Top-down view of the SPERAS i4 4-slot smart battery charger featuring clear LED indicator bars
SPERAS i4 smart charger loaded with various Li-ion batteries charging independently, alongside its USB cable
Bottom view of the SPERAS i4 battery charger showing cooling vents for excellent heat dissipation and printed specifications
SPERAS i4 battery charger complete retail packaging and included accessories: charging unit, USB cable, and user manual

SPERAS i4 Charger 4 slot Charger 21700 Charger

$24.26
$24.26
Streamlined 4-Slot Power SPERAS i4 Smart LED 4-Slot Battery Charger Maximum reliability without the complexity. The SPERAS i4 is a rugged, highly efficient 4-bay charger featuring clear LED indicators, up to 2A fast charging in the fourth slot, and automatic intelligent charging modes (CC, CV, dv/dt) to keep all your Li-ion and Ni-MH batteries performing at their peak. i4 vs. D4S: Choose Your 4-Slot Charger Need 4 charging slots? Choose between the streamlined, rugged efficiency of the i4 or the premium display feedback of the D4S. Feature i4 (Streamlined Efficiency) 🔥 D4S (Premium Display) Display Type Clear LED Indicator Bars...
Please hurry! Only 99 left in stock
Subtotal: $24.26

Free Shipping

Free shipping on all order above $49.99 to most countries.

Warranty

Most flashlights can directly get 5 years warranty; battery and accessories get 1 year warranty.

Note

Any questions, please email to info@sperasflashlight.com

 
Top-down view of the SPERAS i4 4-slot smart battery charger featuring clear LED indicator bars

SPERAS i4 Charger 4 slot Charger 21700 Charger

$24.26

SPERAS i4 Charger 4 slot Charger 21700 Charger

$24.26
Streamlined 4-Slot Power

SPERAS i4 Smart LED 4-Slot Battery Charger

Maximum reliability without the complexity. The SPERAS i4 is a rugged, highly efficient 4-bay charger featuring clear LED indicators, up to 2A fast charging in the fourth slot, and automatic intelligent charging modes (CC, CV, dv/dt) to keep all your Li-ion and Ni-MH batteries performing at their peak.

SPERAS i4 4-slot battery charger loaded with various Li-ion batteries including 21700 and 18650, alongside a USB-C cable

i4 vs. D4S: Choose Your 4-Slot Charger

Need 4 charging slots? Choose between the streamlined, rugged efficiency of the i4 or the premium display feedback of the D4S.

Feature i4 (Streamlined Efficiency) 🔥 D4S (Premium Display)
Display Type Clear LED Indicator Bars High-Definition LCD Screen
Charging Slots 4 Independent Slots 4 Independent Slots
2A Fast Charging Dedicated 4th Slot Auto-Selected by Charger
Best For Rugged, simple, cost-effective charging Users who want exact voltage/data readouts

Core Professional Features

Independent Control & 2A Fast Charge

The i4 controls each of its 4 slots completely independently. It is widely compatible with Li-ion and Ni-MH/Ni-Cd batteries (including 21700, 26650, and 18650). Need power fast? The dedicated fourth slot provides up to 2A rapid charging speed to get your high-capacity cells ready in record time.

Top angle view of the SPERAS i4 LED charger powering multiple battery chemistries and sizes independently

Smart Modes & Ultimate Safety

Behind the simple LED interface is a highly intelligent core. The i4 automatically selects between 3 charging modes (CC, CV, or dv/dt) for optimal battery health. The chassis features an excellent heat dissipation design with built-in cooling vents, paired with robust reverse polarity and short circuit protection.

Bottom view of the SPERAS i4 battery charger showing cooling vents for heat dissipation and the detailed technical specifications label

Over-Discharged Battery Activation

Don't throw away "dead" batteries just yet. The SPERAS i4 features an advanced Li-ion battery restoration function that can safely activate and revive over-discharged cells. Combined with automatic termination upon charging completion, it ensures your batteries are both recovered and protected from overcharging.

Technical Specifications

  • USB Input: 5V/2A
  • DC Output: DC 4.2V / 1A * 2 OR 2A * 1 OR 0.5A * 4
  • Compatible Batteries: 21700, 26650, 18650, 16340, 14500 Li-Ion, Ni-MH/Ni-Cd, etc.
  • Dimensions: 110mm (L) * 48.4mm (W) * 28.9mm (H)
  • Weight: 107.2g (net weight) / 146g (gross weight)

📦 What’s in the Box

  • 1 × SPERAS i4 Battery Charger
  • 1 × Charging Cable
  • 1 × Carrying Pouch
  • 1 × User Manual
SPERAS i4 battery charger retail packaging and contents including the unit, wrapped USB-C cable, and user manual

Frequently Asked Questions

What is the main difference between the i4 and the D4S?

The SPERAS i4 is a streamlined, highly reliable model that uses simple LED indicator bars to show charging progress. The D4S is the premium version that features a full LCD screen for exact digital readouts. Both safely charge 4 batteries independently.

Which slot should I use for 2A fast charging?

On the SPERAS i4, the fourth slot (far right) is specifically designed to provide up to 2A of rapid charging current. We recommend placing your highest-capacity batteries (like a 21700 or 26650) in this slot when you need them charged as quickly as possible.

What do the CC, CV, and dv/dt charging modes mean?

These are automatic smart charging phases designed to protect your battery. The i4 uses CC (Constant Current) to charge quickly when the battery is low, switches to CV (Constant Voltage) to safely top it off, and uses dv/dt (Delta Voltage) termination for Ni-MH batteries to prevent overcharging.

Enlarged view of SPERAS i4 charger

Related Products

Recently Viewed Products