Description
Efest SLIM K4 Type-C USB LED Battery Charger
Charge your rechargeable batteries faster and smarter with the Efest SLIM K4 Type-C USB Battery Charger. Designed for modern convenience, this intelligent 4-bay charger features a USB Type-C power input, automatic charging current adjustment, and advanced safety protections to provide dependable charging for a wide variety of lithium-ion batteries.
Whether you’re charging 18650, 20700, 21700, or other compatible battery sizes, the SLIM K4 delivers efficient performance in a compact, travel-friendly design backed by a three-year manufacturer warranty.
Note: Batteries are not included .
Intelligent 4-Bay Charging
The Efest SLIM K4 independently monitors each charging slot, automatically selecting the appropriate charging current based on the number and type of batteries installed.
Automatic Charging Modes:
1 × Battery: 1.0A
2 × Batteries: 2 × 1.0A
3 × Batteries: 3 × 0.5A
4 × Batteries: 4 × 0.5A
This intelligent charging system helps maximize battery performance while promoting long battery life.
Modern USB Type-C Power Input
Unlike traditional chargers, the SLIM K4 features a USB Type-C input , providing fast, reliable, and convenient power delivery.
USB-C Benefits:
Faster Charging Performance
Stable Power Delivery
Convenient USB Compatibility
Ideal for Home or Travel
Power the charger using compatible USB power adapters or other approved USB power sources.
Easy-to-Read LED Indicators
Built-in LED lights provide real-time charging updates, making battery management simple and convenient.
LED Features:
Charging Status Indicators
Easy Battery Monitoring
Automatic Charge Completion Display
Know exactly when your batteries are fully charged at a glance.
Advanced Safety Protection
The SLIM K4 is equipped with intelligent safety systems designed to protect both your batteries and charger during every charging cycle.
Safety Features:
Reverse Polarity Protection
Automatic Charge Completion
Overcharge Prevention
Intelligent Battery Monitoring
These protections help promote safe charging while extending battery lifespan.
Broad Battery Compatibility
The Efest SLIM K4 supports many of today’s most commonly used rechargeable lithium-ion battery sizes.
Compatible Battery Sizes:
10440
14500
16340
17340
18350
18490
18500
18650
20700
21700
26500
26650
Compatible with 3.6V and 3.7V lithium-ion batteries.
Technical Specifications
Input:
AC 100–240V, 50/60Hz
DC 5V / 2A
Output Voltage: 4.2V ±0.05V
Battery Cut-Off Voltage: 4.20V ±0.05V
Auto Recharge Voltage: 4.10V ±0.10V
USB Type-C Power Input
Four Independent Charging Bays
Compact & Travel-Friendly
The slim, lightweight design makes the SLIM K4 easy to carry while providing dependable charging performance at home, in the office, or on the go.
Why You’ll Love It:
Compact Design
USB Type-C Convenience
Intelligent Charging
Easy LED Monitoring
Reliable Everyday Performance
What’s Included
1 × Efest SLIM K4 LED Battery Charger
1 × USB Cable
1 × User Manual
1 × Warranty Card
1 × Scratch-Off Validation Serial Number
Battery Safety Guidelines
For safe charging and maximum battery life:
Never charge damaged batteries.
Inspect battery wraps before every charge.
Do not overcharge or over-discharge rechargeable batteries.
Always charge batteries on a clean, fire-resistant surface.
Never leave charging batteries unattended.
Store and transport batteries in protective, non-conductive battery cases.
Dispose of batteries according to local recycling regulations.
Why Choose the Efest SLIM K4?
Intelligent 4-Bay Charging
USB Type-C Power Input
Automatic Charging Current Selection
LED Charging Indicators
Reverse Polarity Protection
Automatic Charge Completion
Supports 18650, 20700 & 21700 Batteries
Compact, Travel-Friendly Design
Three-Year Manufacturer Warranty
The Efest SLIM K4 Type-C USB Battery Charger offers a modern, efficient charging solution for rechargeable lithium-ion batteries. With intelligent charging technology, broad battery compatibility, advanced safety protections, and convenient USB-C connectivity, it’s an excellent choice for users seeking dependable everyday battery charging.
