Hailong E-Bike Battery Case — Variant Identification Guide

"Hailong" is not a brand — it is a style of downtube case adopted by many manufacturers, used on countless DIY conversions and budget/import e-bikes. That makes it the most widespread case out there, but also the one where "it is a Hailong" tells you almost nothing on its own. You have to identify the variant.

Schematic of a Hailong e-bike battery case showing where to measure length, the connector and mount, the voltage label, and the charge port. — With Hailong, the mount bolt pattern and connector matter as much as the length.

What decides fit

Variant — No.1, No.1 Type 2, No.2/Max, Pro, Plus, and the modern G56/G70/G80. Similar look, different sizes and mounts.
Mount bolt pattern — the original No.1 tray uses up to 4 bolts; others differ. The mount must line up with your frame.
Discharge connector — same-size cases ship with 4-pin and 5-pin plugs that are not interchangeable.
Voltage — Hailong cases exist in 36/48/52V. Match your bike and controller.

The original No.1 tray was designed for low-power 24–36V packs and its connector struggles with high-current 48/52V builds. For a modern high-power pack, the G56/G70/G80 tray — stronger locking tabs, four mounting holes, beefier pins, and 21700 cells on the G80 — is the one to prefer.

Hailong case-identification guides

Hailong No.1 — Hailong No.1 & No.1 Type 2 (a.k.a. 'Hailong III')
Hailong No.2 / Max — Hailong No.2 (HL-2) & No.2 Max
Hailong G56 / G70 / G80 — G56 / G70 / G80 (modern upgraded tray)

These are identification guides, not single-bike fitments: confirm your variant, mount, connector and voltage against your own case before buying.