Battery 52V 20Ah Hailong — 1040Wh Premium Downtube Battery

The 52V Advantage — More Power From the Same Motor

The most important performance characteristic of this battery is its voltage. Running a 48V-rated motor on a 52V battery pack is one of the most effective and underutilised performance upgrades in the e-bike conversion world. Higher voltage at the same current draw means more power delivered to the motor — peak power increases, acceleration sharpens off the line, and top-end speed improves noticeably compared to running the same motor on a standard 48V pack.

Equally important, higher voltage at equivalent power output means lower current draw — the motor and controller run cooler, wiring stress decreases, and component life extends under sustained hard use. This battery delivers all of these advantages in a downtube format that fits the same mounting brackets as a standard 48V pack.

1040Wh — Serious Long-Range Capacity

With a rated capacity of 20Ah at 52V nominal, this battery stores 1040Wh of usable energy — enough for an estimated 52–69km of range from a 250W–350W mid drive system under mixed conditions, and meaningful real-world range even from higher-output 750W–1500W motor systems under hard use. For daily commuters covering longer distances, weekend tourers, and cargo build operators who need maximum range between charges, the 1040Wh capacity puts this pack in the long-range category of the 52V downtube battery lineup.

Capacity in Context

The step up from the 48V 13Ah battery is significant — that pack stores 624Wh at a lower voltage, while this pack delivers 67% more energy at a higher operating voltage that sharpens motor performance across the entire power range.

Grade A 21700 LG 4800mAh Cells — Premium Chemistry

This battery is built on Grade A 21700 LG 4800mAh lithium-ion cells — a premium cell specification that underpins both the capacity and the long-term reliability of this pack. The 21700 format delivers higher energy density per cell than the standard 18650, enabling 1040Wh within the compact Hailong downtube footprint. LG cell chemistry is among the most respected in the lithium-ion industry for consistency, cycle performance and thermal stability.

Grade A selection ensures every cell meets the tightest internal resistance tolerances — consistent performance across every cell, even ageing across the full pack, and reliable BMS management through every charge cycle. The cycle life specification confirms this quality — ≥80% capacity retention after 800 full charge cycles. At one full charge per day, that represents over two years of daily riding before the pack reaches 80% of its original 1040Wh capacity. Under typical partial-charge usage patterns, practical service life extends significantly beyond that benchmark.

Voltage Window — 58.8V Full Charge to 42V Cut-Off

This battery operates between a full charge voltage of 58.8V and a discharge cut-off of 42V. At full charge, the pack delivers peak voltage for maximum motor performance and sharpest throttle response. As the pack discharges through its operating range, voltage declines gradually until the BMS enforces the 42V cut-off to protect the cells from deep discharge damage. The 16.8V operating window between full charge and cut-off delivers the full 1040Wh of energy across a voltage range that any 48V or 52V motor controller handles natively without configuration adjustment.

40A Continuous, 100A Peak Discharge

The discharge specification of this battery is built specifically for demanding motor applications. At 40A continuous discharge, the pack sustains up to 2080W of continuous power draw at 52V nominal — well above even the 1500W maximum motor rating this battery supports, providing substantial headroom against BMS protection thresholds under normal riding conditions. The 100A peak discharge current handles the high-amplitude current spikes during hard acceleration from a standstill without voltage sag or protective shutdown.

The Hailong Case — Industry-Standard Compatibility

The Hailong case is the most widely used battery enclosure format in the e-bike conversion and OEM market — recognisable by its sleek, tapered profile and standard mounting interface that fits the vast majority of bicycle down tube positions without modification. This battery uses the format to deliver the broadest possible frame compatibility across mountain bikes, hybrid frames, commuter platforms and custom build bases.

The Hailong mounting system uses a secure slide-and-lock mechanism that keeps the battery firmly in position across rough terrain while allowing tool-free removal for charging.

BMS — Comprehensive Active Protection

The integrated BMS provides active protection against every common lithium battery failure mode:

Cell balancing during charging ensures every cell in the series string reaches the same state of charge — the key mechanism that maintains capacity consistency across 800+ cycles and prevents early-ageing divergence between individual cells.

Compatible Motor Systems

This battery is compatible with the full range of 48V and 52V hub motor and mid drive systems from 250W through to 1500W.

For the full range of 48V and 52V compatible conversion kits across all motor formats and power levels, visit the Conversion Kit category page. For the complete battery range across all voltages and capacities, visit the Batteries category page.

Charging — 3A Standard, 5A Fast

This battery charges at a standard rate of 3A, delivering a full charge from empty in approximately 6–7 hours — suited to overnight charging routines that prioritise gentle charge current for maximum long-term cell health. For faster turnaround, the pack supports a maximum continuous charge current of 5A, reducing full charge time to approximately 4 hours. The BMS terminates charging automatically at the 58.8V cut-off regardless of charger output, eliminating overcharge risk at either supported charge rate.

Warranty and Returns

Every Battery 52V 20Ah Hailong purchased from All4eBikes is covered by a 12-month warranty against manufacturing defects, alongside a 30-day return window for complete purchase confidence.