XTAR VX4 Visible Mixer 1.5V/3.6V/3.7V Li-Ion 3.2V LiFePO4 1.2V Ni-MH Batteries Charger and Battery Capacity Tester

This is a great charger and capacity tester for Lithium (Li-Ion & LiFePO4) and NiMh batteries; it does not do alkaline, Ni-Cad, or other types of rechargeable batteries. It comes with a nice well made pouch, USB-C charge cable & AC adapter (must use included adapter for full battery charge power & functionality to the unit), and instructions. The lettering in the instructions was super small, so I had to scan it, then print it in a magnified format (see attached in English for your convenience). First, some terminology for consistency: • mWh stands for milliwatt-hours and represents the total energy a battery can store and deliver. • mAh stands for milliampere-hour and represents the battery's capacity, indicating how much electrical charge a battery can hold. I've used this unit to test several brands of rechargeable AA Li-Ion batteries (see links below for my reviews). None, not one, reached their advertised mWh capacities. In their reviews, many claimed that the batteries were "great" and lasted longer than their NiMh and Alkaline batteries, which is to be expected, however, "great" doesn't mean they lived up to their advertised capacities. This unit will definitively tell you. Lithium batteries discharge at a consistent 1.5V from beginning to end, even when the charge is very low and near 100% depletion, so a regular instant battery tester doesn't work as it will show a lithium battery as being consistently and fully charged until there was about 0% charge left (eg. a 10% charged battery would still show as 100% fully charged). However, 100% charged doesn't mean the battery is charged to it's max capacity, only that the battery has reached the limit of its storage capacity. Think of it this way: an old rechargeable battery that has a diminished capacity, will only charge up to that level, and still show 100%. This unit can do two functions: 1) charge-only, 2) determine battery charge levels (mAh and the mWh). ***You cannot just put batteries into the unit for an instant charge level test due to the above*** To just charge the batteries, plug the unit in to the wall, select the "charge" function, then put the batteries into the unit. Although it will self-detect the type of battery you put in, you can manually select it as well (it will override your selection if the battery type is different). To determine the battery's charge capacity, the unit will first fully charging the battery(s), then fully discharging them (the battery capacity levels are determined here), then fully charging them again so you can use them (C-D-C). During the discharge phase, it will continuously calculate the charge level as it depletes. When the full CDC cycle completes, the unit will display "Done" with both mAh & mWh for lithium batteries, and just mAh for NiMh batteries. Understandably, this process can take several hours depending on the actual charge capacity of the batteries; the higher the capacity, the longer it will take. The nice thing is that you can charge any number of batteries, up to 4 total, and each battery can be a different size and type (eg. AAA NiMh with AA Li-Ion and AA LiFePO4). Size is a bit larger than I expected (6.77"L x 5.11"W x 1.63"H), but with the robust displays for each battery and number of batteries it can simultaneously handle, it makes sense. Below are reviews to the Li-Ion rechargeable batteries that I've tested, none that charge close to their advertised capacities: My XTAR Lithium (Li-Ion) AA Battery Review: https://www.amazon.com/gp/customer-reviews/RSUM0LDFT2FPX My SincehHoly Lithium (Li-Ion) AA Battery Review: https://www.amazon.com/gp/customer-reviews/R390K7RXXBV8VN My Delgeo Lithium (Li-Ion) AA Battery Review: https://www.amazon.com/gp/customer-reviews/R2OPXD8DHSCY37 My RayHom Lithium (Li-Ion) AA Battery Review: https://www.amazon.com/gp/customer-reviews/R2Z9KF179P01ZH

I almost passed on this after reading a review saying it charged at a much slower rate. That person didn't take the time to look what was going on, it does. The charger takes between 9 and 10 minutes to analyze the battery at 150mA charge rate, then kicks up to full charge rate. It is only AA batteries that it does this with. Likely a safety feature looking for problematic batteries I would imagine. I mainly bought this for mobile charging when I'm away from home and I only want to carry one charger. Working great on AA batteries and 18650 Li-ion batteries as well.

Device is great, simple, solid display ,working as intended for various batteries, with fast charging . The price is good for value. Be aware device is bigger then appear on pictures

This charger works great for 1.5 Li ion AAA and AA size batteries and it works great for NiMh also it’s easy to use it works with other brands besides Xtar it is very useful for grading the capacity of your batteries

If your main purpose is to test 1.5v lithium (AA/AAA) - this is the tool. Pros: Test 1.5 volt lithium – unique feature as most do not offer this and at a low price – yet. Opus is NOT 1.5 volt charge but can discharge at CC ((I do not have any Opus items). Cons: limited functions – no ohms, length of discharge, or discharge only Other reviews (Levi Thomas – not affiliated) I would agree with so no need for me to add such detail. While I do have several testers it is far less than 100 so… I also compared this with my Atorch (.2 - .3 mA CC with v cutoff at 1.1v) and results are similar for mAh output. I have been working this device out testing multiple batteries to get accurate capacity (mAh) – just a reminder mWh = mAh * V so even with 1.5v lithium being advertised mainly with mWh you can still use the calculation to what you are looking for. It seems that the context of battery ratings differ (at least between me and the mfg). If you offer a 1300 mWh batteyr then the mAh rating should be around 867. Often, in my experience, it is much lower than above; so this can help me ID the ones that are properly represented where before it was just an Atorch or similar single testing options Already tested several brands so you can see them. Complaints- Final thoughts: Biggest to me is discharge testing. It will fully charge then discharge (then charge again) for the test cycle. XSTAR is big enough they should have added more options: • Just a discharge option – no charge cycle first – why? So you can test capacity loss over inactive time - shelf life • Resistance test – list ohms • Set discharge rate (or list what it is – you can set charge mode but unsure it is the same) - rate is 250-300mohm • Set cutoff voltage • Duration of discharge • Add 9 volt option