Surlon Power builds this pack for e-bike makers, retrofit workshops and rental fleets that want a dependable 36-volt energy source without moving up to a heavier 48 V system. This 36V 17.5Ah NCM lithium battery stores 630 Wh in a 10S5P layout — ten cells in series, five in parallel — which holds voltage steady under load and spreads current across five cell groups instead of three. A 30 A battery management system sits inside the sealed case.
Before you commit, check the frame or rack space against the dimensions in the specifications. NCM chemistry is chosen for energy density: it puts more watt-hours into a given volume than LiFePO4 does, which is exactly what a bicycle frame rewards. The lock, charging inlet, discharge outlet and level display are already built into the housing, so the pack arrives as a finished unit rather than a kit of parts.
A sealed case only helps if what sits inside it can take punishment, so the pack pairs long-life cells with a 30 A battery management system that reads cell voltage, current and temperature continuously. It stops charging on over-voltage, cuts discharge before deep discharge can damage the cells, trips on short circuit and shuts down when temperature climbs. It also balances the ten cell groups against each other, which is what keeps a 10S5P pack delivering even power in its third year instead of sagging on the first long climb of the day.
The BMS is rated at 30 A continuous, and inside a bicycle that rating sets the working ceiling for the motor. The specification lists a 40 A maximum discharge current, which is a short-duration figure rather than a rating you can hold for a whole climb. If your controller pulls more than 30 A for long stretches, tell our engineers the controller model and the duty cycle and we will review the configuration with you before you order. A low-voltage switch lets you isolate the pack completely when the bike is parked for weeks.
Range figures are only useful when you know how they were produced. On a controlled test route, this 36V 17.5Ah NCM lithium battery returns up to 70 km when the motor is ridden softly in ECO mode, and up to 50 km when it is pushed hard in TURBO. The 20 km difference is the price of assist level, and it is the honest way to read the pair: the same pack, two very different riding styles.
Rider weight, payload, tyre pressure, hills, headwind and air temperature all move the number further, and a cold morning costs range before the pack has warmed into its working window. For a fleet, do not plan on the test figure. Run your own route with a rider of typical weight, log the distance in each assist mode, and use that as the planning number. Then decide whether one pack per bike is enough or whether the depot needs a spare per shift — that decision is worth far more than a brochure claim.
| Product code | 36V17.5Ah |
| Nominal voltage / capacity | 36 V / 17.5 Ah |
| Stored energy | 630 Wh |
| Cell configuration | 10S5P, NCM |
| Internal resistance | ≦200mΩ |
| Weight | 3.6Kg |
| Dimensions (L × W × H) | 378 × 78 × 114 mm (14.9 × 3.1 × 4.0 in) |
| Charging limit voltage | 42V |
| Standard / maximum charging current | 2 A / 5 A |
| Discharge cut-off voltage | 27V |
| Standard / maximum discharge current | 3 A / 40 A |
| Working temperature | charging:0~50℃discharging:-30~60℃ |
| Storage temperature | 1 years:-20~25℃3 months:-40~45℃1 month:-40~60℃ |
| Low-voltage switch | yes |
| Charging port / discharging port | DC2.1 / 3-pin |
A durable, sealed housing holds high-quality cells built for a long service life, together with a microprocessor-controlled battery management system that continuously monitors the battery's operating parameters. That system provides the protections needed for safe everyday use — against deep discharge, overcharging and overheating — and balances the voltage between cells to extend battery life. The built-in 30A BMS also feeds the motor with a strong, steady supply of energy, so you keep maximum performance even on the steepest climbs and can use the full potential of your e-bike.
Technical questions reach the people who build the packs. Our engineering group in Shenzhen reviews your device's voltage window, load profile, enclosure space and charger before proposing a configuration; our sample group then builds units so you can validate fit and runtime before production. Cell selection, BMS design and pack assembly stay in-house, with quality checks in process and at final inspection, and a documentation team handling certificates, test reports and shipping papers. When a unit behaves unexpectedly in the field, our engineers help trace the fault and advise on installation and commissioning.
Voltage, capacity and cell configuration are the usual starting points, and the port arrangement — charge inlet, discharge outlet and connector type — can be changed to match a bike's wiring layout. For a custom e-bike battery pack project, send the frame drawing, the controller specification and the distance you need per charge, and our engineering team will come back with a proposed configuration plus the points we need you to confirm.
The BMS is the gatekeeper between the cells and your controller. It measures voltage, current and temperature, opens the circuit when a reading leaves its range, and balances the cell groups so capacity stays even across the pack. Because it is rated at 30 A, it also decides how much current the motor can draw continuously — that figure, not the cell count, is what you match against your controller.
That is what it is built for. 630 Wh and a five-cell-parallel layout give a 36V battery pack for electric bicycles the reserve for long commutes and multi-stop shifts, and the sealed housing and BMS are specified for daily charge cycles rather than occasional weekend use. Fleets usually add a spare pack per bike so a depleted unit can be swapped out and charged off the machine.
One with a 42 V limit and a DC2.1 plug. 2 A is the standard charging current and 5 A the maximum, so a faster charger is fine only if it stays inside those numbers and the pack is between 0 °C and 50 °C while charging. If you want to keep a charger you already own, have it checked against the 42 V limit before the first charge.
Measure the frame or rack space with the lock, the cable bend and the bracket in place, then confirm the connector plug matches the 3-pin discharge outlet and the DC2.1 charge inlet. Send us a photo or drawing of the mounting area if you want it checked against our drawing before you order.
Discharge is rated from −30 °C to 60 °C, so the pack keeps working on a cold morning. Charging is the tighter window at 0 °C to 50 °C: let a cold pack come up to room temperature before you plug it in. Expect usable range to drop in low temperatures, as with any lithium pack, and plan winter routes with that margin in mind.
