Most 48V batteries at this price point come with a 25-30A BMS. The YLuBik Hailong packs a 50A BMS in a sub-230 dollar package, which changes what kind of builds this battery can support. That's not nothing.
Most 48-volt batteries available at this price point include a 25 to 30 ampere battery management system (BMS) to limit the amount of power being drawn from each battery cell. In contrast, the 50 ampere BMS provided with the YLuBik Hailong offers significantly more capacity and thus allows for more aggressive build designs.
The form factor is the standard Hailong style that many generic electric bicycles (e-bikes) ship with. The length of the battery is 379 millimeters. Width is 97 millimeters. Height is 137 millimeters. As such, it will fit into most battery trays mounted under the down tube that employ a 4-pin connection. The battery weighs approximately 11.9 pounds, which is consistent with most 48-volt, 18.2 Ah packs. The USB port located on the side of the battery provides the ability to charge a cell phone while operating the e-bike. This feature is becoming more popular in recent years but still worthy of mentioning.
Specifications and Build Quality
This is a 13 S7P arrangement - 13 separate series arrangements of seven parallel connected cells for a total capacity of 18.2 Ah. Therefore, there are 873.6 Watt-hours (Wh) of stored energy contained within this battery. Although the type of cells used are not identified in the product description, based upon this battery's cost, we expect them to be unbranded 2600 milli-ampere-hour (mAh) cells. The housing of the battery consists of plastic material and includes a rubber gasket surrounding the area of the seam to provide a measure of water resistance.
The included charger has an output rating of 54.6 Volts and 2 Amperes. Thus, a full charge of the battery will require approximately nine hours to complete using the stock charger. Again, this represents a relatively low charge rate and is beneficial for maintaining the health of individual cells within the battery. However, faster charging rates may be available from competing products that include chargers with ratings as high as three Amperes or five Amperes.
Important specifications summarized in one location:
- Nominal voltage: 48 volts
- Total capacity: 18.2 Amp-hours/873.6 Wh
- BMS: Continuous 50 amps
- Physical dimensions: Length = 379 mm. Width = 97 mm. Height = 137 mm
- Weight: Approximately 11.9 pounds
- Connector: Four-pin base + XT60 Discharge connector
- Included charger: 54.6 VDC at 2 amps
- Cycle life: Claimed cycle life over 1000 cycles
The 50A BMS is clearly the dominant specification offered by the YLuBik Hailong. Most competitor products in the budget range around 200 to 250 dollars typically offer a 25-40 A BMS. Therefore, the YLuBik Hailong has sufficient head room to supply sustained power levels to a 1,500 W motor without tripping its BMS.
BMS Design and Key Features
The YLuBik Hailong has a maximum discharge capability of approximately 2400 W, which is suitable for powering a 1500 W hub motor with moderate power loss due to internal losses. Note that if you have a controller capable of exceeding 50A continuous, your YLuBik Hailong will protect itself from excessive draw and shut-off.
As mentioned previously, the 4-pin connector serves as both a charging and disconnecting mechanism for the bike. The XT60 connector is generally well-suited for this type of application as it is widely used among DIY e-bike builders.
Note that the included locking mechanism is intended to prevent casual thieves from easily removing the battery from the mounting plate. We do not consider it to be particularly secure however. On the left hand side of the battery is a power button that turns off electrical flow to the bike when it sits idle between rides. The LED display indicates how much remaining charge exists within the battery via four distinct color-coded bars.
There is also a USB port located near the top center of the battery. It connects directly to a cell phone or GPS device and can charge devices while operating the bike. Additionally, there is a waterproof seal surrounding the seam of the plastic casing to prevent water ingress during wet weather conditions.
Range and Real World Performance
Range estimates depend heavily upon factors including how aggressively you ride, what type of terrain you encounter, whether you utilize throttle control versus pedal assist control and other variables. Assuming a typical 500 W hub motor and assuming full throttle operation consumes approximately 10 to 12 watt-hours/mile (Wh/mile), we estimate the usable range as follows:
- Pedal Assist Mode: Approximately 70-85 miles per charge (depending on terrain etc.)
- Full Throttle Operation: Approximately 35-45 miles per charge
Again, these represent rough estimates and actual ranges may vary significantly depending on multiple factors including hills encountered along the route, wind experienced en route, rider weight and tire pressure.
In addition to improved performance on hilly routes, another major benefit of having a 50-amp BMS is reduced loss of range to "tripping" caused by BMS overload.
Which Riders Are Suitable for This Product?
This product fits into a particular niche -- riders who desire at least 50 amps of continuous discharge capacity without spending more than around 300 dollars. If you operate an e-bike equipped with a 1500 watt motor utilizing a 40 amp controller, chances are most Hailong batteries priced similarly to this one lack sufficient BMS capacity to meet your needs. For more context on different battery options, check out our other battery reviews.
Additionally, as noted previously, this product is designed specifically for standard Hailong cases with a four-pin base fitting many generic e-bikes as well as DIY conversions and mid-drives.
Drawbacks include few existing customers with reviews regarding durability. There were only five reviewers at Amazon. Therefore, we cannot make assessments regarding long term reliability. However, YLuBik Hailong claims durability to exceed 1000 cycles and back this claim with a 90-day money-back guarantee and six-month warranty.
Therefore, it is less desirable for extremely lightweight riders or those requiring very compact batteries. The size of the case design exceeds most downtube-only mounts or customized mounts for batteries.
Frequently Asked Questions
Will this battery fit my Rad Runner or Super 73?
The YLuBik uses a standard Hailong case with a 4-pin base. Some Rad and Super 73 models use a different mounting system and connector. Measure your battery compartment first. Dimensions are 379 x 97 x 137mm.
How long does it take to charge?
The included 54.6V 2A charger takes about 9 hours for a full charge from empty. You can use a higher-amp 54.6V charger to speed this up, but the BMS limits charge input to a safe level to protect the cells.
Can I use this battery on a 52V system?
No. This is a 48V nominal battery (54.6V full charge). Running it on a 52V system with a higher voltage controller could damage the BMS or cells. Stick with 48V controllers only.
What motors are compatible?
The 50A BMS supports motors from 250W up to about 1500W peak. That covers most hub motors, mid-drives, and scooter motors in that range. Make sure your controller is rated at 50A or less.
Is the USB port useful while riding?
Yes, the USB port outputs 5V for charging phones, action cameras, or bike lights. It is weather sealed and runs off the battery, so it works as long as the battery is on. Riders find this handy for keeping GPS units charged on longer trips.
Does it come with a mounting bracket?
Yes, the battery includes a 4-pin base mounting plate with an XT60 discharge cable attached. You mount the plate to your frame, then slide the battery onto it. The locking mechanism secures it in place.
Check current pricing on Amazon for the YLuBik 48V 18.2Ah. It's worth comparing against other 48V Hailong packs on our comparison table to see where it lands on value.