Speedy 18650 Battery Charger XTAR PB2C USB Output Function, Portable Li-ion 18650 Battery Charger Box w/USB Port and LED Display for all 18650 Batteries（Batteries NOT included)

Paired with DTK 3000mAh 18650 batteries, this thing rocks. It charges them fast and to 4.2v every time. Even without the power bank feature it is worth the money just as a charger.It has a simple design, but is very premium. The shell of the device is plastic but it has a really soft, smooth matte texture. The 3 digit display is bright and easy to read.Power bank feature- I used the ampere app to test charging current into my phone. It read about 1600mA on average. What must be considered though is that the app takes the actual current going into the batteries, and subtracts what the phone is using from that amount, to give the actual amount the batteries are getting. Disconnected the cable, and ampere said my phone was drawing 450mA from the battery. 1600+450=2050. 2.05 amps. So the 2 amp charging current capability is not a lie, however it must be stated that not every device will get 2 amps, because current is a lot easier to control/limit than voltage. The device will only take how much current it wants. If this thing could privide 1 million amps and a 2 amp rated device was connected, it would take 2 amps. The one minor caveat is the current cutoff of 120mA. I have a tiny rechargeable oscilloscope that only takes a few mA initially and climbs up to about an amp via the smart charging IC. It does not climb fast enough to beat the power bank circuit's cutoff timer. That really isn't an issue with the power bank and if you had the power bank going into a USB hub with an abnormally high standby current, you'd want the power bank to shut off to save power.TL;DR- excellent 18650 charger with a premium feel that includes a useful high current USB output for use as a power bank, which is my main use for it.

I like being able to use my own batteries for a power bank. When I get home from a trip I like to make sure they're charged/discharged to about 50% to prolong their life. With a sealed pack, I never really knew for sure. And if I needed to get that down to 50%, the only way would be to discharge them by charging my phone, which was a pain sometimes.This solves that problem, and also gives me the ability to use larger capacity cells - 2x3500mAh. So 7000mAh is enough for me on most backpacking trips. Being able to charge them in the pack is nice too. The display with actual % remaining is nice to have instead of a few lights like most have. It can be hard to read in certain light, but that is common with those types of bright displays (mini voltmeters, etc).The cells are in there tight and hard to get out since there's really nothing to grab on to. I can pick the top with my nail, but could use anything flat/rigid if it's ever a problem. On my first charge the cells ended at 4.21v. Slightly high, but nothing to worry about. I'll keep an eye on this going forward to see if that varies at all.This is just about perfect like all the other Xtar chargers I have.

The media could not be loaded. I absolutely love the purpose of use for this device. I can put my 18650 flashlight batteries in there, charge them for use in my flashlight or use the whole thing as a charger for my phone. I love the versatility! After a few uses, however, it just stopped working. I can charge it just fine, but it won't charge other devices.I understand this is one of the first models in this line, but looking at the reviews for the newer models shows that they are often faulty as well, so getting a new version doesn't seem to fix things. I would be happy for Xtar to contact me about this. In the video attached to this review, you can see how loose and wobbly the USB Jack is. I think it's because of this that it won't charge my phone anymore.

Pros:- It can take 3400mAh Panasonic batteries, resulting in a true charge of 6800mAh at 3.6V, or about 4900mAh over the USB output port. This means, if your cell phone has a 3200mAh battery, you can charge it 1,5x.- This unit is very portable.- The battery door lid is magnetic. Very nice!- The battery percentage indicators can function as a small blue LED light at night.- The battery percentage indicator, indicates in single increments (1-100% in steps of 1%).- With batteries, this unit costs about the same as other battery packs with non-removable batteriesCons:- This unit only has 1 output USB port. Be aware!- This unit does not have a dedicated LED flashlight.- It also puts out 2.1A on the output USB port, which might damage some cellphones, or makes them rapid charge.- The unit only takes flat top batteries. If you use round top batteries, they will get stuck. They should have mentioned it in the description!- The LEDS give overall percentage of charge. If the readout reads '50', it's unclear if this means 50% in the first battery, and 50% in the second, or 100% in the first with 0% in the second. In other words, this unit does not display individual battery charge.- The unit itself uses little battery on standby. I seem to lose about 1 percent per day of battery, without using it.I use Japanese 3400mAh Panasonic cells, which are known to be the best, so I assume I either have a broken cell, or this unit has parasitic losses.- Higher than 2.4A chargers are not supported. USB 3 chargers may potentially damage the device.Other facts:- Charging happens via USB type B. A bit outdated, but a good use for all those old charging and data cables!- Slow charging can happen with a 1000mAh charger. Fast charging can happen with a 2100-2400mAh charger.- Total charge time ~3,5 hours for 2x 3500mAh batteries (less with smaller batteries).Hints:- If you want your device to last, go with Japanese branded, flat top cells from Panasonic, like these:https://www.amazon.com/Panasonic-NCR18650B-Rechargeable-Battery-Transport/dp/B01C4GFVN8/You may find cheaper, often overrated Chinese batteries, that will last less long.- Slow charging your batteries, increases battery lifetime.- Never fully discharge Lithium batteries. It damages them internally.- If you don't plan on using the batteries, it is best to store them at a ~80% charge, in a dark, dry place of about 75F (inside a cabinet). Storing them in a wet, cold or hot environment, can decrease battery lifetime.- If the batteries get warmer than body temperature while charging, you may want to decrease charging current (stop fast charging; start slow charging).- If your batteries feel hot to the touch, disconnect, and place in a fire-safe zone. Batteries should never exceed 104F/40C when charging!- Never short-circuit batteries!