The battery is the most likely thing to die on an older ebike. The motor continues to spin. The controller starts firing up, but the pack stops working about halfway through the hill you were able to climb without breaking a sweat. It is at that exact moment that you begin looking for a new battery. A Gofaro 48V 20Ah replacement battery is the type of product you will search for when you want to get your bike rolling again quickly, but you don't want to mortgage the garage to do it.
The Gofaro is a generic replacement pack sold as a replacement for 48V systems. As such, the primary specification to look at is the capacity, in this case 20Ah (which equates to approximately 912 to 960 watt-hours). The listing also includes a claim that it supports motors rated up to 1500 watts. Given that a 1500-watt motor draws approximately 30 amps at peak (and possibly higher), there had better be a good deal of headroom in the BMS for it to prevent a fire when being drawn upon aggressively. Although this is not explicitly stated in the listing, it is implied based on the listing alone.
As you can imagine, the main concern with any replacement pack is build quality. Unfortunately, no cell brand information is provided by Gofaro in their listing. Instead, they describe this as a "universal" replacement pack intended for generic bikes purchased directly from manufacturers that also included generic batteries. If you are accustomed to sealed, locked-down replacement packs from well-known manufacturers, this will appear more utilitarian. This is simply what budget replacement packs are.
In terms of fitment, this pack is described as a generic "other" form-factor pack. Therefore, the likelihood that it will fit your bike without additional modification and/or adapter hardware is questionable. Verify the mounting position, size and shape of your existing battery tray, and the connectors before committing. The greatest risk associated with purchasing this pack is fitment.
Safety Features
The feature you should really care about is the BMS. According to Gofaro, their BMS is capable of supporting 1500W motors. As such, when drawing 30 amps (or greater) from these motors, the BMS should provide sufficient current to prevent overheating and/or ignition. There are two important caveats related to this. First, the BMS may not provide sufficient margin above maximum current requirements to allow for aggressive acceleration, meaning rapid deceleration followed immediately by rapid acceleration. Second, the BMS may fail due to excessive heat generated during prolonged high-current operation. Gofaro lists compatibility with 1500W motors but does not provide specifics regarding its BMS design or functionality. Therefore, we cannot make a determination regarding how reliable it will be.
If we assume a competent BMS will protect against the four major failure modes associated with lithium ion packs (overcharge, over-discharge, over-current and shorts), then our assumption is valid. However, given that this is a budget replacement pack priced significantly lower than comparable replacement packs from reputable manufacturers, we are essentially wagering that this BMS provides adequate protection against each of these failures. While there are few assurances available relative to the BMS design/implementation in this pack, one positive aspect is the high capacity of the pack. Since the pack stores 912Wh of energy, you will be placing less stress on individual cells per ride compared to a smaller pack, which generally results in increased longevity. That represents another strong argument for selecting more capacity than necessary.
Estimated Range and Real World Performance
Estimated range is perhaps where a 20Ah 48V pack truly shines. On a typical 500W to 750W motor with moderate pedaling assistance, you can reasonably expect estimated ranges of approximately 30 to 45 miles per charge cycle. When operating a 1500W motor at maximum power output however, you can reasonably expect a much reduced range, potentially as low as 15 to 20 miles, assuming you operate the motor at maximum power output continuously.
Many factors affect your range including rider weight, terrain, tire pressure, wind resistance, etc. Using a pack of this size provides you ample buffer space so that you will rarely be concerned with reaching your destination prior to depleting your pack completely. Lithium ion chemistry also suffers from cold temperatures resulting in reduced performance, thus reducing your expected winter range.
We cannot rely on many real world range estimates because of the limited number of customer reviews. The sole reviewer awarded it 5 out of 5 stars, which is positive but statistically insignificant. Consider estimating your average daily range as 30 to 45 miles and compare it against your own experiences. For other options, browse the full battery comparison table or the battery roundup.
For Whom Is This Battery Designed?
It is time to state clearly for whom we believe this battery is suitable:
- Riders attempting to revive an older ebike with a battery that quit working mid-hill (this appears to be the prime candidate).
- Builders needing a tremendous amount of watt-hours of storage space for minimal dollars and are willing to manually align fitment.
- Anybody operating a motor ranging from 500W to 1500W and wanting to ensure they have sufficient reserve capacity for emergency situations.
Who should consider waiting:
- Anybody requiring an assured drop-in replacement with a previously proven mount, since this unit is a generic box and fitment is NOT guaranteed.
- Anybody seeking confidence that comes from knowing hundreds of customers reviewed it before spending money. Currently, Gofaro has only one Amazon review. While that fact isn't necessarily a red flag by itself, it certainly presents a warning signal. The earliest adopters typically identify problems.
Price Point
This sits at one of the lowest possible prices for a 20Ah pack, below what similar replacement packs cost from established manufacturers offering similar capacities.
While there is little doubt the Gofaro 48V 20Ah offers real capacity and value for its price, it is designed specifically for riders who desire their ebike operational again for pennies on the dollar, and aren't afraid to perform some minor adjustments themselves in regards to fitment. The capacity offered by this pack (912 to 960Wh) is substantial, the BMS's capability of supporting motors rated at 1500 watts provides a significant safety margin, and the price point per watt-hour is difficult to dispute.
To determine whether or not this is worth your investment, please check the latest Amazon pricing and customer comments before completing a purchase. Several additional reviews may have been added since this was published, which could provide valuable insight.
Frequently Asked Questions
How powerful of motors does this battery support?
According to the manufacturer, it supports motors rated up to 1500W. Based on the manufacturer's statement, we understand that a 1500W motor will require approximately 30 amps of current at full speed (possibly more). Thusly, we can infer that Gofaro believes their BMS has sufficient margin above peak motor current demand to prevent overheating and/or ignition.
What are the actual Ah ratings, 19Ah or 20Ah?
Both ratings are listed as capabilities by Gofaro. We calculate the actual storage capacity of this pack as approximately 912 to 960Wh. Consequently, regardless of whether or not you measure your real world range as either 912Wh or 960Wh, you'll receive a large-capacity pack providing considerable margin above your average daily range.
Will this battery fit my bike?
No guarantees are made by Gofaro as far as fitment goes. The description states that this battery will offer a universal or "other" form-factor. In layman's terms, that means it will be a generic replacement box instead of having a proprietary mounting configuration similar to those found on Hailong or Shark packs. Before ordering, measure your existing battery tray and verify that you have a compatible connector.
Can I safely connect it to my 1500W motor?
Based on specifications provided by Gofaro, theoretically yes. They list compatibility with 1500W motors, however we have concerns relating to potential failures of their BMS caused by excessive heat produced under continuous heavy loads. Budget packs like this include basic protections (e.g. overcharge protection, overdischarge protection, overcurrent protection, short circuit protection), but Gofaro doesn't publish any detailed information related to BMS specifications. Therefore, we advise extreme caution when connecting this pack to a motor rated at or exceeding 1500W and utilizing it aggressively.
Are any chargers supplied with this product and how long does charging take?
Unfortunately, we're unable to determine if any chargers are included with this product as we cannot locate that information within Gofaro's listing. If none are included, you'll need to source a compatible charger for your ebike with proper connectors/polarity along with wattage/amperage characteristics (minimum of 3 amps at 48V). Charging time will depend on charger amperage selection, although charging times will typically fall between approximately 5 to 8 hours at 2 amp/3 amp settings for a 20Ah pack.
Am I foolish for worrying about lack of reviews?
Yes, you'd be foolish not to recognize this as an issue. While it's great news that one person reviewed this product and awarded it five stars, that's just not enough evidence-based data points for us to confidently predict reliability over extended periods of usage.
What's my best option?
Your best option remains checking the Amazon page for Gofaro's product for updates on current pricing and recent customer comments before making your final decision.