Amazing machine.
This isn’t your average discount store charger. This particular model has selectable charging, test and refresh modes, where one can also select the current in milliamp-hours (mAh). These can be selected on a per-slot basis, or across all four slots. Discharge runs to 0.9v on NiMH-type cells, and 3.0v on LiIon-type cells. Charge runs to 1.5v on NiMH-type cells, and 4.2v on LiIon-type cells. The charger will auto detect the cell type when the battery is inserted into the spring clip. Those clips handily accommodate a range of sizes.
I’ve been using the NiMH-range “Discharge Refresh” (DR) mode for a couple solid days now, attempting to restore a 4-pack of (potentially-sacrificial) AAA cells. These were Panasonic-branded, with a 750 mAh advertised rating. Initial DR cycle yielded an actual capacity of ~20 mAh (yikes!). Repeating the DR cycle at increasing mA ranges (200-700 mAh) over the span of a couple days eventually restored two batteries to a 600 mAh capacity, and two to 700 mAh capacity (!). Running them down in a test flashlight and measuring the time to discharge seems to verify the charger’s measurements.
I was also able to resuscitate some ~8-year-old 18650 cells from a laptop battery I had lying around. They aren't storing anything like their rated current (rated 2600 mAh, tested 1000 mAh with this charger), but are good enough to repurpose in DIY battery housings.
I only really see two “cons” with this unit. First, the user interface is a bit clunky. It doesn’t always respond on the first button push. And, while it does a good job indicating which slot is selected, it’s not really apparent what options can be changed at a given time. Some options seem locked out while a cycle is in progress.
The second issue is the single folded-page instruction sheet. While it makes a valiant effort for what it is, it does assume a degree of familiarity with battery chargers. Coupled with the clunky interface, this could be bad news for non-technical sorts (or technical sorts who aren’t familiar with battery technology).
I would also note that charging and discharging can take a long time. My AAA cells took days to complete this refresh, for example, and they’re relatively small cells. I expect it will only take longer as the capacity goes up. Even the instruction sheet warns DR can take “tens of hours.” Having said this, I personally consider this a “pro” more than a “con”... one will get better service life out of a trickle-charged battery than a fast-charged one. However, if you do need that fast charging capability, it may be better to look at a different model.
Obviously none of these is a show-stopper for me. If one likes pressing buttons, and can be patient while it works, this is a fantastic value. I intend to get another and migrate back to regular use of my rechargeable cells. Amazing machine.
Verified purchase: YesCondition: New