Xtar VC4SL 4-Bay Battery Charger

Xtar VC4SL

The Xtar VC4SL is a four-bay USB-C battery charger designed to handle the full range of cylindrical lithium-ion and NiMH batteries, including the longer 20700 and 21700 cells that older four-bay chargers often struggle to fit. It connects via USB-C and supports QC3.0 input, which gives you a maximum charge current of 3A on a single slot or 2A across two slots simultaneously when you have the right power supply. Each bay is independent, so you can charge four different battery types or sizes at the same time.

The LCD screen shows the voltage, current, capacity and internal resistance of every battery as it charges. Beyond standard charging, the VC4SL has two additional modes: Storage Mode, which brings batteries to the optimal long-term storage voltage, and Grade Mode, which tests and records the real usable capacity of each cell. If you are using 18650, 21700 or 26650 cells in vape mods, torches, power tools or any other device, the VC4SL is one of the most capable and compact four-bay chargers available at its price point.

Xtar VC4SL Key Features

• 4 independent charging bays - charge different battery sizes and types 
• USB-C input with QC3.0 support – max 3A single slot / 2A per slot across two slots
• Charges Li-ion from 10440 up to protected 21700 and 26650 cells
• Charges NiMH/NiCd from AAAA to D size
• LCD display per slot: voltage, current, capacity (mAh) and internal resistance (mΩ)
• TC/CC/CV three-stage charging extends battery lifespan
• Storage Mode - discharges or charges to optimal storage voltage
• Grade Mode - full discharge and recharge cycle to measure actual usable capacity
• Can recover over-discharged Li-ion cells down to approximately 1.3V
• Auto battery type detection and reverse-polarity
• Flame-retardant ABS construction, 156 × 115 × 35mm

Charging Speeds

Charge current per slot is adjustable manually. The maximum speed achievable depends on how many slots are in use and the power supply connected. You need a QC3.0-rated power supply (5V/3A or 9V/2A) to reach the 2A and 3A speeds. A standard 5V/2.1A USB supply will still charge all four slots, but at the lower 0.5A or 1A rates only.

Compatible Batteries

The VC4SL charges the following battery types and sizes. All four outer and inner slots fit 21700 cells side by side, including most protected 21700s up to approximately 79.5mm in length. The two centre slots are narrower and will not accept 26650 cells - use the outer two slots for those.

Li-ion / IMR / INR / ICR (3.6V / 3.7V): 10440, 14500, 14650, 16340, 17335, 17500, 17670, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22650, 25500, 26650, 32650.

NiMH / NiCd (1.2V): AAAA, AAA, AA, A, SC, C, D.

The VC4SL does not charge 26800 cells (too long for the bays), LiFePO4 3.2V cells, or the newer proprietary single-ended Li-ion cells used in some specialist flashlights.

Display and Modes

The LCD above the charging slots shows four pieces of information per bay in real time: voltage (to the nearest 0.05V), charging current, cumulative capacity added in mAh since charging began, and internal resistance in milliohms. Internal resistance is a useful indicator of battery health - a cell with significantly higher internal resistance than others of the same type is degrading and worth flagging for replacement. The display stays lit while charging and dims after a short period of inactivity; pressing the Mode button wakes it.

The three modes are selected by pressing the Mode button when inserting a battery. Charge Mode is the default and handles standard CC/CV charging to 4.2V for Li-ion. Storage Mode will charge or discharge the battery to the optimal resting voltage for long-term storage - 3.7V for Li-ion and 1.2V for NiMH - which is useful if you are putting cells away for more than a few weeks.

Grade Mode performs a full discharge followed by a full charge cycle and records the actual usable capacity of the cell, which lets you compare real-world capacity against the rated capacity and identify cells that are no longer performing as expected.

Specifications

• Input: USB-C, QC3.0 (5V/3A or 9V/2A) or standard 5V/2.1A
• Li-ion charge cut-off: 4.2V ±0.05V
• Li-ion cut-off current: ≤120mA
• NiMH charge cut-off: 1.45V ±0.1V
• Max charge current: 4 × 0.5A / 4 × 1A / 2 × 2A / 1 × 3A
• Charging method: TC/CC/CV three-stage
• Dimensions: 156 × 115 × 35mm
• Construction: flame-retardant ABS

What's in the Box

• 1 x Xtar VC4SL charger
• 1 x USB-C cable
• User manual

Note: a QC3.0 wall adapter is required to achieve the 2A and 3A maximum charge speeds. Check your bundle - this may or may not be included depending on the variant stocked. A standard USB wall adapter will power all four slots at reduced speed.