Battery charger LI-ION, NI-MH XTAR VC4

Xtar is a renowned manufacturer of high-quality chargers for Li-ion batteries, flashlights, and rechargeable Li-ion batteries. Xtar products are sold in over 120 countries, including the USA, Germany, Japan, and Russia. Xtar uses the highest quality materials to manufacture its chargers, from the plastic housing to the efficient electronics. All Xtar chargers are CE certified, required in European markets.

The VC4 is a professional processor-based charger with a three-stage TC/CC/CV charging process and an LCD display. It charges 1-4 3.6/3.7V Li-ion and Ni-MH cells of any capacity in sizes AAA/R03, AA/R6, 10440, 14500, 14650, 16340, 17500, 17670, 18350, 18500, 18650, and 18700. The two outer channels can charge batteries in sizes R14, R20, 20700, 21700 (unprotected only), 22650, 25500, 26650, and 32650.

The Xtar VC4 charger's backlit LCD display provides real-time information on the charger's operating status: voltage of the batteries being charged, charging current, charge used to charge the cells, indicates any errors, and indicates charging completion. The current operating status for both channels is also displayed. Switching between the other two channels is possible using the CH button on the charger housing. Information about the charge used can be used to measure battery capacity. To measure the battery capacity, discharge the battery to its appropriate cut-off voltage (usually 2.5V for Li-ion, 0.9V for Ni-MH) and insert it into the VC4 charger. After charging is complete, the display shows the charge used to charge the battery. This value will always be 3-5% higher than the actual battery capacity. This is because the battery charging process is never 100% efficient, meaning a slightly higher charge than the actual cell capacity is required to charge the battery.

The maximum charging current is 1A and is only available for the two outer channels and only when the middle channels are not in use. Batteries in the middle channels are always charged at 0.5A. When charging 3 or 4 batteries, the VC4 charges all batteries at 0.5A.

What is the TC/CC/CV charging method? It is a three-stage charging process for Li-ion cells that ensures the cell is maintained in good condition by charging with the appropriate current at each stage and terminating the charging process at the appropriate time.

The individual stages of the TC/CC/CV process are:

• TC phase: Cells discharged below 2.9V are "waked up" with a lower current.
• CC phase: After reaching 2.9V, the cell is charged with a constant current of 0.1A to 1A (depending on the power source used and the number of batteries being charged).
• CV phase: When the cell is almost fully charged, the charger switches to charging with a decreasing current until the cell voltage reaches 4.2V. Once 4.2V is reached, the charging process is complete - the battery is fully charged.

Charged batteries left in the charger will naturally self-discharge. Li-ion battery charging will resume when the battery voltage drops below 3.9V. For Ni-MH batteries, charging does not resume when the voltage drops due to self-discharge.

The Xtar VC4 charger has a function for reactivating deeply discharged cells and cells with a voltage of 0V. Many chargers on the market are unable to charge such batteries. This is where the Xtar VC4 charger comes in handy, allowing such cells to be "recovered" in many cases. Simply insert the deeply discharged battery into the VC4 charger as you would during normal charging - the charger will detect the discharged cell and attempt to reactivate it. Note! Cells discharged below a certain level are irreversibly damaged and may not be reactivated. Avoid deep discharge of Li-ion and Ni-MH batteries - this can significantly reduce their lifespan and capacity, or even lead to complete failure.

The Xtar VC4 charger comes with a USB cable. A power supply is not included. Any charger with a USB cable, such as a phone charger, a USB port, or a computer with a free USB port, will power the charger. The recommended USB power supply is 2.1A (2100mA). A lower-power supply can be used; the VC4 will adjust the charging current to the power source's capabilities.