Skip to content
FREE DELIVERY FOR ORDERS OVER €150 IN FINLAND / ORDERS BEFORE 2 PM WE TRY TO SHIP THE SAME DAY
FREE DELIVERY FOR ORDERS OVER €150 IN FINLAND / ORDERS BEFORE 2 PM WE TRY TO SHIP ON THE DAY

Thorgeon Li-ion rechargeable battery 18650 3400mAh 3.7V – USB-rechargeable, 1 pc

SKU 4751029894120
Sold out
Original price €23.60 - Original price €23.60
Original price
€23.60
€23.60 - €23.60
Current price €23.60

includes VAT 25.5% Shipping costs are calculated at checkout.

Availability:
Out of stock

The Thorgeon Li-ion battery is a rechargeable battery solution with a built-in Micro-USB charging port. You do not need a separate charger — you can charge the battery directly with a standard USB to Micro-USB cable (USB-C/Lightning charger with a suitable cable, power bank, computer, or phone wall charger). A capacity of 3400 mAh and a voltage of 3.7 V make this a versatile option for devices that require a Li-ion battery.

Li-ion battery, 18650 size (18 × 70 mm). 3.7 V voltage. Built-in Micro-USB charging port. Operating temperature −20–50 °C.

ⓘ Coming soon

This product is not yet available. It will be released for sale soon — please check availability again later or ask our customer service.

Technical specifications

  • Product type: Li-ion rechargeable battery (built-in USB charging)
  • Brand: Thorgeon
  • Type: Lithium-ion
  • Capacity: 3400 mAh
  • Nominal voltage: 3.7 V
  • Size standard: 18650 (standard Li-ion size)
  • Diameter: 18 mm
  • Length: 70 mm
  • Height with terminal: 70 mm
  • Weight: 49.8 g
  • Charging port: Micro-USB (built-in)
  • Suitable for fast charger: yes
  • Built-in circuit board: yes (protects against overcharging and overcurrent)
  • Plastic casing: yes
  • Operating temperature: −20–50 °C
  • Number of cells: 1
  • Product code (EAN): 4751029894120
Compatibility and use

Important about size — this is NOT an AAA battery

Although manufacturer data may mention "Micro/AAA" rating, the dimensions indicate this is an 18650-size Li-ion battery — not a traditional AAA alkaline battery. Differences:

  • AAA alkaline battery: diameter 10.5 mm, length 44.5 mm, voltage 1.5 V
  • 18650 Li-ion (this one): diameter 18 mm, length 70 mm, voltage 3.7 V

The voltage of this battery (3.7 V) is more than double that of an AAA. Do not install in an AAA device — it can damage the device. Verify that your device is specifically designed for an 18650-size Li-ion battery.

Typical applications

  • LED flashlights (common size)
  • Electric bicycle auxiliary batteries
  • Device-specific Li-ion batteries
  • Solar-powered lights
  • DIY electronics projects

USB charging

There is a Micro-USB port at the end of the battery for connecting a standard Micro-USB cable. Charge the battery fully before the first use. Charging can take 2–6 hours depending on capacity and power source. The battery contains a circuit board that protects against overcharging — you can leave the charger connected, but for better storage life, disconnect it after a full charge.

Safety

  • Do not short-circuit the terminals — use a casing similar to the original
  • Do not expose to temperatures above 60 °C
  • Take the retired battery to a recycling point — do not dispose of in mixed waste
  • Do not charge a mechanically damaged battery

Delivery

We ship your order from our warehouse in Jyväskylä. Orders placed before 2 PM are usually shipped on the same day. Free delivery within Finland for orders over €150.

Warranty

Products purchased through Lumenled come with a manufacturer's warranty, supported by Lumenled in cooperation with the importer. You can find detailed warranty terms here: Warranty terms of our partners.

Request an offer

Usein kysytyt kysymykset

Is this battery AAA size? The body says so.

No — this is a Li-ion battery with dimensions of 18 mm × 70 mm. The "Micro/AAA" rating found in the manufacturer's information is misleading — the actual size classification is 18650 (standard Li-ion size).

  • AAA alkaline battery: Ø 10.5 × 44.5 mm, voltage 1.5 V
  • 18650 Li-ion (this one): Ø 18 × 70 mm, voltage 3.7 V

The dimensions and voltage differ significantly. Do not install this in an AAA device (remote controls, clocks, toys) — the device may be damaged. Check your device's requirements before installation.

Can the battery be charged with a standard phone charger?

Yes — the battery has a built-in Micro-USB port that works with any USB power source:

  • Phone charger (with a USB-A → Micro-USB cable)
  • Computer USB port
  • Power bank (convenient for travel)
  • Car USB port
  • USB-C charger with a suitable USB-C → Micro-USB cable

A Micro-USB cable is typically NOT included in the package — use your own cable or purchase one separately. Charging takes 2–6 hours with most power sources.

What is an 18650 Li-ion battery used for?

The 18650 Li-ion battery is one of the most common standard Li-ion sizes. Typical applications:

  • LED flashlights — more powerful models usually use an 18650 battery
  • Battery cells for electric bicycles
  • Laptop battery packs (internal)
  • Vaping devices and adjustable cigarettes
  • DIY electronics projects

Always check your device's user manual for the required battery size and voltage (3.7 V Li-ion). Some devices use unprotected battery cells — this battery includes a built-in protection circuit, which increases safety but may make it slightly longer than a "bare cell".

How long is the battery life?

The service life of Li-ion batteries is measured in charge cycles:

  • High-quality Li-ion batteries: 500–1000 charge cycles before a significant drop in capacity (below 80% of the original)
  • Storage matters: it is best to store the battery at about 40–60% charge in a cool place — a battery stored fully charged for an extended period will wear out faster

In practice, a battery lasts 2–5 years in home use. When it no longer holds a charge as long as it used to, it is time to get a new one. Always take a decommissioned Li-ion battery to a recycling point — not into mixed waste for safety reasons.