Choosing the Right UAV Battery Connector

Unmanned aerial vehicles (UAVs) span a wide range – from tiny toy drones to high-end industrial platforms – each with very different power needs. The battery connector is critical for ensuring safe, efficient power delivery. Its choice affects current capacity, weight, reliability and safety.

Common UAV connectors include gold-plated bullet-style contacts (e.g. XT‑series and EC connectors), T-plug (Deans), and small JST-series plugs. These vary in size, current rating and plug design. For example, XT and EC connectors are keyed plastic plugs with large contacts for tens of amps, while JST‐PH or JST‐XH connectors are tiny 2–15 A plugs used on micro drones.

Selecting the right connector means matching the UAV’s power demands and form-factor. For instance, small consumer drones typically draw only a few amps (often using JST‑PH or XT30 connectors), whereas racing multirotors and larger commercial drones need 50–100 A, pointing to XT60/XT90 or similar heavy-duty plugs.

UAV Categories & Connector Needs

• Small Consumer Drones: These use lightweight batteries (often <3S LiPo) and draw modest current. Tiny 2–3 A JST‐PH or JST‐XH connectors (≈2 A per pin) are common, as are small XT30 plugs rated ~30 A. The priority is low weight and compact size; high-current plugs would be overkill.

• FPV Racing Drones: High-discharge quadcopters need connectors that handle ~30–60 A per battery. XT60 (≈60 A cont.), Deans T‑plugs (≈60 A), or 4 mm bullet connectors are typical. These connectors fit most ESCs (which often come with female 3.5 mm bullets or XT60 leads) and offer a good balance of current capacity and size. For very high-amp setups (e.g. 6S packs at 80 A+), XT90 or high-current bullet systems may be used.

• Industrial UAVs: Large drone platforms (e.g. agricultural or inspection drones) carry heavy batteries and draw 100 A or more. They often use industrial-grade connectors: XT90 (90 A cont.), Amass AS150/XT150 (100–150 A cont. with 6–7 mm banana contacts). These connectors have rugged housings, often screw‐on shrouds for strain relief, and some include anti-spark features (e.g. XT90S, AS150S) for safety. High-voltage (8S–12S) packs are common, so connectors rated to 500 VDC (all above are) are needed.

• Long-Range UAVs: Fixed-wing or long-endurance drones also use large batteries (often high-voltage packs). They require reliable high-current connectors (similar to industrial drones) but weight is very sensitive. Designers may use XT60 or JST‐VH in lightweight builds if currents are moderate, or XT90/AS150 if currents exceed 60 A. Connector choice balances low electrical loss (low contact resistance) with minimal weight.

Each UAV category demands connectors rated above the expected current draw, with some margin for safety and peak loads. For example, one source recommends using XT60 for loads ≲80 A and XT90 for ≳100 A.

Common Connector Types

• XT Series (XT30, XT60, XT90): These two-pin bullet-style plugs are ubiquitous in RC and UAV applications. All have 2 cylindrical gold-plated pins in a keyed nylon housing. XT30 (approx. 30 A) is used on very small drones. XT60 (≈60 A continuous, 120 A peak) is extremely common on hobby drones. XT90 (≈90 A continuous, 120 A peak) is thicker, for very high-current packs. Typical XT60 plating yields ~0.5 mΩ contact resistance; XT90 is larger (≈23.5 mm across) and ~0.3 mΩ. XT connectors lock firmly and are easy to solder (they accept 10–14 AWG wire). XT90S is an XT90 variant with an internal resistor to suppress sparks.

• Deans T-Plug: A compact polarized plug popular with racers. Rated around 50–60 A, Deans connectors have low contact resistance and a slim profile. They must be soldered with care (the flat blades are small) but are well-regarded for reliable 60 A service. Deans plugs fit many ESCs and are common on 1/10th scale models, but their continuous limit (~60 A) makes them less suitable above that.

• GC6010 battery connector : a high-current, low-resistance connector designed for demanding power applications. Supporting up to 120A, it offers reliable performance with flame-retardant housing, copper alloy terminals, and a secure locking mechanism to prevent accidental disconnection. Its user-friendly, polarized design ensures safe and efficient connections, making it ideal for UAVs, electric vehicles, energy storage systems, robotics, and portable power devices.

• EC Series (EC3/EC5): Bulleted connectors encased in blue nylon bodies. EC3 plugs (3.5 mm bullets) are rated ~60 A; EC5 (5 mm bullets) up to ~120 A; EC8 goes higher (~240 A). These are frequently used on larger LiPo packs and battery chargers. They mate securely and have low resistance (gold contacts), but their housings add bulk. EC5, in particular, is a common upgrade for high-power ESCs and packs.

• JST Series: Small friction-fit connectors used for low-current links. Common variants include JST‐PH (2 mm pitch, ~2–3 A) and JST‐VH/SM (~7.5 A). These appear on tiny drone batteries and internal wiring. They must not be used for high current; exceeding ~10–15 A risks melting the plastic. However, JST balance connectors (XH series) are standard for LiPo balance leads. Their main advantages are low weight and secure polarized mating, but soldering fine JST pins requires skill.

• Anderson Powerpole: Genderless modular connectors (often 15–45 A per pole) used in power and charging applications. A pair of stacked Powerpoles can handle 90 A or more. They’re durable, easy to swap, and tolerant of vibration. Anderson PP are more common in DC power supplies and amateur radio than in aircraft, but heavy battery chargers or ground equipment may use them.

• Specialized Connectors: Industrial and custom UAVs may use high-end connectors. For example, Amass AS150/AS150U connectors (7 mm banana inside a screw-shielded housing) carry ~150 A continuous. ACES and PDC series connectors (from aerospace markets) integrate power and signal pins for smart batteries. These offer extreme reliability (IP-rated sealing, keyed pin layouts) for critical systems, but are rare in hobbyist drones.

Each connector type trades off current rating, size, weight and ease of use. Table 1 summarizes XT60 vs. XT90 – two of the most common UAV power plugs – which highlights these trade-offs:

Feature	XT60	XT90
Continuous Current	≈60 A (up to ~120 A peak)	≈90 A (up to ~120 A peak)
Contact Resistance	~0.5 mΩ	~0.3 mΩ
Housing Diameter	19.5 mm	23.5 mm
Weight (pair)	~15 g	~28 g
Wire Gauge (Recommended)	12–14 AWG	10–12 AWG
Ease of Soldering	Easy (spacious solder wells)	Easy (large terminals)
Typical Applications	Hobby multicopters, robotics	Electric vehicles, industrial drones
Safety	No anti-spark option	Anti-spark variant (XT90S) available

Practical Advice

• Match Connector to Current and Battery: Always choose a connector rated above your peak current. For example, if a drone draws 50 A continuous, an XT60 (rated ~60 A) or Deans (60 A) is acceptable, but an XT30 or JST is not. For 100 A systems, use XT90 or AS150. Check manufacturer datasheets: RS PRO rates XT60 at 30 A continuous (60 A surge) and XT90 at 40 A (90 A surge), so leave ample safety margin.
• ESC/Battery Compatibility: Most ESCs come with female bullet leads (commonly 3.5 mm) or pre-wired XT60 plugs. Ensure your battery connector matches the ESC, or plan to rewire/adapt. For example, many LiPo packs ship with XT60 leads for 3–5 S batteries; if your ESC has bullet connectors, solder in matching bullets or use an adapter. Conversely, using a rare connector can make sourcing replacements harder. XT60 is ubiquitous, whereas XT90 or AS connectors may require special order.
• Availability and Cost: Standard connectors (XT60, EC5, JST, Deans) are mass‑produced and inexpensive. Specialty connectors (XT90S, AS150, ACES) cost more. Consider logistics: hobby drones benefit from cheap, easy-to-find parts, while custom industrial UAVs can justify pricier hardware.
• Mechanical Durability: In flight, connectors endure vibration. Look for high-temperature nylon housings (e.g. PA66, UL94-V0 rated) and gold-plated contacts. Some vendors specify mating cycles (e.g. XT90 ~1000 cycles). Heavy drones often use connectors with latches or screws (AS series) to prevent accidental unplugging.
• Safety Features: Reverse-polarity protection and spark suppression are valuable. Most connectors are keyed (you cannot plug them backwards). Anti-spark versions (XT90S, AS150S) include resistors so the main contacts mate after a small discharge path, greatly reducing arcing on connection. For LiPo batteries (which can spark dangerously), such features can extend connector life and improve safety.
• Weight vs. Conductivity: In drone design, every gram counts. Larger connectors carry more current and have lower resistance (less voltage drop and heat) but weigh more. For a light quadcopter, XT60 or even micro connectors may be preferred over heavier XT90/AS150, provided the current is within limits. High-end designs sometimes use unshrouded bullet connectors (just the gold pins with shrink-tubed wire) to save weight, but these expose live contacts and require caution.
• Ease of Assembly: Consider solderability and assembly time. XT and EC connectors have solder cups sized for thick wire, making them relatively easy to attach. JST and Deans require precise soldering. Modular systems (like Powerpole) can simplify in-field repairs. Ensure you have proper crimpers or soldering irons for the connector pins you choose.

Conclusion

Selecting the optimal battery connector depends on your UAV’s size, current demand, and operational context. Small, low-power drones typically use JST or small XT connectors, which are light but only handle a few amps. Mid-range multirotors and racers often standardize on XT60 or Deans plugs (≈60 A) because they balance size and capacity. For high-power/industrial drones, use heavier connectors – XT90, EC5 or Amass AS150 (100–150 A+) – which minimize voltage drop under load. Always verify the connector’s current rating and wire gauge (e.g. 10 AWG for >70 A) and choose keyed or anti-spark variants if available. In short: match or exceed the UAV’s power requirements, favor connectors with proven reliability, and consider availability and weight in your design. By systematically comparing specifications (current, resistance, weight) and practical factors (ESC compatibility, durability), manufacturers can confidently pick the best connector type for each drone application.