Silver fish style battery is the most common type of battery used in the budget e-bike market. Your bike most likely utilizes this same format if it has a battery that tucks in back of the seat tube. This is commonly referred to as a "shark" battery. The LZIXYM 48V 13Ah silver fish ebike battery contains 624 Wh in a 9 pound package, and comes equipped with a 25 amp BMS (Battery Management System), along with several convenience items that many packs within this price range completely omit.
This is a great replacement option for the numerous 48 V bikes utilizing the silver fish housing, and as it is a new listing, you get to purchase it close to the beginning of sales cycle versus competing for a long-established product.
The silver fish shape is important to understand prior to making a purchase, as it is not a universal battery. The battery attaches to the seat tube via a bracket, and the discharge connector must match that of your bicycle. Replacing an older silver fish battery generally represents a direct swap taking approximately 10 minutes. When purchasing a brand new silver fish battery, take accurate measurements and verify the connector prior to installation. A battery with correct voltage but incorrect size is essentially worthless regardless of how good the internal cells are.
Specs & Build Quality
The numbers on this one are clear-cut. 48 Volts times 13 Amp Hours equals 624 Watt Hours of stored energy. This is a medium level capacity for a 48 Volt battery and ample storage for a daily commute or extended afternoon rides. The LZIXYM 48V 13Ah weighs in at 9.0 pounds and measures 15.35 x 2.95 x 4.37 inches (390mm x 75mm x 111mm). These are average weights for a pack of this size. While not lightweight, it is not overly heavy either.
Build quality matches what you would expect from a budget pack. The case consists of a rugged plastic shell that fits snugly against the seat tube. The manufacturer (Dongguan Yizhan) specifies the pack supports motors ranging from 0 to 750 Watts, which accounts for nearly every ebike currently available. The included top-mounted carrying handle provides an excellent feature. It gives you a sturdy object to grasp when removing/replacing the pack for charging, etc., and adds a sense of design thoughtfulness as though they have actually carried one themselves.
BMS, Safety, & Design Features
The standout item is the included 25 Amp BMS. For a pack of this size, it offers sufficient room (about 1200 W) above the rated motor capacity (750 W). All standard protections (overcharge, over-discharge, temperature protection) are integrated directly into the pack itself. Temperature protection is especially valuable as it prevents the pack from overheating (and thus failing) if left unattended during use.
In addition to the above mentioned safety features, this pack includes a locking mechanism that can be secured using the provided keys. Although no lock will ever prevent a determined thief from breaking into your bike using tools, this locking mechanism will at least deter those thieves looking to quickly steal your bike and flee the scene.
Lastly, there is a bright LED indicator located on the top of the pack that displays remaining charge at a glance. This eliminates guesswork regarding whether or not you still have sufficient power to get home in time.
There is one significant caveat to consider and this relates to the position of the four-pin discharge connector on this particular model. Rather than being positioned on top of the pack as found on most silver fish-style batteries, it is located on the underside. In general, each bike manufacturer positions their discharge connectors in a specific area and if your bike requires the connector to be installed on top (as opposed to underneath) you will not be able to easily connect them.
Therefore, we recommend checking where your current discharge connector resides on your bike prior to ordering this pack. In most cases, you can replace your current battery with minimal hassle (in under five minutes) assuming both dimensions and connector locations align.
What Amazon Reviewers Are Saying About the Pack
As of today's writing date (August 2026), this is a relatively new listing, therefore very little has been said about this pack by reviewers. To date, there are only two Amazon reviewers who have purchased and reviewed this pack. Both reviewers have given this pack a perfect five-star rating. However, keep in mind that two reviews does not represent enough data to draw conclusions regarding long-term performance and durability issues related to the placement of the four-pin connector on the bottom of the pack. However, these two initial purchases demonstrate satisfaction with their respective purchases based solely upon the product specs and marketing claims made by the vendor. Therefore, based upon limited reviewer feedback alone, you may safely assume this pack meets expectations based upon specifications alone and should be tested heavily immediately after receipt of shipment.
While we believe it is reasonable to bet on this budget-pack meeting your needs, testing this pack thoroughly (charging, discharging, verifying connection points, etc.) as soon as possible after receiving your shipment is essential to ensure optimal longevity and overall value.
Range & Real-World Performance
Assuming you're operating at moderate levels (typically around 250 W to 500 W with considerable pedaling assistance), you can anticipate somewhere in the range of 25 to 40 miles from your daily commutes with a 13 Ah battery supplying 48 Volts (624 Wh). Should you push harder (hammering a 750 W motor with excessive throttle), mileage will decrease significantly depending on terrain, rider weight, wind resistance factors and other variables, and we estimate between 15 to 25 miles per charge.
These estimates reflect normal physical limitations associated with the 624 Wh capacity tier. There isn't another battery within this class capable of transforming a 750 W motor into an all-day cruiser covering distances exceeding sixty miles.
For commuters completing round-trip commutes typically falling within the range of 10-15 miles in length, the provided 624 Wh supplies an adequate margin of comfort, even allowing for additional travel between charges if not aggressively throttling throughout your ride. Additionally, the intelligent LED indicator supplied allows you to determine remaining charge at-a-glance, eliminating uncertainty when trying to gauge if you'll arrive home with sufficient charge when running behind schedule. Click Here to View Current Pricing & Latest Reviews on Amazon, or compare this pack against other choices in our eBike Battery Comparison Table, and browse through other battery reviews on our Blog.
Frequently Asked Questions
Will this replace my existing silverfish housing?
Verify your original dimensions compared to our specified dimension(s): 15.35 x 2.95 x 4.37 inches. Also verify that your present discharge connector location corresponds to the connector location depicted on this page (located at the bottom).
Is the LZIXYM 48V 13Ah rated for all motors?
Yes. According to LZIXYM specifications, this pack can support motors with ratings from 0-750 watts.
How long until I start losing range due to degradation?
Expect anywhere from hundreds to thousands of cycles prior to experiencing measurable losses in range depending on how you utilize and maintain your pack.
Does the LZIXYM 48V 13Ah include a charger?
No. A charger is NOT included in the box contents. The package includes the battery, holder, user manual, and two keys. If you need a charger, confirm the current listing before you order.
Is the battery waterproof?
Like most budget ebike batteries, the housing will shrug off light rain, but it is not designed for submersion. Keep it out of deep puddles and do not hose it down, and the pack should be fine for everyday riding in the elements.
What is the warranty?
The battery carries a one year warranty from manufacturer Dongguan Yizhan. That is standard for the budget segment, so read the listing for the exact terms before you rely on it.