Opus BT-C3100 Charger/Battery Tester


$ 39.99
28 reviews

SKU: opusbtc3100

This product is eligible for further discounts depending on how many you buy! You can purchase other products in the same category (batteries, chargers, or accessories) and it will add to the wholesale discount. Add some products to your cart to test!

This is the Opus BT-C3100 v2.2.  This is identical to the BT-C3400 that some other vendors are selling.  This is the most full featured charger we sell.  It can do all kinds of stuff in addition to just charging batteries, including testing and cycling them.  

This product is for advanced users only. We will not provide advice or technical support in using it to test your batteries.

Opus BT-C3100 Features:

  • 4 independent channels.  Most chargers have some channels connected together but not this one.  You can have each channel doing a different thing, one could be analyzing while another is charging, they could all be charging at different rates, the sky is the limit.
  • Internal resistance quick battery test mode checks internal resistance of batteries
  • Discharge testing up to 1A checks that your batteries really have as many mAh as they say they do.
  • Charging up to 2A per channel (up to 2 batteries) or 1A per channel (up to 4 batteries) allows very fast battery charging.
  • Refresh mode allows you to cycle batteries automatically
  • Charges Li-ion, NiMH, and NiCd
    • NiMH/NiCd sizes:  AAAA, AAA, AA, A, C, and SubC
    • Li-Ion Sizes:  10440, 14500, 14650, RCR123A (17340), 17500, 17670, 18350, 18500, 18650, 19670 (protected 18650), 25500, 26500, 26650, 20700 (including IJoy)
  • Can be set to 3.7V LiFeO4 charging or 4.35V high voltage li-ion charging by a switch on the PCB.  Default li-ion charging mode is 4.2V CC/CV.
  • Minus delta voltage charging for NiCd/NiMH reliable charging.
  • New backlit LED display tells you information

In the Box:

Customer Reviews
4.9 Based on 28 Reviews
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Brad H.
United States United States
  • What device/application do you use this with? Samsung 25R, 20Q, LG ABB4 making packs
Durability Problems - 12 chargers, 800 cells

Bought a dozen chargers to capacity test and process 18650's. I've had a lot of failures of the devices in the 3 weeks I've been running them despite running them gently. Protocol has been 300ma charge and discharge test for all cells with lots of ventilation in the coldest room of the house, clean air, no dust or pet dander. Instead of a dozen wall warts, I used loose barrel plugs and run everything off of a trustworthy 12v30a power supply and voided the warranty. -2 charges have had fan failures. I knew the fan was a problem from some forum posts so I wasn't surprised. Cheap bearings. -1 charger has a bay that will not switch out of Charge mode. I can't select any other option. I assume some bit of circuitry is fried. The remaining bays work fine. -1 charger has a bay that stops charging at 3.6v while still dumping the amps into the cell, resulting in the cell non-catastrophically failing. They got hot but never vented or burned. Killed 3 cells in a row that way. The remaining bays work fine. -1 charger consistently reads high capacity on discharge. Research said that some had miscalibrated bays but one entire device is off by 5-10% high So I'd guess you've got a three-in-five chance of getting a charger that will function flawlessly after 3 weeks of use. Another has a fan on it's way out. I'm down from processing 48 cells at a time to 38 cells at a time as of time of writing. Everything with Liion Wholesale went fine.

william k.
United States United States
  • What device/application do you use this with? Flashlights , metal detectors, RC cars
great charger

Nice charger. The refresh mode helped bring alive some Ni-Mh batteries I had laying around. After being abused for years in the wall wart chargers, it was nice to get real information on battery health. It is also nice to put Li-Po batteries in storage mode.

Canada Canada
  • What device/application do you use this with? EV battery packs
Bang for your buck

This charger has so far impressed me. From the day I received it it has not stopped day and night processing batteries for about one month so far. My only regret is not buying two of them, because doing four batteries at a time when you have 100+ to get through is long. It has revived batteries I thought were dead by using the Discharge refresh mode. Has useful features and you can do 4 batteries independently in different modes. Fan is not bothersome if you have it in a closed door room.

Piotr D.
United States United States
Great prices, fast shipping, just as described

Product was shipped fast and arrived just as described.

derek s.
United States United States
  • What device/application do you use this with? Flashlights, bike lights and weapon lights.
Good value for the money

Nice, full featured charger that's pretty hard to beat for 30 bucks. The fan on mine is intermittently noisy but it doesn't really bother me because getting a nicer charger will probably cost substantially more money.

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