The DC 8.4V 1A power supply adapter is designed to safely charge 7.4V-8.4V 18650 Li-ion batteries with precision voltage control, thermal protection, and automatic shutoff. It delivers 1 amp of current to balance speed and battery longevity, making it compatible with devices like flashlights, drones, and portable power tools that use dual-cell lithium-ion configurations.
How Does the JK Active Balancer Optimize Battery Performance?
How Does the Adapter Ensure Safe Charging for Li-ion Batteries?
The adapter integrates over-voltage protection, short-circuit prevention, and temperature monitoring to avoid overcharging. Its 8.4V output matches the full charge voltage of two 18650 cells in series, while the 1A current adheres to standard charging rates for these batteries. Reverse polarity protection safeguards against incorrect connections.
Advanced charging algorithms use three-stage regulation: bulk charging at constant current, absorption phase with voltage stabilization, and final float mode. The microcontroller samples battery voltage 10 times per second through separate sensing wires in the DC connector. During testing, the adapter successfully terminated charging within 15mV of target voltage across 500 consecutive cycles. For environments with unstable power inputs, built-in voltage clamping diodes protect against line surges up to 6kV.
What Are the Key Technical Specifications of This Charger?
Input: 100-240V AC (50/60Hz); Output: 8.4V DC at 1A. The 2.1mm x 5.5mm DC plug supports most 18650 battery packs. Efficiency exceeds 80% with less than 0.3V ripple noise. Operating temperature: 0°C to 40°C. Safety certifications include CE, FCC, and RoHS compliance.
How Does the Daly Smart BMS Enhance Battery Management Systems?
| Parameter | Specification |
|---|---|
| Output Accuracy | ±1% voltage, ±5% current |
| Ripple & Noise | <150mV p-p |
| Protection Response | <500ms for faults |
Can This Charger Prolong 18650 Battery Lifespan?
Yes. The 1A current (0.5C rate for 2000mAh cells) prevents stress from fast charging. Automatic trickle charging activates below 3V/cell to recover over-discharged batteries safely. Charge termination at 8.4V±0.05V avoids capacity degradation from overcharging, preserving up to 80% capacity after 500 cycles.
Laboratory aging tests show cells charged with this adapter retain 92% capacity after 200 cycles compared to 78% with generic 2A chargers. The adaptive pulse charging method reduces lithium deposition on anode surfaces by 40% compared to continuous current. Users report 18-24 month typical battery service life extension when charging nightly, with measurable capacity retention improvements visible after just 3 months of regular use.
“This adapter’s CC/CV charging profile aligns perfectly with 18650 requirements. The inclusion of a Schmidt trigger comparator for charge termination adds military-grade reliability missing in generic chargers. For DIY enthusiasts, it’s a safe alternative to modifying ATX power supplies for lithium packs.”
— Senior Power Systems Engineer, Battery Tech Innovations
FAQ
- Can I charge single 18650 cells with this adapter?
- No. The 8.4V output exceeds single-cell voltage limits (4.2V max). Use only with 2S battery packs.
- Does it work with 20700 or 21700 batteries?
- Yes, if arranged in 7.4V-8.4V configurations. The charger cares about voltage, not physical cell size.
- How long does a full charge take?
- For dual 3000mAh 18650s: (2 x 3000mAh) / 1000mA = 6 hours from empty. Actual time varies with initial charge level.