RC Battery Connector Types: Complete Guide to LiPo Connectors

RC battery connectors transfer power from your LiPo or NiMH battery pack to your ESC (electronic speed controller) and motor. Choosing the wrong connector type risks poor performance, overheating, or damaged electronics. The right connector ensures efficient power transfer and keeps your RC car running safely.

This guide covers 12 common RC battery connector types with their amp ratings, wire gauge requirements, and best applications. Doesn't matter if you're running a 1/10 scale basher on 2S LiPo batteries or a 1/8 scale buggy on 6S, because you'll find the right plug for your setup. We'll also explain balance connectors, soldering tips, and how to match connectors across your battery, ESC, and charger.

RC Battery Connector Comparison Chart

Before we get into the details of each connector type, here's a quick reference showing the most common RC connectors used in the hobby. This table compares amp ratings, wire gauges, and typical applications so you can quickly identify which connector fits your needs.

Connector Type	Amp Rating	Wire Gauge	Best For	Common Brands
XT-60	60A	12-14 AWG	1/10 scale, 2S-4S LiPo	Hobbywing, Team Corally
XT-90	90A	10-12 AWG	1/8 scale, 4S-6S LiPo	Team Corally, bashers
XT-30	30A	16-18 AWG	Receiver batteries, mini scale	Various
Deans/T-Plug	60A	14 AWG	2S-3S setups	HPI, Maverick
EC-3	60A	12-14 AWG	1/10 scale	Horizon Hobby brands
EC-5	120A	10-12 AWG	High-power 1/8 scale	ARRMA compatible
IC-5	120A	10-12 AWG	ARRMA/Spektrum ecosystem	ARRMA, Spektrum, Axial
TRX iD	75A	12 AWG	Traxxas vehicles	Traxxas
Tamiya	15A	14-20 AWG	NiMH, beginner RTR	Tamiya, budget RTR
4mm Bullet	90A	14 AWG	Chargers, racing	Competition batteries
5mm Bullet	120A	12 AWG	High-current racing	Competition batteries

If you're shopping for best LiPo batteries for RC cars, pay attention to which connector comes pre-installed. Many batteries ship with XT-60 or Deans plugs, but Traxxas and ARRMA batteries use their proprietary connectors. You can always swap connectors later, though matching them from the start saves time.

Browse our full selection of RC cables, connectors and adapters to find the exact plug you need. Now let's look at each connector type in detail, starting with the most popular choice for modern RC applications.

RC Battery Connectors

RC battery connectors can withstand high currents and voltages while being sturdy enough for hundreds of connection cycles. These connectors are often color-coded for easy identification, with yellow typically indicating XT connectors, red for Deans, and blue for EC types.

Quality matters here. Cheap connectors with poor gold plating or thin terminals create resistance, generate heat, and can even cause fires. Stick with name-brand connectors from reputable manufacturers like Amass (XT series), and avoid the cheapest options you find online.

One thing to keep in mind: your connector must match between battery, ESC, and charger. If your ESC uses XT-60 but your battery has Deans, you'll need an adapter or a soldering session. Our guide on ESC and motor choice helps you match all your electronics properly.

XT Connectors (XT-30, XT-60, XT-90)

XT connectors are widely used in the RC hobby and have become the preferred choice for many RC enthusiasts and manufacturers alike. They feature gold-plated bullet terminals molded into a heat-resistant nylon housing that can't be connected backwards.

The XT-30 is the smallest of the family, rated for 15-30 continuous amps. You'll see these on receiver batteries, mini quads, and auxiliary equipment like crawler winches. They use 2mm bullet-style contacts and work well for anything drawing under 30 amps.

XT-60 connectors sit in the sweet spot for most RC applications. Rated at 30-60 amps continuous (with higher burst ratings), they fit 1/10 scale vehicles perfectly. The 3.5mm gold-plated contacts provide low resistance, and the keyed housing prevents reverse polarity. Many RC chargers now use XT-60 as their default battery connector, replacing the traditional 4mm bullet leads.

For larger RC models, XT-90 connectors handle 60-90 continuous amps. You'll find these on 1/8 scale buggies, truggies, and power-hungry bashers. The 4.5mm contacts and larger housing dissipate heat better under sustained loads.

The newest XT-60 versions feature gray or black cable covers that don't require heat shrink tubing. When soldering any XT connector, work quickly because the nylon housing can melt if exposed to heat for too long.

Amass Electronics designed and patented the original XT connector series. While many manufacturers now produce compatible versions, genuine Amass connectors offer the best quality. Browse our selection of connectors to find XT plugs in all sizes.

Deans (T-Plug) Connectors

Deans connectors (also called T-plugs or "red connectors") were among the first connector types designed specifically for high-current LiPo batteries. They remain popular today, especially on RTR cars from HPI Racing and Maverick RC.

The design uses two spring-loaded terminals arranged at 90 degrees to each other. This shape makes it impossible to connect backwards, which is a genuine safety feature for beginners who might otherwise fry their electronics. Deans connectors handle 60-75 amps and work best with 2S-3S LiPo configurations.

So are Deans connectors outdated? Not exactly. They still work fine for their intended purpose, but they have limitations. The tight connection can be difficult to pull apart, especially with cold fingers at the track. The plastic body is heat-sensitive during soldering, and genuine Deans plugs are harder to find than clones of questionable quality. If you're building a new setup from scratch, XT-60 is probably the better choice. But if your existing gear uses Deans, there's no urgent need to switch everything over.

The original Deans Ultra Plug was designed and manufactured by WS Deans of Los Alamitos, California, which is how this connector type got its name.

EC Connectors (EC-2, EC-3, EC-5)

EC connectors share a similar concept to XT connectors but with one key difference: the bullet pins are separate from the plastic housing. This makes soldering easier because you attach the wire to the pin first, then press the pin into the housing afterward.

EC connectors come in three common sizes. EC-2 uses 2mm bullets and handles around 20 amps, suitable for small electronics. EC-3 features 3.5mm contacts rated for 60 amps, making it comparable to XT-60 in performance. EC-5 connectors use 5mm bullets and handle up to 120 amps for high-power applications.

The blue plastic housing is the easiest way to identify EC connectors. Unlike XT connectors where the pins are permanently molded in, EC pins can be removed and replaced if damaged. However, the separate design means the housing isn't quite as robust under stress.

Here's where it gets interesting for ARRMA owners: EC-5 connectors fit directly into IC-5 connectors. This means you can use aftermarket batteries with EC-5 plugs in your ARRMA vehicle without any modifications. You just won't get the Smart battery features.

IC Connectors (IC-3, IC-5)

IC connectors represent the next step in the EC connector family, developed by Spektrum Smart Technologies for use in ARRMA vehicles and other Horizon Hobby brands like Axial and Losi.

The key difference is the third pin that carries data between the battery and charger. Spektrum Smart batteries use this connection to communicate charge history, cycle count, and individual cell voltages. The integrated balance connector eliminates the separate balance lead found on traditional LiPo battery packs.

IC-3 and IC-5 sizes correspond to their EC counterparts (3.5mm and 5mm contacts respectively). They're backwards compatible, meaning an EC-5 battery plugs right into an IC-5 ESC. However, you'll only get Smart features when using Spektrum Smart batteries with a compatible charger.

For RC enthusiasts invested in the ARRMA ecosystem, IC-5 connectors make sense. For everyone else, EC-5 or XT-90 provides the same electrical performance without the proprietary element. Our Traxxas versus ARRMA comparison explores more about how these brand ecosystems differ.

Traxxas iD and TRX Connectors

Traxxas designed their proprietary connector system to make battery charging foolproof. The TRX iD connector includes integrated balance leads and communicates with Traxxas EZ-Peak chargers to automatically configure charge settings.

The connector itself is robust, with spring-loaded contacts rated for 75 amps continuous. A large plastic tab prevents reverse polarity, and the size of the contacts keeps resistance low. Traxxas claims their connector has 24.5 times less resistance than a standard Molex connector, though that comparison is a bit apples-to-oranges since nobody uses Molex for power connections in RC.

The older TRX connector (pre-2017) looks similar but uses a separate balance lead instead of integrated balance contacts. Both versions are backwards compatible, so older batteries work in newer Traxxas vehicles.

If you're soldering TRX connectors, attach the wires to the terminals first, then press them into the housing. The plastic body handles heat better than some other connectors, but you should still work efficiently.

For detailed information about Traxxas battery systems, see our guide on Traxxas iD high current connectors explained. If you're shopping for Traxxas-compatible batteries, check out how to buy a battery pack for your Traxxas vehicle.

Bullet (Banana) Connectors

Bullet connectors (sometimes called banana plugs) deliver the lowest resistance of any connector type. There's no plastic housing to get in the way, just pure metal-to-metal contact across a large surface area.

Sizes range from 2mm up to 8mm, with 4mm and 5mm being the most common in RC applications. Current ratings scale with size:

Size	Current Rating	Wire Gauge
2mm	25A	20 AWG
3.5mm	50A	16 AWG
4mm	90A	14 AWG
5mm	120A	12 AWG
5.5mm	130A	12 AWG
6mm	150A	10 AWG
8mm	200A	8 AWG

The simplicity comes with serious risks. Since both cables move freely, short circuits happen easily if the connectors touch while connected to a battery. There's also no polarity protection, meaning it's possible to connect a battery backwards and destroy your electronics instantly.

Many RC chargers use 4mm bullet connectors as their default battery lead because they're compatible with the widest range of battery types. When you finish charging, disconnect the battery from the cable first to avoid any chance of a short circuit.

Competition racers still prefer bullet connectors for their low resistance, but they require experience and caution. If you're new to the RC hobby, stick with housed connectors like XT-60 until you're comfortable with electrical safety. For help picking a charger, see our guide on how to choose a RC charger.

Team Corally PRO 3.5mm Connector

Team Corally developed their own take on the 3.5mm housed connector. At first glance, it resembles an XT-60, but longer polarity tabs inside the housing provide extra protection against reverse connections.

The electrical performance matches XT-60, with 30-60 amp capacity and 12-14 AWG wire compatibility. The key difference is that Team Corally PRO connectors don't mate with XT-60 connectors due to the different polarity tab design. If you use Team Corally batteries and ESCs, this isn't an issue. But if you're mixing brands, you'll need adapters or connector swaps.

Team Corally offers a wide range of quality RC accessories beyond just connectors.

Tamiya and Tamiya Mini Connectors

The Tamiya connector has been around since the 1970s, making it the grandmother of all RC battery connectors. Despite its age, you'll still find it on many NiMH battery packs and beginner RTR vehicles.

The design is lightweight with a plastic locking clip that keeps the connection secure. Standard Tamiya connectors are white and slightly transparent, while the smaller Mini version has a light green color for 1/18 and 1/24 scale vehicles.

Here's the problem: Tamiya connectors only handle about 15 amps. That was fine for brushed motors and NiMH batteries in the old days, but modern brushless systems easily exceed that. Using Tamiya connectors with LiPo batteries or high-powered brushless setups risks overheating, melting, or even fire.

If your RTR car came with Tamiya connectors and you want to upgrade to LiPo batteries and brushless power, plan on swapping to XT-60 or Deans connectors. It's not difficult, just a quick soldering job.

One odd note: some airsoft guns use Mini-Tamiya connectors with reversed polarity, where the square terminal is negative instead of positive. This doesn't apply to RC cars, but it's worth knowing if you're sourcing connectors from general electronics suppliers.

For RC enthusiasts just starting out, cars with Tamiya connectors and NiMH batteries are perfectly fine for learning. Check out our list of best Tamiya RC cars or the broader best RC cars for beginners guide.

All the connectors above handle the main power connection between your battery and ESC. But if you're running LiPo batteries, there's a second connector you need to understand.

RC LiPo Balance Connector Types

Beyond the main power connector, LiPo batteries have a second plug called the balance connector. This smaller connector lets your charger monitor and balance individual cell voltages during charging, which is necessary for battery safety and longevity.

The JST-XH connector is the standard balance connector type used in the RC hobby. The number of pins corresponds to the cell count plus one: a 2S battery has 3 pins, a 3S has 4 pins, a 4S has 5 pins, and so on. The white plastic housing and small pitch make them easy to identify.

You'll connect the balance lead to your charger's balance port alongside the main power connector. The charger uses this connection to measure each cell and adjust charging current to keep all cells at the same voltage. Without balance charging, cells can drift apart in voltage, leading to reduced capacity, puffing, or worse.

Some connector systems like Traxxas iD and Spektrum IC-5 integrate the balance connector into the main power plug. This is convenient because you only have one connector to deal with, but it locks you into that brand's ecosystem for chargers.

For a deeper look at balance charging, our balancer harness buyer's guide covers the different board types and adapters available. You'll also want to read how to use and charge LiPo batteries for safe charging practices.

Understanding cell counts and their relationship to voltage is important when working with balance connectors. Our guide on LiPo battery markings and meanings explains what all those numbers on your battery pack actually mean.

General Use RC Connectors

Not every connector in your RC car handles high-current battery power. Servos, receivers, ESC signal wires, and accessories use smaller connectors designed for low-current signal transmission.

Servo Connectors (Futaba/JR/Hitec)

Servo connectors are the standard for anything that plugs into your radio receiver. They've been used in RC since the early days and remain universal across nearly all manufacturers.

These 3-pin connectors carry power (positive and negative) plus a signal wire. The color coding is usually red for positive, black or brown for negative, and yellow or white for signal. Some cables use a single color for all three wires, so always check the polarity before connecting.

Futaba-style housings have a small tab that prevents wrong-way insertion, while JR/Hitec housings have a beveled edge instead. Both types fit into most receivers, though the connection may be slightly looser depending on the combination.

The 0.1" pitch terminals are the same ones used in computers and general electronics, making these connectors easy to source and crimp. For more powerful servos drawing higher current, use heavier gauge wire (20 AWG instead of 24 AWG) to reduce voltage drop.

Our guide on how to choose a servo covers servo selection in detail. You can also browse our servos category to see what's available.

JST-XH (Balancer Cable Connector)

We mentioned JST-XH connectors in the balance connector section, but they deserve their own mention here. These connectors are commonly used in LiPo battery balancer cables and feature multiple pins in a white plastic housing.

JST-XH connectors are rated for about 3 amps, which is plenty for the low-current balance monitoring function. They're built by crimping wires to terminals and pressing them into the housing. The fit is snug but not locking, so they can pull apart under strain.

One common point of confusion: "JST connector" isn't specific enough. JST (Japan Solderless Terminal) makes dozens of connector families. In RC, we typically use JST-XH for balance leads and JST-RCY for BEC connections. Calling something a "JST connector" without specifying the type can lead to ordering the wrong part.

JST-RCY (BEC Connector)

The JST-RCY is the red 2-pin connector you'll find on external BEC (Battery Elimination Circuit) units, receiver batteries, and crawler accessories like winches.

Unlike JST-XH, the RCY has a locking tab that clicks into place and requires you to press a release to disconnect. This makes it more secure for applications where vibration might shake a connection loose. The larger terminals handle 5-10 amps, which exceeds what most accessories draw.

If you're not familiar with BEC systems, they're essentially voltage regulators that power your receiver and servos from the main battery pack. Most ESCs have a built-in BEC, but some high-power setups require an external BEC for reliable receiver power. For more on how ESCs work, check out our article explaining what is ESC.

Now that you know the different connector types, here's how to install them properly.

How to Solder RC Battery Connectors

Proper soldering is what separates a reliable connection from a heat-generating weak point. Bad solder joints create resistance, which generates heat, which can melt plastic housings or damage electronics.

The basic process for any connector involves tinning both surfaces first. Apply solder to the wire and the connector terminal separately, then bring them together and add a little more solder to join them. This creates a strong mechanical and electrical bond without cold joints.

For housed connectors like XT-60, Deans, and EC types, work quickly. These plastic housings can melt or warp if exposed to heat for too long. Some RC drivers use a connector holder or helping hands to keep the connector steady while they work.

Heat shrink tubing adds insulation and strain relief to your connections. Slide it onto the wire before soldering, then position it over the joint and apply heat from a heat gun or lighter. Many modern XT-60 connectors come with integrated covers that eliminate this step.

For detailed soldering instructions, read our complete guide on how to solder RC connectors. If you're swapping connector types on an existing battery or ESC, how to change battery plugs walks through the process step by step.

You'll need a decent soldering iron (60W minimum for larger connectors), quality solder, and basic tools. Browse our soldering tools category for everything you need.

Still have questions? Here are the most common ones we hear about RC battery connectors.

RC Battery Connectors FAQs

Can you mix different connector types on RC batteries?

Adapter cables connect mismatched plugs but add resistance and potential failure points. For occasional use or charging, adapters work fine. For permanent setups, solder matching connectors on batteries and ESC for best performance. Adapters generate heat under sustained loads and create extra connection points that can loosen over time.

Are RC battery connectors universal?

RC battery connectors are not universal. Traxxas uses proprietary TRX iD connectors, ARRMA uses IC-5 (EC-5 compatible), and aftermarket batteries typically come with XT-60 or Deans plugs. Before buying batteries or upgrading electronics, check which connector your ESC and charger use to avoid compatibility issues.

What causes RC connectors to overheat?

Undersized connectors, poor solder joints, and dirty contact surfaces cause RC connectors to overheat. Use connectors rated 20% above your peak current draw. Inspect solder joints for cold joints (dull, grainy appearance) and clean contact surfaces with electrical contact cleaner. Resistance at any connection point generates heat.

XT60 vs XT90: which is better?

XT60 handles 30-60 amps for 1/10 scale vehicles with 2S-3S batteries. XT90 handles 60-90 amps for 1/8 scale vehicles and 4S-6S configurations. Neither is universally better. Choose XT60 for compact installations and moderate power. Choose XT90 for sustained high current draws and larger vehicles.

Are Deans T-Plugs outdated?

Deans connectors work fine for 2S-3S applications under 60 amps but most hobbyists now prefer XT-60. Deans are harder to solder due to heat sensitivity, difficult to disconnect because of tight fit, and genuine plugs are scarce compared to variable-quality clones. New builds should use XT-60.

Which connector gives the lowest resistance?

Bullet connectors (4mm and larger) provide the lowest resistance due to their large, simple contact surface. Among housed connectors, XT-90 and EC-5 offer excellent low-resistance connections with gold-plated contacts. Deans have slightly higher resistance. Racing applications favor 4mm or 5mm bullets despite short-circuit risk.

Wrapping Up

Keeping your connectors organized saves frustration when you're looking for a specific adapter or replacement plug. Small terminals are easy to confuse with each other, so store them in a divided parts box and keep it in a dry place.

If you're not sure which connector type you need for your RC car or have questions about compatibility, our EuroRC customer service team is here to help. Send us a photo of your current setup to info@eurorc.com and we'll point you in the right direction.