The silver fish 48V 15.6Ah by SDTYYP ebike battery contains 749 wh of usable energy in an IP68-rated aluminum alloy case with a key lock (for secure attachment), a transport handle, a power display and a lifespan rating of 800 cycles. A silverfish battery at this price point does not normally have all these features. Most low-cost ebike batteries sacrifice either weather sealing, or security, or longevity. SDTYYP did not. In addition to the features mentioned, the listing indicates there are both 25 amp and 30 amp BMS available, and they provide enough headroom for a motor rated anywhere from 250 W to 1000 W. See the comparison table we have created for other 48 V packs at this link.
Specs and Build Quality
The SDTYYP silver fish 48V 15.6Ah is built using the silver fish format, which is designed for mounting behind the seat tube of several types of commuter and folding bikes. Instead of plastic enclosures common on less expensive ebike battery packs, this enclosure is made from aluminum alloy. Aluminum allows for better thermal conduction than plastic which will help keep the cells cooler during extended loads. Additionally, the aluminum casing provides a very solid feel when sliding the pack into the cradle.
With a total of 48 volts and 15.6 amp hours of total capacity, the calculations result in 749 wh of usable energy. While not as high as some larger shark-style batteries or rear rack mounted packs, it's sufficient for daily commuting with ample reserve. There is a power display located on the enclosure to allow you to easily view the amount of energy left in the pack. The enclosure also has LED light displays to show you the approximate charge level quickly.
As stated earlier, since this is a silver fish format battery and it mounts via a seat post-mounted cradle, swapping it in should be a simple process if your previous battery also utilizes a similar cradle type. The key lock serves multiple purposes here as well. Not only does it prevent someone from lifting the pack off the bike, but it also functions as an immobilizer to ensure the pack will not turn on when locked to the bike. Additionally, there is a handle on top of the pack for easy carrying when you decide to remove it from the bike.
BMS, Safety, and Design Features
According to the listing information, this silver fish 48V 15.6Ah battery comes equipped with a 25 A or 30 A BMS. Since this is a 48 V battery, a 30 A BMS will supply approximately 1440 W of instantaneous maximum output (which covers almost all 1000 W motors). The 25 A BMS will still cover most 750 W builds. As with all lithium-ion based battery packs, the BMS prevents overcharging, over-discharging, excessive current flow and short-circuits.
I think one of the most interesting items listed about this pack was the cycle-life figure of 800. While I believe you should take such claims from manufacturers of low-priced packs with some caution, having a stated cycle-life figure is a good thing. It at least lets us know the manufacturer expects it to last. If you use your pack once per day, that would equate to two to three years before you'd start seeing a decline in range due to degradation.
Finally, according to the listing, the SDTYYP silver fish 48V 15.6Ah has an IP68 rating. An IP68 rating means that the shell is totally dust-proof and capable of being continuously submerged underwater. While I don't suggest submerging this or any ebike battery in water for fun, this should protect against any rain, flooding, and similar events that may occur.
All indications are that this pack has been built with care, and with some consideration given to providing useful functionality.
Who Is This Battery For?
Well, that's the question isn't it. Here's my answer: I have serious reservations recommending anything until I see customer reviews. Customer reviews are basically the only way to validate any claims regarding performance, reliability and durability of products like ebike batteries. So why am I reviewing this now? Well, the specs look great for the price. The aluminum shell looks durable. The key lock appears to be useful. The portable handle is convenient. And I've never seen an 800-cycle claim from a manufacturer before.
Additionally, SDTYYP produces this battery in various configurations including 36 V and 48 V systems, and in 15.6Ah, 18Ah and 21Ah capacities. This tells me that SDTYYP is producing a series of related products and not just trying something new.
However, there are no reviews for this product yet. Therefore, you need to test it thoroughly once it arrives to verify everything works as advertised (fitting correctly, charging fully, discharging properly, retaining expected range). Once you're sure it meets your expectations, then it might be worth considering purchasing.
Based upon specifications alone, I'd say this battery would be suitable for riders whose ebikes run on a 48V system and utilize a motor rated anywhere from 250W through 1000W who desire a silverfish battery that is weather-sealed, keyed to their bike securely and has adequate range. It could also be considered by commuters who ride in bad weather or otherwise desire the assurance provided by an IP68-rated shell. Finally, if you have a worn-out old battery and want to upgrade to a silverfish configuration with greater capacity in the same footprint as your existing battery, then perhaps this is a viable solution. For more on how batteries compare across voltages and formats, check our blog.
Frequently Asked Questions
Which motors can this ebike battery operate?
The SDTYYP listing says this battery supports operation of motors ranging in size from 250 W to 1000 W. Both versions (the 25 amp and the 30 amp) offer sufficient headroom for both sizes.
What is the usable capacity of this ebike battery?
The usable capacity of this battery is calculated at approximately 748 wh (using a nominal voltage of 48 volts and a total capacity of 15.6 Ah). SDTYYP also lists additional capacities (18 Ah and 21 Ah) and voltages (36 V) to meet different user requirements.
Is this ebike battery waterproof?
Yes, this battery is waterproof, as indicated by its IP68 rating. According to SDTYYP's documentation, this means that it is completely sealed from dust and can withstand continuous exposure to water.
How long will this ebike battery last?
The manufacturer states that their silver fish battery will retain greater than 80% of its original capacity after 800 complete discharge/recharge cycles. Assuming one charge/discharge cycle per day (a reasonable assumption for most users), this would translate to two to three years of usage before you would experience significant reductions in operating range due to cell degradation.
Will this battery attach securely to my ebike?
Yes, according to the manufacturer's documentation, this pack attaches securely to your bike via a seatpost mounted cradle and includes an immobilizer which ensures that your pack cannot be started while it is attached to your bike via key-lock.
Can I install this battery on my ebike?
If you currently have an ebike battery utilizing a similar cradle design (silver fish format) then yes, installation should be relatively simple. However, please review your connector type and cradle design before placing an order to confirm compatibility.