WF-138A Dual Voltage 900mA 16340 CR123A Li-ion Battery Charger

Specifications:

• Design for 16340, CR123A Battery
• Cost effective, high efficiency and reliability
• Constant current and voltage
• Built in over voltage, over current and short circuit protection
• Input: 100-240V 50/60Hz
• Output: 3.6V-250mA

Details:

• Design for 16340, CR123A Battery
• This UltraFire charger is a dual channel charger which you can select 3.0V or 3.6V switch before plug-in power supply. It is used for charging CR123A battery

• If your battery is this model, the charger can quickly charge it in your office or on the road. This dual battery charger is an ideal travel charger and also will bring more convenience for you

• At this moment, the charger indicator will show you the charging status clearly. This CR123A charger can charge two batteries at the same time

• And lightweight design makes it very convenience to carry with anywhere which you can put it in your bag

• Of course, you can also charge one battery at a time according to your choice
• Charge your batteries with this UltraFire Charger

How to Charge a Lithium Ion Battery?

Lithium ion batteries are highly efficient and widely used in laptops, cell phones and similar devices. When you charge a lithium ion battery, ions are forced into the anode and cathode of the battery by the electric current. The process of charging is simple, provided you follow some simple precautions to insure safety and to maximize the life of the batteries. Always check the battery manufacturer's specifications before you charge a lithium ion battery. Improper charging may create a serious fire hazard.

• Use a battery charger designed for lithium ion batteries. A charger for lithium batteries should be able to deliver 3.8 to 4.2 volts per cell. Never use a low power (trickle charge) system. This can cause lithium to adhere (plate) to the anode and oxygen to be generated at the cathode, producing an extremely flammable mixture. Lithium ion batteries come with an internal "safety board" that automatically terminates charging when the current rate drops to 10 percent of the initial charge rate, indicating the battery is fully charged. The best chargers also feature a timer you can set to stop the charging process at a preset time.
• Place the lithium ion batteries in the charger and make sure it is plugged in. Depending on how much power remains in the battery it will take two to six hours to fully charge most lithium ion batteries. As an added safety precaution, set the timer to avoid the possibility of overcharging.
• Charge the batteries at the appropriate voltage setting. To maximize the charge, the voltage should be set at 4.20 volts per cell. However, you can extend the useful life of lithium ion batteries by using a slightly lower setting (about 4.10 volts for most lithium ion batteries). This will give you about an 80 percent charge.
• Charge lithium ion batteries to about 40 percent before storing them for long periods. It is not good for the battery to bring it to full charge and then store it, since this will reduce the battery's useful life. To further extend battery life, recharge stored batteries to the 40 percent level every few weeks (check the battery specifications for recommended times).

How Does a Battery Charger Work?

Batteries work because of the electrochemistry between an anode/negative terminal and a cathode/positive terminal. Some battery chemistries have the property of being chargeable, so that when electrical current is fed into them, the electrochemical discharge reaction reverses itself and the battery "recharges."

Only some batteries have the chemistry and construction features that all them to be charged. Also, due to varying battery designs and chemistry, a given battery can only handle a certain voltage or amount of current. For example, the current fed into a lead-acid car battery would be very different from that of a lithium ion mobile phone battery.

• Simple Chargers
• The most common type of charging device is the simple charger. Drawing electric current from a wall outlet, this provides either a constant voltage or constant current and will continue to feed it into the battery until unplugged. Usually a transformer of some kind is involved to convert the voltage. For example, North American wall outlets work on the 110-volt standard, which is inappropriate if directly applied to a 12-volt battery.
• Most charging devices work on this model. They are cheap, but because they never stop feeding in electricity at a set rate and do not stop until unplugged from their power source, they can damage batteries with overcharging if left unattended.
• Trickle Charging
• Trickle charging is a variant of the simple charger in that it puts out a constant flow of electricity but at a very low rate. That rate is set to match the particular battery's decay or self-discharge rate. When the battery is completely recharged, the charging therefore continues only at the rate necessary to keep the battery charged and no more. This prevents overcharging and, therefore, degradation or damage to the battery, but makes the charging process very slow.
• USB Charging
• The USB bus on a computer is standardized with a 5-volt power output. Therefore, many computer accessories are designed to use USB outlets for battery charging. Excepting that it uses electricity drawn from a computer instead of directly from a wall outlet, it is similar to other charging methods.
• Intelligent Charging
• These chargers monitor either the time spent recharging, the temperature of the battery or the battery's voltage to determine when to autonomously terminate charging. This protects batteries from damage or degradation due to overcharging. Intelligent charging is becoming a popular charging feature for devices that use lithium ion batteries, as these are relatively expensive and suffer more degradation from overcharging than some other battery types. 

Lithium Battery Charger Regulations

Lithium batteries are mainly used in electronic devices, with lithium as the battery's anode with a voltage ranging from 1.5 volts to 3.7 volts. A lithium-ion is the most common lithium battery. It is mainly used in portable electronic devices because of its ability to switch lithium from anode to cathode depending on the amount of charge. Regulations are being designed to prevent discharge of the battery and possible explosion, and to give the batteries a longer life.

• Lithium-Ion Battery Charging Basics
• Though it is easy to charge a lithium-ion battery, charging safely is more difficult. The so-called Miracle chargers which help to regenerate and protract batteries do not apply for lithium type. Super-fast charging is also not suitable. Lithium-ion cell manufacturers have strict guidelines for the charge procedures and the pack should be charged as per these rules and typical charge techniques. These lithium batteries have a longer life than regular alkaline batteries.
• Lithium Battery Charger Regulations
• Lithium-ion is a very clean system which does not require grounding like nickel-based batteries. Most cells are nearly charged to 4.20 volts. Charging up to 4.10 volts may reduce the capacity but can provide a longer life. Charging time of most of these chargers is three hours. Batteries in cell phones can be charged up to 1C ( one times the capacity of the pack) whereas those for laptops can be charged at 0.8C or less.
• Overcharging of Lithium Battery
• A lithium-ion battery is designed to operate safely within its normal operating voltage. It becomes unstable if it is charged to higher voltages. Overcharging causes the cell to heat up and if this is neglected, the cell could outlet with flame. One should be cautious to avoid overcharging and discharging. Trickle charging is not applicable for lithium batteries. Overcharging can damage the cell, plating out lithium metal, which is hazardous.
• Regulations of Lithium-Ion batteries vs. Rechargeable Batteries
• Lithium-ion batteries have higher energy density than most other type of rechargeable. They can store more energy, operate at high voltage and has low self discharge rate. But these lithium-ion batteries require sophisticated chargers that can monitor the charging process carefully. And because of their different shapes and sizes each battery requires a charger that suits its size. These chargers are more expensive and difficult to find.
• Safety Regulations
• Every lithium-ion battery pack has safety rules for monitoring charging and discharging of the pack. Commercial packs have protection circuits that limit the charge voltage to 4.30V/cell, 0.10 volts higher than the voltage threshold of the charger. Temperature sensors end the charge if the cell temperature approaches 90°C (194°F). A mechanical pressure switch on some cells permanently interrupts the current path if a safe pressure threshold is exceeded.

Package Included:

• 1 x UltraFire WF-138A 900mA Battery Charger
• 1 x Charging Cable