What RC Battery Connectors Should I Use?

RC battery connectors, if you’re unfamiliar with radio control hobby electronics, are the female plugs attached to the wire leads of RC battery packs. The male plugs of devices needing the battery’s power input — such as radio receivers or electronic speed controls — receive the RC battery’s female plugs to form a connection that allows current to pass from the battery to the device. The same plug system is used to connect batteries to battery chargers for recharging.

For the purposes of this article, the term RC battery connectors will be used to mean both the plug and the wire lead or cable soldered onto it. RC battery connectors can be purchased with the lead already attached, but you can also buy the plugs and leads separately and do the soldering yourself if you have the tools and skills.

How manufacturers design and make their RC battery connectors can differ, but all of them have some characteristics in common. They’re usually brightly colored so they’re easily visible when installed in a crowded chassis or fuselage. RC battery connectors are also made sturdy enough so that you can repeatedly connect and disconnect them from devices or chargers without having to worry that they might break. Finally, RC battery connectors are meant to withstand the high voltages and electrical currents required by their intended applications.

Considering all of the features that they share, you might wonder why so many different types of RC battery connectors are available. The main reason is that different remote control model applications take different amounts of electrical power.

Hobbyists therefore need to have a choice of RC battery connectors that can withstand a variety of current ratings. Choosing the right connector is essential to enjoying optimal RC model performance and safety. Using the wrong RC battery connector, or a poor quality one, could lead to overheating and possibly even cause a fire.

The following information isn’t intended to be an encyclopedia of every RC battery connector ever made. But it will help you understand enough about RC battery connectors to know what to look for, and what questions to ask your hobby dealer, when you go shopping for them. It will also help you decide which types of RC battery connectors you might want to have handy as extras in your RC flight box or pit bag.

Having the right RC battery connectors is vital to the successful operation of any radio control model. Without them, you’d have no way of transferring the power stored in your battery pack to the electronic devices in your RC vehicle, RC boat, or RC aircraft. For everything to work properly, the female RC battery connectors attached to your battery packs must match with the male connectors on any motor, receiver, or electronic speed control to be powered by them. Here are some important factors to consider when selecting your RC battery connectors.

Compatibility

If you’ve just bought your first brand new, ready-to-run RC model and need to complete it by purchasing a battery separately, the obvious thing to do is get a battery that has the same connector type as whatever device it will power in your model. Check your model’s instruction manual and packaging. The manufacturer will include a “required items” section that specifies the type of battery you’ll need, and usually gives specific product recommendations.

This may seem like pretty basic advice, but we all had to learn it somewhere when starting out. The same rule applies when you pick out an RC battery charger to use with your new model. Get a charger that comes with a charging lead that has the same connector as the batteries you’ll be using. Again, follow the model manufacturer’s recommendations to be sure.

Compatibility is everything with RC battery connectors. Before you buy a battery, make sure that the connector’s female plug will fit the male plugs of your RC model and your RC battery charger.

Ease of installation

Choose an RC battery connector that will be easy to install using the skills and tools you already have. If you don’t have a soldering iron and have never soldered before, start with an RC battery connector that’s ready to use, with the lead attached, in the size recommended by your model’s instruction manual.

Current capacity

Before you buy an RC battery connector, check the maximum current draw in amps of your RC model’s electronic devices. You’ll find this information in the requirements section of the model’s instruction manual, packaging, or web page. For safe and reliable operation, your RC battery connectors must be able to carry that maximum current safely.

If the devices try to draw more power from the battery than the connector is capable of handling, resistance will occur. Heat will build up and reduce efficiency. In extreme cases, the RC battery connectors could even melt. That’s why you need to confirm that your RC battery connectors can withstand the current demands of your model’s electronics in order to provide the greatest efficiency and power.

Size and weight

The weight of your RC battery connectors may be a concern if you plan to use them in a small, lightweight model where every extra ounce might negatively affect performance.

Another size-related consideration is the length of the wire cables or leads attached to plugs of your RC battery connectors. This is extra important because each electrical device on board your model requires a specific number of amps to operate. By adding up the current requirements of all those devices, you’ll see the maximum amperage that your battery needs to deliver.

Here’s where the length of your RC battery connector cables comes into play. As mentioned earlier, when electricity flows through a battery cable, it encounters some resistance. The resistance causes a voltage drop at the end of the cable, as the cable absorbs a small amount of the current. The longer the cable is, the higher the voltage drop will be. If the voltage drop is high enough, some devices may not receive the power they need to work properly.

Until you’re sufficiently experienced, always follow the recommendations of your RC model’s manufacturer when choosing your accessories and completion items — including batteries and RC battery connectors. The manufacturer has tested the model thoroughly with a variety of equipment and knows what will give you the best results.

A wide assortment of RC battery connectors is available. Use whichever style you like after ensuring that it meets the requirements of your application. Over time, RC modelers often develop a preference and use that connector type consistently with multiple models. Standardizing your RC battery connectors like this does make life much simpler. You won’t need adapters to run your different models or to charge all of your batteries. Here’s a quick look at some of the most common RC battery connectors that are available.

T-Style (Tamiya) connectors

T-style connectors, also known as Tamiya connectors, are among the oldest types of RC battery connectors. Made of plastic, they handle current up to 10 amps and have a T-shaped design for easy hookup and removal. Though a bit outdated, you’ll still find them being used in low- to moderate-power applications, such as small electric RC planes, boats, and cars. T-style RC battery connectors are not recommended for use with LiPo batteries and may even melt or catch fire if used in demanding, high-performance RC applications.

Deans Ultra connectors

The unique bullet shape of Deans connectors is especially easy to insert and remove, but it also limits their versatility by making them incompatible with other RC battery connector types. Their current capacity is suitable for large RC planes, boats, and cars using 2S or 3S LiPo batteries, but they should not be used with 4S or larger packs. Deans connectors are best for applications requiring medium to high current draw.

XT connectors

XT connectors are available in a variety of current ratings including 30 amp, 60 amp, and 90 amp. The medium-size XT-60 in particular is a favorite of many RC hobbyists. You’ll often see the larger XT-90 in 1/8 scale and large-scale RC cars, because it’s able to handle high currents while being safe and easy to connect.

EC connectors

EC connectors are known for their reliability and high current capacity. The plugs are made of heat-resistant nylon and use a gold-plated contact surface to lower resistance and improve conductivity. They’re also easy to install, with a simple but secure snap-on connection. EC style RC battery connectors have a unique anti-spark feature to prevent sparks and shorts when being plugged in or unplugged. A variety of sizes are available — EC-2, EC-3, EC-5 — with the number referring to their diameter and pin spacing, in millimeters.

IC connectors

The IC connectors of Spektrum Smart LiPo batteries are an evolution of the EC connector family. The biggest difference is that the IC connector plug has a third tab that, together with a data wire in the lead, transfers health and charging information from Smart batteries to Spektrum Smart chargers. However, IC battery connectors are also backwards-compatible with EC connectors. That means if you’re running models that include older electronic devices with EC connectors, you can still power them with newer IC-equipped Smart batteries.

We’ll close with one last piece of advice. Adapters are available that will allow you to join the plugs of two different RC battery connector styles and make them compatible. But this is not a recommended practice, especially for high-power applications. The adapters create additional resistance and can generate a lot of heat in your electrical system. You can use adapters to join incompatible RC battery connectors as a temporary solution in low-powered RC models, but they should never be a permanent part of your setup.