Review on 🔋 Opus BT - C3100 V2.2 Intelligent Digital 4 Slots LCD Battery Charger | Li-ion NiCd NiMh Batteries Compatible | US Plug | Purplish Blue by Shannon Cool

A few years ago I bought AA and AAA Duracell and Rayovac Nickel Metal Hydride (NiMH) rechargeable batteries and a Duracell 2 cell fast charger. A few months later several batteries were showing up as 'defective' and it annoyed me that I had a bunch of batteries less than a year old that had failed. I spontaneously decided to buy this charger based on a few YouTube videos. and the charger's ability to test and charge cells individually. I figured it would also be a great way to test individual cells in failed cordless power tool battery packs so I can replace the failed cells and revive the battery packs (which I have yet to do). loaded the batteries into this charger from the Duracell charger and was amazed that the Duracell charger only charged the batteries to 1.08 volts! These batteries should be fully charged at around 1.5 volts and should be charged when they drop to 900 mV (0.9 volts). No wonder I could only use these batteries intermittently for about 20 minutes! So I took supposedly defective batteries and found that they were about 0.8 volts below the recommended minimum voltage. After some time in this charger I had 4 fully charged batteries. I decided to run them in this charger's test mode and found that they all have or exceed the rated capacity listed on them. Numerous test runs confirmed the results, so I was relieved to see that my batteries were not defective, the problem was the Duracell charger! In the months since purchase and dozens of charge cycles, all my batteries are still tested perfectly and without damage. capacity reduction. I was even able to bring a few dead AAA NiCds back to life from dollar store solar lights, although I would NOT recommend this charger for this purpose as the charge current is too high for repeated use on small cells. The charger is capable of charging 18650 cells, although I haven't used it for that (yet). The internal fan, which dissipates heat during the battery test, is silent - you have to hold the charger right up to your ear to hear it. The interface is a little clunky at first, but once you get used to it, it's not too bad. The ability to change the reading to show charging voltage and current is a nice feature. When the batteries are fully charged, the device automatically switches to a very low "trickle charge" to safely keep the batteries at 100% when needed, so there's nothing wrong with leaving the batteries on the charger indefinitely. a permanent spot on my desk, literally a foot from my computer. It definitely deserved that spot, and what I paid for the charger was cheaper than replacing all the batteries that my Duracell charger incorrectly claimed were defective - and those new batteries would end up in the same undercharged state, and incorrectly as be marked defective. In that respect, this charger has essentially paid for itself.