LG MJ1 18650 (3500mAh)
(6 reviews)
3500mAh in an 18650 format: the LG MJ1 pushes capacity to the top of what this format allows, for uses where runtime matters more than current.
Characteristics
- Format: 18650 (INR18650-MJ1)
- Capacity: 3500 mAh
- Continuous discharge: 10A maximum
- Nominal voltage: 3.6V (lithium-ion)
- 3500mAh, one of the highest capacities in 18650
Detailed overview: LG INR18650-MJ1 3500mAh lithium battery
The LG MJ1 (full reference INR18650-MJ1) is a cylindrical lithium-ion cell in the 18650 format (0.7 in / 18mm diameter, 2.6 in / 65mm long) that made its mark by pushing this format's capacity towards its upper limits: 3500mAh, a figure that remains among the highest ever sold in a bare 18650. The cell's own wrap lists a guaranteed minimum capacity of 3400mAh, with 3500mAh being the typical capacity measured in lab conditions.
This high capacity comes at the cost of a more modest continuous discharge current than power-oriented cells: 10A maximum, against 15A or more for a cell like the Samsung 30Q. The MJ1 is therefore not the first pick for a very high-power electronic mod, but it excels wherever runtime is the priority: long-runtime flashlights, DIY battery packs built by hobbyists, light e-bikes, home-built power banks and portable tools with modest peak current needs.
Its nominal voltage is 3.6 to 3.7V, with a maximum charge voltage of 4.2V, like almost all lithium-ion 18650 cells. It is supplied in an unprotected Flat Top version (flat positive terminal), with no built-in protection circuit, for maximum compatibility with existing cell holders and devices, weighing about 1.7 oz (49g).
Two precautions apply. First, being a bare unprotected cell, it is intended for experienced users who know how to handle, transport and recharge it safely with a charger suited to 18650 lithium cells. Second, the MJ1's popularity makes it a prime target for counterfeits: it is recommended to buy it from a trusted specialist retailer that verifies the authenticity of its stock, rather than chasing the lowest price found online.
Our tester's review: Pierre Freysinger
The MJ1 joined our bench to rebuild a light e-bike pack, a use case where every extra mAh translates directly into range. Verdict after several charge cycles: the rated 3500mAh is genuinely there, clearly ahead of older 18650 staples like the Panasonic NCR18650B (3400mAh). The trade-off, logically, is a more limited continuous discharge current (10A) than a cell like the Samsung 30Q (15A): the MJ1 is not built for very high instantaneous current, but for maximizing range. On that specific ground, it is a benchmark. One caveat worth flagging: genuine LG cells have become harder to find at some generalist retailers, and counterfeits circulate actively under this exact name precisely because it is sought after. We would strongly recommend a specialist retailer that batch-tests its stock. For a pack or flashlight where runtime beats everything else, the MJ1 remains an expert's choice.
Frequently asked questions: LG INR18650-MJ1 3500mAh lithium battery
Yes. LG Chem's battery business was transferred to its subsidiary LG Energy Solution in 2020, but cylindrical cells like the MJ1 continue to be manufactured and sold under the LG name at specialist retailers, exactly as before.
Both are capacity-focused benchmarks of the 18650 format. The MJ1 (3500mAh) slightly edges out the NCR18650B (3400mAh), at the cost of a somewhat lower continuous discharge current, while the Panasonic is a more all-round pick.
It suits mods that stay within its 10A continuous discharge rating. For uses that push much higher instantaneous current, a power-oriented cell like the Samsung 30Q is a better fit.
This model, highly sought after for its capacity, is widely counterfeited online. It is best bought from a specialist retailer that verifies the authenticity of its stock rather than at the lowest price found on a generic marketplace.
Other products in the "18650 batteries" category
Astrolux E1825 18650 (2500mAh)
$17.68 (3)
Two high-drain 18650 cells: the Astrolux E1825 deliver 2500 mAh and up to 18 A, ideal for powerful flashlights and vaping.
Efest IMR18650V1 3500mAh
$9.99 (8)
A high-drain 18650 cell from Efest: 3500mAh, 10A continuous and the reliability of a brand trusted by flashlight and vaping enthusiasts alike.
Fenix ARB-L18-3400
$21.95 (6)
A straightforward 3400mAh 18650 battery from a trusted flashlight brand: button-top design, built-in short circuit protection, and 500 rated charge cycles.
Fenix ARB-L18-3500U
$24.95 (12)
A premium 18650 battery that recharges through a built-in USB port, no external charger needed: 3500mAh, an LED indicator and multiple layers of protection.
Published on 05/09/2026