UNITPACKPOWER Pro-Series 21700 Polly Downtube Battery Line.
UNITPACKPOWER Pro-Series 21700 Polly Downtube Battery Line.
UNITPACKPOWER Pro-Series 21700 Polly Downtube E-Bike Battery (36V / 48V / 52V / 60V / 72V)
Unleash the ultimate range, raw speed, and torque potential of your electric bicycle with the UNITPACKPOWER Pro-Series 21700 Polly Downtube Battery Line. Engineered as a rugged, frame-mounted solution for high-demand riders, this premium tier is meticulously built using genuine, name-brand LG 4800A and Samsung 50E 3C high-discharge 21700 cells.
From reliable 36V street commuters to heavy-duty 48V/52V mid-drives, and massive 60V/72V off-road velocity builds, this smart power pack is designed to power high-wattage motor setups up to 2000W without broken connections or premature voltage drop.
🚀 Key High-Performance Features
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Authentic LG & Samsung 21700 Cells: Configured with ultra-dense premium cells (LG 4800A / Samsung 50E) that provide massive amp-hour capacities in a compact footprint while offering unmatched thermal stability under load.
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Massive 1,000+ Deep Cycle Lifespan: Engineered for high mileage and longevity. These grade-A branded cells are built to retain strong capacity holds through over 1,000 full charge-discharge cycles.
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Universal High-Wattage Motor Support: Built to comfortably supply steady continuous current to hub wheels and mid-drive motor kits ranging from 250W, 500W, 750W, 1000W, 1500W, up to 2000W.
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Ergonomic Polly Frame Housing: Encased in a sleek, impact-resistant downtube shell that mounts cleanly to your water bottle boss holes. Features an integrated power switch, a real-time battery gauge, and a heavy-duty key lock.
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Extended 18-Month Warranty Plan: Your investment is protected by a comprehensive 18-month factory warranty against manufacturing and structural defects.
🛡️ Safety Certifications & Quality Guarantees
The 48V 52V Polly E-bike Battery Pack is built with strict internal grid spacers to cushion cells against intense trail vibrations.
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Global Compliance Standards: Fully CE and RoHS certified. Manufactured with structural integrity, containing zero chemicals of high safety concern (
High-concerned chemical: None). -
Intelligent Protective Smart BMS: Outfitted with an advanced Battery Management System tailored to your voltage tier to prevent over-charging, deep discharge, over-current, and short-circuits.
📊 System Customization Options & Sizing Matrix
Please pick your matching system voltage and target capacity block to match your motor and controller requirements:
| Nominal Voltage | Available Capacity Configuration Layouts | Recommended Motor Range | Included Charging Unit |
| 36V Systems | 15Ah / 19.2Ah / 24Ah / 25Ah / 33.6Ah / 35Ah | 250W - 750W Motor | 42V 2A/3A Smart Charger |
| 48V Systems | 14.4Ah / 15Ah / 19.2Ah / 20Ah / 24Ah / 25Ah | 500W - 1500W Motor | 54.6V 2A/3A Smart Charger |
| 52V Systems | 14.4Ah / 15Ah / 19.2Ah / 20Ah / 24Ah / 25Ah | 750W - 1500W+ Motor | 58.8V 2A/3A Smart Charger |
| 60V Systems | 15Ah / 19.2Ah / 20Ah / 24Ah / 25Ah | 1000W - 2000W Setup | 67.2V 2A/3A Smart Charger |
| 72V Systems | 15Ah / 19.2Ah / 20Ah / 24Ah / 25Ah | 1500W - 2000W Peak | 84V 2A/3A Smart Charger |
📦 What's Included in the Box?
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1 x UNITPACKPOWER Pro-Series Polly Downtube Lithium Battery Pack
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1 x Rigid Frame Mounting Docking Cradle Plate with Key Lock Infrastructure
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1 x High-Efficiency 2A or 3A Smart Charger (Configured to your selection)
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2 x Anti-Theft Protection Keys
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1 x Comprehensive User Installation Manual
Take your electric bike or high-speed scooter build to its absolute peak limits. Choose your exact voltage, capacity, and cell variant configuration below, and click Add to Cart to buy your UNITPACKPOWER pack today!
Why Choose the UnitPackPower (UPP) Official Store?
When you buy a high-capacity lithium battery, you aren’t just buying range—you are investing in safety, cell reliability, and long-term performance. Here is why tens of thousands of electric bike and scooter builders trust UnitPackPower (UPP) Official over cheap, generic alternatives:
🏭 1. Factory-Direct Freshness & Deep Customization
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Zero Stale Inventory: Every battery pack we ship is either brand new, directly from the assembly floor, or maintained within a strict 3-month rotation window in our local overseas distribution warehouses.
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Complete System Versatility: We stock the industry’s most comprehensive matrix of power profiles, including 24V, 36V, 48V, 52V, 60V, and 72V form factors.
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Custom Build Infrastructure: Need a tailored fit? We fully support custom engineering requests for unique voltages, capacities, BMS current limits, and specific case sizes to slide perfectly into your custom build.
🛡️ 2. Uncompromising Quality Control: No Fakes, No Traps
We refuse to play the race-to-the-bottom game by using recycled, unbranded, or B-grade cell packs just to flash a low price. Our manufacturing philosophy is simple: No Fakes. No Cheap Substitutes. No Traps.
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Genuine Grade-A Cells Only: Every pack utilizes verified, official-source cells (including Samsung, LG, Panasonic, and top-tier Grade-A manufacturers).
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Multi-Protection Smart BMS: Every battery is managed by an advanced BMS balancing circuit to guard against thermal overruns, short circuits, and over-discharging.
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Fused CE Smart Chargers: Our included chargers feature inline structural safety fuses to prevent grid surges from reaching your battery.
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Certified Peace of Mind: Fully certified and legally backed by strict global regulatory benchmarks, including CE, UL, and RoHS compliance reports, alongside legal MSDS and UN38.3 shipping safety documentation.
🔧 3. True Global After-Sales & 18-Month Warranty Support
We stand behind our craftsmanship long after your package arrives. If you run into any issues on the road, you are backed by real, local human support:
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18-Month Factory Warranty: Comprehensive coverage against operational and material defects.
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Localized Assistance Hubs: Dedicated, hands-on support infrastructure across the USA, Canada, Germany, Belgium, the UK, Poland, and Australia.
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Hassle-Free Protection: Access to free returns, complete physical repair support, drop-in structural replacement parts, and direct video technical walkthroughs from our core engineering crew.
⚠️ Important Global Shipping Notices Before Ordering
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🇺🇸 United States (Hawaii & Alaska): Shipments traveling to Hawaii and Alaska require localized regional airfreight adjustments. Please contact our support team to verify shipping coordinates before finalizing your transaction.
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🇪🇸 Spain (Islands): Our standard mainland transport logistics cannot fulfill orders to Spanish island addresses carrying zip codes that begin with 35 or 38.
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🇰🇷 South Korea: To ensure swift, customs-cleared processing at port entries, all South Korean orders must include a valid Personal Customs Clearance (PCC) code within the order notes.
21700 Lithium Cell Polly Ebike Battery Specifications
Charger Plugs and Discharge Connectors Optional
1. Charger Plug: US, EU, UK, AU plugs are optional, will be provided according to the delivery country if not requested.
2. Discharge Connector: There are 7 kinds of optional connectors as shown in the picture below, which will be soldered with the default female connector and extra male connector if not requested.
3. If you have any requirements about this, please leave a message in your order.
Guarantee
1) We provide an 18-month warranty for all electric bike batteries.
2) If there is a quality problem with any battery within one month, we can resend you a new one after providing your proof.
3) Any battery with a quality problem within one year, we provide free repair.
4) All our electric bicycle batteries have high-quality cells and BMS, and they will be 100% tested before shipping.
Top brand lithium battery manufacturer in China, rest assured to buy.
We don't supply warranty service for the following situations:
1) The battery goes over the water.
2) The battery is broken by man-made.
3) The cells are burnt out after incorrect use.
4) Return the battery without a reason.
5) Open a dispute without contacting us.
Feedback
1) Our battery can fit most of the motor kits, excluding (not only) these: B0SCH, SHIMANO, YAMAHA, Panasonic.
2) Please contact us if you can't confirm whether our battery can fit your motor.
3) If you have any problems, please feel free to contact us BEFORE you leave negative feedback or file a dispute.
4) Any problem is not a problem, as long as you contact us.
5) Your satisfaction and positive feedback are very important to us.
6) Please kindly leave us positive feedback and 5 Stars if you are satisfied with our items and services.
Details
This product is crafted with quality materials to ensure durability and performance. Designed with your convenience in mind, it seamlessly fits into your everyday life.
Shipping & Returns
We strive to process and ship all orders in a timely manner, working diligently to ensure that your items are on their way to you as soon as possible.
We are committed to ensuring a positive shopping experience for all our customers. If for any reason you wish to return an item, we invite you to reach out to our team for assistance, and we will evaluate every return request with care and consideration.
