Swanlake 18650 Battery Charger AA AAA Fast Charger for 3.7V Lithium
Quick take
The Swanlake single-slot charger is built for mixed households and tools, with support for 3.7V lithium-ion cells (including common 18650 and 21700 sizes) plus 1.2V Ni-MH/Ni-Cd AA/AAA-style cells. It runs from USB power, offers selectable charging current, and shows a simple capacity indicator. The main thing to double-check is battery compatibility and the charger’s single-bay design if you need to charge multiple cells at once.
Pros and cons
Pros
- Universal support for both 3.7V lithium-ion cells and 1.2V Ni-MH/Ni-Cd AA/AAA-type cells
- USB charging input (useful for laptop, computer, car charger, or other USB power)
- Selectable current modes (0.5A, 1A, 2A) and an LCD-style capacity indicator (25%, 50%, 75%, 100%)
- Auto power-off when fully charged, plus built-in protection (short circuit, overheat, over-voltage)
Cons
- Single-slot design, so charging multiple batteries means doing it one at a time
- Capacity indicator is percentage-based, not a detailed readout for voltage or charge rate
What buyers think
Buyer-review evidence is strongly positive on basic usability and convenience. Multiple comments highlight the compact size (helpful for storage), the indicator lights being easy to read, and straightforward battery insertion into the charging slot. Overall feedback also emphasizes that it works across a range of battery sizes the charger is meant to accept, and that the percent-based charge display is a practical feature.
What this charger is, and who it’s for
This is a USB-powered, single-bay charger designed to cover two common “battery worlds” in one device: 3.7V lithium-ion rechargeable cells (like 18650 and 21700 families) and 1.2V Ni-MH/Ni-Cd rechargeable cells in AA/AAA-style sizes. If you manage batteries for flashlights, small tools, vaping devices, or other electronics that use different chemistries, having one charger that can handle multiple types can simplify your setup.
Key features that matter in everyday use
Compatibility across multiple battery sizes and chemistries
On the 3.7V side, it targets lithium-ion rechargeable cells in sizes such as 18650, 18500, 18350, 17650/17670/17500 families, 16340, 20700, 21700, and 26650, among others listed. On the 1.2V side, it’s intended for Ni-MH/Ni-Cd AA/AAA/AAAA and C batteries. If your household uses only one cell type, a simpler single-chemistry charger may be more straightforward, but for mixed inventories this “one box” approach is the selling point.
USB power input for desk, travel, and car charging
The charger accepts USB input (5V, up to 2A). That makes it easy to run from common USB power sources, like a laptop or a car USB adapter, without needing a wall outlet charger.
Selectable charging current and a percentage capacity display
You can switch charging current using the provided “Q1” button, with modes listed as 0.5A (500mA), 1A (1000mA), and 2A (2000mA). An LCD indicator shows battery charge capacity in steps of 25%, 50%, 75%, and 100%. That’s helpful for “at a glance” readiness, even though it is not as detailed as voltage monitoring.
Safety-focused design elements
It includes built-in protection for short circuit, overheat, and over-voltage, with an auto power-off feature when the battery is fully charged. The exterior is described as fire-prevention PC+ABS material, which is relevant for basic durability and heat resistance in normal use.
Pros and cons in plain language
Best for
- People who want one USB charger to handle both 3.7V lithium-ion cells and 1.2V Ni-MH/Ni-Cd cells
- Desk, travel, and “wherever there’s USB power” use cases
- Buyers who like a simple percent-based readout to judge charge status quickly
Who should avoid it
- Anyone who needs to charge multiple batteries simultaneously, since it’s a single-slot charger
- Shoppers who require precise voltage or advanced diagnostics beyond a percentage indicator
Comparison points to consider vs other chargers
When choosing a charger in this category, compatibility and workflow matter more than marketing claims. Here are the main comparison factors to use:
- Mixed battery support: If you routinely charge different chemistries (lithium-ion plus Ni-MH/Ni-Cd), prioritize chargers that explicitly list both.
- Charging capacity and current modes: Look for selectable current levels if you want the option to balance speed with battery handling preferences.
- Power source: USB input is a big plus for travel, but confirm the charger’s voltage and current requirements align with your USB adapter.
- Charging bay count: If you typically need to charge multiple cells at once, a multi-slot charger may save time.
Bottom line verdict
The Swanlake charger is a practical pick for mixed-battery households and travelers who want a compact, USB-powered way to charge both 3.7V lithium-ion cells (including popular 18650 and 21700 families) and 1.2V Ni-MH/Ni-Cd AA/AAA-type cells. It looks especially appealing if you value the simple percent display and current-mode switching. The tradeoff is the single-slot design, so it’s best when charging one cell at a time fits your routine.
FAQ
Is this charger only for 18650 batteries?
No. It supports a range of 3.7V lithium-ion rechargeable cell sizes (including 18650 and 21700 families) and it also supports 1.2V Ni-MH/Ni-Cd AA/AAA-type batteries and C batteries.
Does it charge from USB?
Yes. The charger is designed for USB input (5V, up to 2A), which makes it suitable for a laptop, computer, or USB car charger.
How does the charger show battery status?
It uses a capacity indicator that displays charge in percentage steps: 25%, 50%, 75%, and 100%.
Can I choose a slower or faster charging current?
Yes. It offers selectable current modes listed as 0.5A, 1A, and 2A, switched via the “Q1” button.
Will it stop charging when the battery is full?
Yes. It includes auto power-off when the battery is fully charged.
Is it fast enough for everyday use?
Charging speed depends on the selected current mode and the battery’s starting charge level, but buyers describe the experience as fast for supported cells. If you prioritize speed, use the higher current mode.
How many batteries can it charge at once?
It’s a single-slot charger, so you’ll charge one battery at a time.
Specifications
| Product Title | 18650 Battery Charger AA AAA Fast Charger for 3.7V Lithium ion 18650 18500 14500 21700 17500 16340 26650 20700 and 1.2V LiFePO4 Ni-MH/Ni-Cd AA AAA C Batteries(no Batterie) |
|---|---|
| Category | Electronics > Household Batteries, Chargers & Accessories > Battery Chargers |
| Brand | Swanlake |
| Manufacturer | alinalove |
| Color | 1-slot |
| Product Dimensions | 1.25"D x 2"W x 4.84"H |
| Output Voltage | 3.7 Volts |
| Input Voltage | 5 Volts |
| Current Rating | 2 Amps |
| Amperage | 2 Amps |
| Compatible Devices | 18650, 18500, 14500, 21700, 17500, 16340, 26650, 20700, 1.2V LiFePO4 Ni-MH/Ni-Cd AA AAA C batteries |
| Connector Type Used on Cable | USB |
| Number of Ports | 2 |
| Item Dimensions D x W x H | 1.25"D x 2"W x 4.84"H |
| Mfr Part Number | Jiazhounengybty40-1 |
| Specification Met | RoHS, UL |
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