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The Folomov A4 is a high quality, 4 slot charger that can be used with a very wide range of batteries, ranging from lithium ion to nickel metal hydride (NiMH) and NiCd.
If you want one large go-to charger for your home, this is the one you want.
The Folomov A4 packaging
Supported battery types:
Lithium ion (3.2-3.7v): 10440, 14500, 163400/CR123, 18350, 17500, 18500, 17670, 18650, 26500, 26650, 32650
NiMH (1.2v): D, C, AA, AAA
The Folomov A4 defaults to 250mA, but has a manual selection range that includes 250mA, 500mA, 1000mA, and 2000mA when using up to four cells.
If you want faster charging, the first and fourth slots can handle up to 3000mA if you limit the charger to two batteries. Keep in mind though that faster charging rates are harder on batteries. A good rule of thumb is not to exceed 0.8C, or in the case of a 3500mAh battery around 2.8A. For most people, the 1A charging rate is the best balance for speed of charging and preservation of the battery.
There are four buttons, one above each battery slot. Double click the button to switch between settings and display mode. In settings mode you single tap to rotate between the charging rates, or press-and-hold to change the battery type if it was not autodetected correctly.
I like that this model has fully manual controls on the slots, though the double-click interface is a bit picky on the timing. I also find the “null” text to be a bit funny for an empty slot.
What we like about the Folomov A4:
- Relatively inexpensive and a quality charger
- Supports a massive amount of battery types
- 8A total charge capacity or 3A x 2 fast charging is hard to find among the competition
- Highly rated by HKJ reviews for quality of charging
- Display screen showing battery percentage, charging rate, and voltage is clear and easy to understand
- Reverse polarity protection
What could be improved:
- This charger is quite large, and has a power brick to go with it. This is definitely one that will sit at home due to its bulk.
- The user interface that requires double clicking the button is a bit picky
- No discharge testing or similar, but at the price point that’s not really expected
- Sliders on the slots are a bit difficult to move, but this is a brand new device and I suspect these will smooth out over time.
If you want a straightforward, powerful, and versatile charger, the Folomov A4 is a great option for the money. While there is no fancy auto-detection for charge rates, battery testing, or power bank usage, that’s not what this model is meant to be. There is much competition in this space with products from Nitecore (i4, sc4), Miboxer (C4), Zanflare (C4), and more. However, they all seem to be lacking a combination of fast charging rates and reliability.