Test/review of Keeppower 18650 3400mAh P1834J (Black) 2019

Keeppower 18650 3400mAh P1834J (Black) 2019

Official specifications:

  • Nominal capacity: 3400mAh

  • Minimum capacity: 3250mAh

  • Nominal voltage: 3.70V

  • Charge voltage: 4.20 +/-0.05V

  • Discharge cut-off voltage: 2.50V

  • Standard charge current: 1500mA

This is protected high capacity 18650 cells from Keeppower.

The two cells tracks nicely and the protection trips when they are overloaded.


This is good protected cells. They can deliver above 8A for a short time and a bit below 7A during a full discharge.

Notes and links

The batteries was supplied by Keeppower for review.

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries
Graphical comparison to 18650 and other batteries
Table with all tested LiIon batteries

Thanks HKJ!

Thanks HkJ, great review and test.

Is this probably good high capacity cell definitely for longer runtime usage and for electronics device that consume less power.

Cell has protection board which good for some electronics device aren’t equip with safety discharge limit.

Overstated capacity and energy claims as usual. Even if a little bit.

As (this) technology is the battery does not “go up”, it exclusively “goes down”. This means you never ever see rated figures. Lousy imho.


To be fair, this battery’s capacity is rated at a discharge to 2.5V. HKJ only discharges it to 2.8V, which might not consume full capacity of the cell.

Once you get down below 3.0v the drop is precipitous. Not really much down there that’s useful, and it’s not good for the battery. Who is actually going to use a cell like this from 4.2v > 2.5v at 0.1A on a routine basis? It would be like testing MPG on a car by driving it at 30mph a glass track with a tailwind and crowing about the results.
You can nitpick methodology, but it’s mostly just marketing hype, and they seem to over ride the engineering dept anymore. Seems very few are immune to it.

If you need to know how much capacity until 2.5V you need to look somewhere else, at ECF for example (Mooch's reviews). Barely anything changes, though.

This cell claims 3250mAh minimum capacity, a figure which is not met at less than rated discharge (0.2C = 680mA) down to 2.8V (3236mAh at 0.5A). Suffice to say KeepPower does not seem to do any in-house testing to their rewrapped cells, their cell testing machinery is incorrectly calibrated, they overlook the results or any combination of the aforementioned.

3400mAh? Not by a long shot…


Based on the 1A, 3A, and 5A discharge curves, the cell under the wrap appears to be a LG MJ1.

HKJ, I do not see this battery listed in your Battery Table.

SubLGT, the LG MJ1 review is here.

The table generator has some automatic quality check of the data and will only include batteries if they fulfil them. The problem may be that I only have a 0.2A discharge for one of the batteries.

I could have been more clear. I meant that the P1834J battery was not in HKJ’s Battery Table.