E-Bike Connectors Explained: XT60, XT90, Anderson, Julet and Higo

High-current battery connectors: XT60, XT90 and Anderson

XT60 and XT90 are yellow (sometimes black or blue) nylon plugs with two large bullet contacts. They are rated for roughly 60 and 90 amps respectively and are widely used to connect battery to controller on conversion kits, DIY builds and some complete bikes. The XT90 has a larger body and is often used in an anti-spark version with a small resistor in one contact to prevent the pop when you connect a charged battery. They are polarized and cannot be plugged in backward.

Anderson Powerpole connectors are modular, usually red and black, and common on older Rad Power, Juiced and many kit bikes. They are genderless and the housings slide together; the risk is that they can be assembled with the wrong polarity orientation, so match the color and the dovetail pattern of the originals exactly if you ever replace one. They handle 30 to 45 amps in the sizes used on e-bikes.

Many complete bikes from Aventon, Lectric, Heybike and similar brands use a battery that slides onto a mount with spring contacts, and the high-current connector to the controller is a brand-specific plug inside the frame. You will rarely touch those. Where you will see XT or Anderson is at the controller input on a kit, or at the discharge lead of a battery sold separately.

Julet and Higo signal connectors

The small round waterproof connectors on nearly every hub-motor e-bike are made by Julet or Higo, two Chinese connector makers whose products are close to interchangeable in the common sizes. They have a molded body, a rubber seal, a threaded or push-fit sleeve, and between two and nine pins. Each is keyed with an arrow or a flat so it only goes together one way. The display usually uses a 5-pin, throttle 3-pin, brake sensors 2- or 3-pin, pedal assist sensor 3-pin, and the motor a large 9-pin with three thick phase wires and five thin hall-sensor wires plus a speed signal.

The color of the connector body does not indicate function; pin count, size and the mating key do. Two 3-pin Julet connectors of the same size will physically mate even if one is a throttle and the other a pedal sensor, so label cables before unplugging more than one. A common pattern on Bafang-style systems is a single 1T4 or 1T5 harness from the controller that splits into display, throttle and brake leads; if one branch fails, the whole harness is replaced.

Signal connectors corrode and loosen. A bike that cuts out over bumps, a throttle that works intermittently or a display that flickers often traces to one of these plugs. Unplug it, look for green or white deposits and bent pins, clean with contact cleaner, and reseat firmly with the arrows aligned. That is a safe check anyone can do.

Charge ports and other plugs

The charge port on the battery is a separate connector family: round DC barrel jacks in several sizes, 3-pin XLR on many Rad Power and older bikes, and brand-specific ports on premium systems. Our charger guide covers matching these. Some batteries also have a small discharge port for lights or a USB port for phones; these are low current and separate from the main leads.

Lights wired to the main battery use small 2-pin Julet-style plugs carrying battery voltage stepped down by the controller, typically 6V, 12V or full pack voltage depending on the bike. Match the light's voltage to what the bike supplies before plugging in a replacement. Brake lever cut-off sensors are usually 2-pin and normally open or normally closed depending on the controller; swapping in the wrong type makes the motor refuse to run, which our wont accelerate page covers.

Identifying a connector and buying a replacement

To identify a signal connector, count the pins, measure the outer diameter of the body, note whether it is male or female (pins or sockets) and whether it has a threaded collar. Photograph it next to a ruler. Listings for Julet and Higo cables specify pin count and often the function, and a matching pin count and size will mate. Buy a short extension or a pigtail rather than a bare connector unless you are equipped to crimp.

For XT and Anderson, buy the same series and, for Anderson, the same contact size. Replacing one end of a high-current connector means cutting and soldering or crimping battery-voltage wire, and a poor joint gets hot. Unless you have done it before and have the tools, this is a job for a shop. A pin extractor and a proper crimp die make Julet repairs feasible at home; a pair of pliers does not.

Safety notes

Always turn the bike off and, where possible, remove the battery before unplugging anything. The motor phase wires and battery leads carry enough current to weld a ring or melt a tool. Never short the battery discharge contacts. Never connect or disconnect the high-current battery plug under load, and if you get a spark on connection, that is normal on a non-anti-spark plug but not something to do repeatedly.

If a connector is melted, browned or smells burnt, the cause is usually a poor contact or an overload and it will recur until fixed properly. Do not tape it and keep riding. That is the point at which to use the E-Bike Assessment or take the bike to someone who does this for a living.