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Product Description:
The BAK 21700 50D is a next-generation high-drain lithium-ion battery engineered with advanced tabless technology. This 2pcs bundle delivers a massive 5000mAh capacity, an ultra-low internal resistance of just 4mΩ, and a wide operating temperature range from -40°C to 60°C. It sets a new standard for 21700 performance, providing explosive power and exceptional reliability even in extreme cold environments.
Unlike traditional cells that use threaded or spiral-welded negative terminals, the BAK 50D features a unique spot-welded negative terminal design. This advanced manufacturing process contributes to its ultra-low resistance and superior performance. With its wide temperature range, it is the ultimate power source for high-power devices, cold-weather flashlights, electric tools, and outdoor equipment.
Key Features:
BAK 21700 50D Premium Cell: Next-generation high-drain Li-ion battery with advanced tabless technology.
5000mAh High Capacity: Provides massive energy for extended runtimes.
Ultra-Low Internal Resistance (4mΩ): Ensures minimal heat generation and maximum power transfer efficiency.
Wide Operating Temperature (-40°C to 60°C): Delivers reliable performance in extreme cold and hot environments, perfect for northern winters.
Advanced Tabless Technology: Newer tabless design offers lower internal resistance and better performance compared to traditional spiral-welded cells.
Unique Spot-Welded Negative Terminal: Features a spot-welded imprint at the negative terminal, a distinct mark of its advanced manufacturing process.
Standard 21700 Size: Perfectly fits standard 21700 battery compartments (21mm x 70mm).
Versatile Applications: Ideal for high-power flashlights, electric tools, drones, and outdoor gear.
Product Parameters:
Brand: BAK
Model: 50D
Size: 21700
Capacity: 5000mAh
Nominal Voltage: 3.7V
Full Charge Voltage: 4.2V
Internal Resistance: Approx. 4mΩ (Tested at low temperature)
Chemistry: Li-ion (Lithium Ion)
Operating Temperature: -40°C to 60°C
Negative Terminal: Spot-welded imprint (Non-threaded/Non-spiral)
Dimensions: 21mm (Diameter) x 70mm (Height)
Pack Quantity: 2pcs
Applications:
High-Power Tactical Flashlights: Powers the brightest flashlights and searchlights with extreme 4mΩ low internal resistance.
Cold-Weather Outdoor Gear: Ideal for outdoor equipment and power tools used in extreme cold environments.
High-Performance Drones & RC Hobbies: Provides sustained high-current power for heavy-lift drones and RC vehicles.
Cordless Power Tools: Delivers high-power output for demanding power tools and electric drills.
Professional Industrial Equipment: Reliable power for industrial applications requiring high discharge and wide temperature tolerance.
Frequently Asked Questions (FAQ):
Q1: What is the advantage of tabless technology?
A1: Tabless technology eliminates the traditional spiral or threaded connections, resulting in significantly lower internal resistance. For the BAK 50D, this translates to an ultra-low 4mΩ IR, which means less heat generation and more power delivered to your device.
Q2: What is the operating temperature range of this battery?
A2: The BAK 50D has an impressive operating temperature range of -40°C to 60°C. This makes it the ideal choice for devices used in extreme cold environments, such as northern winters or high-altitude operations.
Q3: Is the 5000mAh capacity real?
A3: Yes. The BAK 50D delivers a true 5000mAh capacity, providing reliable, long-lasting energy for high-drain devices.
Q4: How does the negative terminal differ from traditional batteries?
A4: Unlike traditional batteries that use threaded or spiral-welded negative terminals, the BAK 50D features a spot-welded imprint at the negative terminal. This advanced manufacturing technique is a hallmark of its superior engineering.
Q5: What kind of charger should I use for this battery?
A5: You must use a charger specifically designed for 3.6V/3.7V Li-ion batteries with a 4.2V cut-off voltage. Do not use a standard AA/AAA Ni-MH charger.
Free Shipping: Enjoy free shipping on all orders over $65. For orders under $65, the shipping cost is $8.99.
Delivery Time: Once shipped, orders typically arrive within 7–15 business days.
Easy Returns: We want you to be completely satisfied. If you're not, you can return your product within 30 days of receiving your order. Please ensure the items are unused and in their original condition. For return instructions, please contact our support team.
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The BAK 50D is now my go-to 21700 cell. Highly recommended.
They outperform every other cell I own in freezing conditions.
I replaced my old cells with these. My unicycle has noticeably more power when climbing hills.
My laser level needs high peak current. These cells provide it without any flickering.
These feel like industrial-grade cells. The build quality is excellent.
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