Engineered for demanding portable electronics, this 3.7V 5000mAh cylindrical lithium-ion battery pack leverages premium 21700-format cells to deliver sustained, reliable power. The physical construction features a tightly wrapped, industrial-grade insulating PVC film that feels solid in hand, protecting the internal chemistry from environmental stressors and mechanical wear. By integrating an advanced Battery Management System (BMS) directly into the pack, along with pre-configured wiring and standardized terminals, this unit offers a plug-and-play power solution designed to accelerate your assembly lines.
With its compact cylindrical footprint and robust internal structure, the product achieves an optimal balance between volumetric energy density, extended cycle longevity, and rigorous safety protocols. It is specifically engineered to serve as the dependable core component for storytelling devices, precision power tools, and custom electronic assemblies requiring stable, long-lasting energy output.
Utilizing carefully sorted 21700 lithium-ion cells, this pack provides a substantial 5000mAh capacity. We implement automated capacity grading and internal resistance pairing, guaranteeing that large-volume procurement batches exhibit highly consistent discharge profiles, stable delivery timelines, and an exceptionally low defect rate.
The onboard industrial-grade Battery Management System (BMS) actively monitors voltage and thermal parameters. It delivers precise overcharge, over-discharge, overcurrent, and short-circuit protection, effectively neutralizing thermal runaway risks at the source to protect your brand's hardware reputation.
Constructed with high-temperature, flame-retardant silicone wiring and precision spot-welded nickel strips, the assembly minimizes internal resistance. Every unit undergoes rigorous 100% end-of-line testing. The exterior is sealed with a high-strength insulating sleeve, providing excellent tactile rigidity and resistance against mechanical shocks.
Engineered for barrier-free international market entry, this battery pack complies with stringent global standards, including CE, UL, UN38.3, and RoHS directives, ensuring that your end-products meet all regulatory and environmental requirements seamlessly.
Delivered fully assembled and debugged, the pack features standard connectors (e.g., XT60, JST). Our engineering team supports deep customization of BMS protection thresholds, wiring specifications, and physical pack structures to integrate flawlessly into your specific product housing without requiring secondary assembly.
Battery model: | 21700/3.7V/5000mAh |
Nominal voltage: | 3.6V |
Charging voltage: | 4.2V |
Charging current: | ≤2A |
Discharge current: | 2A |
Instant discharge current: | 5A |
Discharge cut-off voltage: | 2.75V |
Internal resistance of the finished product: | ≤150 mΩ |
Battery weight: | 120g |
Product dimensions: | 22*70mm (Maximum) |
Charging temperature: | 0～45°C |
Discharge temperature: | -20 to 60 °C |
Storage temperature: | -10 to 35 °C |
Battery casing: | None |
Lithium battery protection: | short-circuit protection, overcharge protection, over-discharge protection, overcurrent protection, temperature protection, and more. |
Application areas: | Storytelling devices |
This 3.7V 5000mAh power module is engineered to support a diverse array of electronics that demand a stable voltage platform, substantial energy reserves, and reliable discharge capabilities. Its versatile cylindrical form factor and customizable connection options make it a preferred choice for multiple demanding sectors:
Provides long-lasting, uninterrupted audio playback and interactive screen time, ensuring educational tools remain operational throughout extended learning sessions without the frustration of frequent recharging.
Delivers the necessary sustained current for small electric drills, precision screwdrivers, and hot glue guns, maintaining consistent torque and heating performance even under demanding mechanical loads.
Serves as a dependable energy reservoir for high-luminance LED flashlights, photographic fill lights, portable PA speakers, and remote monitoring hardware that require continuous, fade-free power delivery.
Ideal for custom DIY builds, lightweight drones, robotic assemblies, and electronic testing equipment, where an optimal power-to-weight ratio and a compact footprint are essential for structural integrity.
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Exclusively utilize constant voltage/constant current (CC/CV) chargers calibrated for a 4.2V output. Applying lead-acid chargers or non-compliant adapters will permanently damage the internal chemistry and void safety warranties.
Prevent exposure to extreme conditions. Do not puncture, crush, or submerge the cylindrical cell. Operating the unit outside the specified thermal window (above 60°C or below -20°C) accelerates degradation and compromises the structural integrity of the insulating wrap.
Verify that the host device's voltage requirements align perfectly with the pack's nominal output. Ensure strict adherence to correct polarity during installation; reversed connections will instantly trigger the protection circuit and may cause irreversible hardware damage.
When staging inventory for extended periods, maintain a state of charge between 30% and 60%. Store in a climate-controlled, dry environment away from conductive metal components to prevent accidental bridging of the terminals.
Our packaging complies strictly with IATA and UN38.3 dangerous goods regulations, utilizing professional-grade anti-shock insulation for safe global transit. Should any physical swelling, unusual odor, or rapid temperature spike occur during handling, immediately isolate the unit in a fire-safe, ventilated area.
A: Yes, it is fully compatible out of the box. The pack operates on a nominal 3.7V platform and features a highly stable discharge curve. This ensures consistent energy delivery, making it an optimal primary power source for storytelling machines, portable fans, and similar 3.7V electronics without requiring additional step-down converters.
A: Charging requires a dedicated lithium-ion balance charger outputting exactly 4.2V. When utilizing a standard 1A current, a full replenishment cycle takes approximately 5 to 6 hours. For faster turnarounds, a 2A charger reduces this time to roughly 2.5 to 3 hours. Never exceed the recommended 2A maximum charging current to preserve cell longevity.
A: Prolonged storage can cause natural self-discharge, prompting the onboard BMS to engage its deep-sleep over-discharge protection. To resolve this, apply a specialized lithium charger equipped with a low-current "wake-up" or pre-charge function. If the voltage does not recover, the unit requires professional assessment; do not attempt to bypass the protection board or disassemble the wrapping.
A: When maintained within the prescribed operational parameters—specifically avoiding deep discharges below 2.75V and overcharging—the internal 21700 cells will comfortably exceed 500 full charge-discharge cycles while retaining over 80% of their original 5000mAh capacity. Ambient temperature and discharge rates will influence the exact operational lifespan.
A: Absolutely. We offer comprehensive OEM/ODM services tailored to your structural engineering requirements. This includes modifying silicone wire gauges, adjusting cable lengths, and fitting specific terminal connectors (such as JST, XT30, or aviation plugs). We also accommodate custom BMS threshold configurations to ensure seamless integration into your final product assembly.
