monitor charging
- Charge on non-flammable surfaces
- Don’t charge unattended
- Store and transport batteries in lipo safety bags
- Dispose of damaged batteries properly
- Take time to understand and follow manufacturer’s instructions
Final Thoughts
To wrap up, proper RC car battery maintenance and charging safety comes down to responsible handling. Be sure to use the right charger for your particular battery type and continually monitor the charging process. Don’t overcharge or over-discharge the batteries, and store them at ideal temperatures between uses. Additionally, perform occasional charge/discharge cycles during long periods of inactivity. Avoid short circuits by covering contacts, checking wiring, and attentive installation. If you treat your batteries with care and respect, they’ll deliver many hours of high-speed RC enjoyment. Just be diligent in watching for any troubling signs during charging and enjoy your RC hobby safely.
Enjoyed this guide of How To Charge An RC Car Battery? Then be sure to check out our other guides.